PROGRAMME ABSTRACTS - LU · FP7-REGPOT-CT-2011-285912 Conference organizers Scientific Committee Prof. Janis Spigulis, Latvia – Chair Dr. Janis Alnis, Latvia Dr. Aigars Ekers, Latvia

1st International Conference “Biophotonics – Riga 2013”

29–31 August, 2013

Research Training Course “Biophotonics – Riga 2013”

26–28 August, 2013

Exhibition “Biophotonic Technologies – Baltics 2013”

29–31 August, 2013

PROGRAMME

ABSTRACTS

Riga, Latvia2013

Supported by FP7 projectUnlocking and Boosting Research Potential for Photonics in Latvia – Towards Effective Integration in the European Research Area (FOTONIKA-LV)FP7-REGPOT-CT-2011-285912

Conference organizers

Scientific CommitteeProf. Janis Spigulis, Latvia – ChairDr. Janis Alnis, LatviaDr. Aigars Ekers, LatviaDr. Ricardas Rotomskis, LithuaniaProf. Alexander Priezzhev, RussiaProf. Goran Salerud, SwedenProf. Katarina Svanberg, SwedenDr. Arnolds Ubelis, LatviaDr. Roman Viter, Ukraine

Local Organising CommitteeDr. Ilona Kuzmina – Co-ChairProf. Janis Spigulis – Co-ChairDr. Ojars BalcersMSc. Dina BerzinaMSc. Dainis JakovelsMSc. Natalija LesinaDr. Uldis RubinsMSc. Inga ShiranteMSc. Inga Saknite

© University of Latvia, 2013

ISBN 978-9984-45-759-8

3

PROGRAMME

Training Course (Auditorium #13, Raina Blvd. 19)

Monday 26 August

08.30 Registration08.55 Opening of the Training course

Biophotonic Environmental Sensors

09.00 M. Mak (SE). Photometric Nanolabels for Biosensors and Bioassays 09.45 N. Starodub (UA). Actual Problems in Environmental Monitoring,

Diagnostics and Agriculture: Role of Biosensors in Solving Modern Practice Tasks

10.30 Coffee break

11.00 C. Nacke (EE). Industrial Approaches in Biosensors

12.00 Lunch break

13.30 M. Bechelany (FR). Integration of Metal Oxide Nanotechnology for Sensor/Biosensor Applications

14.15 R. Viter (UA). Introduction of IRSES/Metal Oxide Nanostructures for Sensors and Biosensors

15.00 Coffee break

15.30 S. Balme (FR). Confocal Microscopy for Biosensor Applications16.15 V. Khranovskyy (SE). Photoluminescence Spectroscopy of Photonic

Semiconductor Materials as Optical Transducers for Biosensors

Tuesday 27 August

Biophotonic Medical Sensors

09.00 S. Andersson-Engels (SE). Fluorescence Diagnostics in Medicine10.00 G. Salerud (SE). Multispectral Diffuse Reflectance Imaging of Superficial Tissue

Methodology and Implementation

11.00 Coffee break

11.30 A. Priezzhev (RU). Light Scattering and Diffractometry Assessment of Biological Particles

12.30 Lunch break

13.30 K. Svanberg (SE). Laser Spectroscopy in the Therapy and Detection of Human Malignancies

14.30 S. Svanberg (SE). Multidisciplinary Applications of Gas in Scattering Media Absorption Spectroscopy (GASMAS)

15.30 Coffee break

16.00 S. Bagdonas (LT). Spectroscopy of Biological Tissues In Vivo

4 PROGRAMME

Wednesday 28 August

Challenging Problems of Biophotonics

09.00 J. Popp (DE). Linear- and Non-linear Raman Microspectroscopy for Biomedical Analysis

10.00 D. Sampson (AUS). Optical Coherence Tomography: How It Works, What It Can Do and Its Pitfalls

11.00 Coffee break

11.30 I. Meglinski (NZ). Monte Carlo Modelling for the Needs of Biophotonics and Biomedical Optics

12.30 R. Rotomskis (LT), R. Rudys (LT). Spectroscopy of Quantum Dot-biological Active Molecule Complex Formation

13.30 Lunch break

14.30 V. Tuchin (RU). Tissue Optics and Optical Clearing15.30 V. Khranovskyy (SE). Publication Strategy for Young Researchers

16.30 Coffee break

16.45 Conclusion of the Training course

5PROGRAMME

Conference (Aula Magnum, Raina Blvd. 19)

Thursday 29 August

08.00 Registration08.45 Opening of the Conference

Challenging Problems of Biophotonics

09.00–13.30 Invited Presentations

09.00 J. Popp (DE). Raman Spectroscopy – an Essential Tool for Modern Biophotonic Research

09.40 V. Tuchin (RU). Nanobiophotonics: Skin Protection, Diagnostics and Therapy10.20 K. Wardell (SE). Biomedical Optics in Neurosurgery

11.00 Coffee break

11.30 I. Meglinsky (NZ). Polarization and Its Use for Cancer/Tissue Diagnostics12.10 K. Svanberg (SE). Diagnostics and Treatment of Tumours Using Laser Techniques12.50 S. Andersson-Engels (SE). Upconverting Nanoparticles as a Novel Contrast Agent

in Fluorescence Diagnostics

13.30 Lunch break

14.30–16.00 Oral Presentations

14.30 S. Avtzi, A. Zacharopoulos, G. Zacharakis. Fabrication and Characterization of a 3-D Non-Homogeneous Tissue Like Mouse Phantom for Optical Imaging

14.45 S. Fomins, M. Ozolinsh. Modelling the Appearance of Chromatic Environment Using Hyperspectral Imaging

15.00 D. Khoptyar, A. A. Subash, M. Saleem, O. H. A. Nielsen, S. Andersson-Engels. Wide-bandwidth Photon Time of Flight Spectroscopy for Biomedical and Pharmaceutical Applications

15.15 D. Jakovels, I. Lihacova, I. Kuzmina, J. Spigulis. Application of Principal Component Analysis to Multispectral Imaging Data for Evaluation of Pigmented Skin Lesions

15.30 L. Vidovic, M. Milanic, B. Majaron. Assessment of Hemoglobin Dynamics in Traumatic Bruises Using Temperature Depth Profiling

15.45 M. Matulionyte, R. Marcinonyte, R. Rotomskis. Accumulation of Photoluminescent MES-Capped Gold Nanoparticles in MiaPaCa-2 Cancer Cells

16.00 Coffee break

16.30–18.00 Poster Session

6 PROGRAMME

Friday 30 August

Biophotonic Medical Sensors


09.00 D. Sampson (AUS). A Microscope in Needle, and Its Applications in Medicine09.40 G. Salerud (SE). Biophotonic Assessment of Skin Morphology, Perfusion and

Oxygenation in Healthy Newborns and Premature Children10.20 A. Priezzhev (RU). Effect of Nanodiamonds on Blood Microrheology

at In Vitro and In Vivo Administration

11.00 Coffee break

11.30 J. Spigulis (LV). Optical Non-contact Skin Sensors12.10 R. Rotomskis (LT). Up-converting Nanoparticles: Merits and Challenges

in Cancer Diagnostic and Therapy11.50 S. Bagdonas (LT). Spectrometry and Reflectometry of Biological Tissues

for Diagnostic Purposes

13.30 Lunch break


14.30 B. Majaron, L. Vidovic, M. Milanic, W. Jia, J. S. Nelson. Determination of the Maximal Safe Laser Radiant Exposure for Human Skin Using Pulsed Photothermal Radiometry

14.45 I. Yanina, N. A. Trunina, V. V. Tuchin. Detection of Phase Transition of Adipose Tissue by Spectral OCT Refractive-Index Measurement

15.00 E. Volkova, V. I. Kochubey, J. G. Konyukhova, A. A. Skaptsov. Effect of Biological Environment on Luminescence of ZnCdS Nanoparticles

15.15 L. Angelova, E. Borisova, Al. Zhelyazkova, M. Keremedchiev, B. Vladimirov. Fluorescence Spectroscopy of Gastrointestinal Tumours – In Vitro Studies and In Vivo Clinical Applications

15.30 D. Bukowska, M. Szkulmowski, M. Wojtkowski. Study of Blood Flow Behaviour in Microfluidics Device Using Spectral and Time Domain Optical Coherence Tomography

15.45 N. Talaykova, A. L. Kalyanov, V. V. Lychagov, V. P. Ryabukho, L. I. Malinova. Change Dynamics of RBC Morphology after Injection Glucose for Diabetes by Diffraction Phase Microscope

15.30 Coffee break

16.00 U. Rubins, J. Spigulis, A. Miscuks. Application of Colour Magnification Technique for Revealing Skin Microcirculation Changes under Regional Anaesthetic Input

16.15 A. Tereshchenko, R. Viter, I. Konup, V. Smyntyna, S. Geveliuk, V. Ivanitsa. TiO2 Optical Sensor for Amino Acid Detection

16.30 K. Kanders, A. Grabovskis, Z. Marcinkevics, J.I. Aivars. Assessment of Conduit Artery Vasomotion Using Photoplethysmography

7PROGRAMME

16.45 D. Sodzel, V. Khranovskyy, E. Kolesneva, L. Dubovskaya, R. Yakimova. Hydrogen Peroxide and Glucose Biosensor Based on Photoluminescence Quenching of ZnO Nanoparticles

17.00 M. Mousavi. Novel Combined Fluorescence/Reflectance Spectroscopy System for Guiding Brain Tumor Resections: Confirmation of Capability in Lab Experiments

17.15 R. Rudys, V. Khranovskyy, E. Kolesneva, L. Dubovskaya, R. Yakimova. Application of FLIM for Diagnostic Imaging of Sensitized Tissues

19.00 Conference Dinner

Saturday 31 August

Biophotonic Environmental Sensors


09.00 S. Svanberg (SE). Probing Molecules on Different Length Scales – From Environmental Monitoring to Biophotonics

09.40 M. Mak (SE). State of Art of Biosensors10.20 R. Viter (UA). Metal Oxide Nanostructures for Sensors and Biosensors

11.00 Coffee break

11.30 S. Balme (FR). Confocal Microscopy for Biosensor Applications12.10 V. Khranovskyy (SE). Application of Zinc Oxide for Optical Biosensing

Technologies 12.50 N. Starodub (UA). Optical Immune Biosensors Based on the SPR and TIRE:

Problems and Perspectives of their Practical Application at the Registration of Some Biochemical Parameters.

13.30 Lunch break


14.30 F. Vanholsbeeck, S. Swift, E. Bogomolny. Near Real Time, Accurate, and Sensitive Microbiological Safety Monitoring Using an All-Fibre Spectroscopic Fluorescence System

14.45 K. Shavanova, M. V. Taran, O. A. Marchenko, N. F. Starodub. Express Control of Plants General State by Using the New Generation of the Instrumental Tools

15.00 N. Slyshyk, N. F. Starodub. Structured Nano-Porous Silicon as Novel Transducer at Control of Mycotoxins in Environmental Objects

15.15 R. Sonko, K. Lopatko, N. Starodub. Effect of Solutions of Ferum and Zinc Nano-particles on the Plant Photosynthetic Activity

15.30 Coffee break

16.00 Closing remarks: Biophotonics Round Table

8 PROGRAMME

Poster Presentations

1. L. Asare. Signal Analysis of Multi-spectral Photoplethysmograph Biosensor.2. A. Bekina, V. Garancis, U. Rubin, E. Zaharans, J. Zaharans, L. Elste, J. Spigulis.

Signal Analysis of Multi-spectral Photoplethysmograph Biosensor.3. М. А. Bezuglyi, N. V. Bezuglaya. Ellipsoidal Reflectors in Biomedical Diagnostic.4. N. V. Bezuglaya, М. А. Bezuglyi. Spatial Photometry of Scattered Radiation by

Biological Objects.5. M. Canpolat, T. Denkceken, A. Akman, E. Alpsoy, R. Tuncer, M. Akyuz, M. Baykara,

S. Yucel, I. Bassorgun, M. A. Ciftcioglu, G. A. Gokhan, E. Inanc Gurer, E. Pestereli, S. Karaveli. Elastic Light Single-Scattering Spectroscopy for Detection of Dysplastic Tissues.

6. B. Choiński. A Program to Assist in Recognition of Emotional States.7. M. O. Eriksson, Z. N. Urgessa, J. R. Botha, K. F. Karlsson, P. Bergman, P. O. Holtz.

Optical Properties of ZnO Nanorods Grown by Chemical Bath Deposition.8. S. Fomins, I. Zakutajeva, M. Ozolinsh. Identification of Deposits on Contactlens

Surface.9. R. Fuksis, M. Pudzs, R. Ruskuls, T. Eglitis, D. Barkans, M. Greitans. Bi-Spectral

Palm Image Acquisition for Person Recognition.10. O. A. Izotova, A. L. Kalyanov, V. V. Lychagov. Correlation Mapping Method of OCT

for Visualization Blood Vessels in Brain. 11. D. Jakovels, A. Lihachev, J. Spigulis, S. Satkauskas, M. Tamosiunas, C. W. Lo,

W. S. Chen. Assessment of Efficiencies of Electroporation and Sonoporation Methods by Fluorescence RGB Imaging Method.

12. M. Jedrzejewska-Szczerska. Low-coherent Measurement Method of Human Blood Hematocrit.

13. K. Karpienko, M. S. Wrobel. Reliability and Validity of Optoelectronic Method for Biophotonical Measurements.

14. A. Kuznetsov, A. Frorip, M. Ots-Rosenberg, A. Sunter. Blue Autofluorescence of Biological Fluids and Carbon Nanodots and Its Eventual Use in Clinical Praxis.

15. A. Lihachev, I. Ferulova, J. Spigulis. Fluorescence Lifetime Spectroscopy: Potential for In-vivo Estimation of Skin Fluorophores Changes after Low Power Laser Treatment.

16. A. Lihachev, M. Tamosiunas, S. Satkauskas, J. Spigulis. Fluorescence Spectroscopy for Estimation of Anticancer Drug Sonodestruction in Cell Culture.

17. I. Lihacova, A. Derjabo, A. Bekina, J. Zaharans, J. Spigulis. Development of Multispectral Imaging Method for Skin Pathology Diagnostics.

18. M. Mantineo, A. M. Morgado, J. P. Pinheiro. Methodology for Assessment of Low Level Laser Therapy (LLLT) Irradiation Parameters in Muscle Inflammation Treatment.

19. P. Naglic, L. Vidovic, M. Milanic, L. L. Randeberg, B. Majaron. Applicability of Diffusion Approximation in Analysis of Diffuse Reflectance Spectra from Healthy Human Skin.

20. I. Saknite, E. Kviesis, J. Spigulis. Water Detection In Skin By Dual-Band Photodiodes

9PROGRAMME

21. A. Shaharin, E. K. Svanberg, I. Ellerstrom, A. A. Subash, D. Khoptyar, S. Andersson-Engels, J. Akeson. Muscle Tissue Saturation in Humans Studied with Two Non-invasive Optical Techniques: a Comparative Study.

22. L. Surazynski, Sz. Buda, M. Jedrzejewska-Szczerska. Biophotonic Sensor of Small Changes in the NaCl Concentration in Aqueous Solution.

23. M. V. Taran, N. F. Starodub, A. M. Katsev, M. Guidotti, V. D. Khranovskyy, A. A. Babanin, M. D. Melnychuk. Biocidal Effects of Silver and Zink Oxide Nanoparticles on the Bioluminescent Bacteria.

24. N. Lippok, S. Murdoch, F. Vanholsbeeck. Micron Scale Dispersion Mapping for Tissue Recognition in Optical Coherence Tomography.

25. K. Volceka, L. Ozolina-Moll, E. Svampe, J. Zaharans, E. Zaharans, Z. Marcinkevics. A Development of Multispectral Approach to Evaluate the Cardiometabolic Risk Related to Alterations in Body Composition.

26. Z. Xie, H. Xie, M. Mousavi, M. Brydegaard, J. Axelsson, S. Andersson-Engels. Novel Combined Fluorescence/Reflectance Spectroscopy System for Guiding Brain Tumor Resections – Hardware Considerations.

27. A. Zhelyazkova, E. Borisova, L. Angelova, E. Pavlova, M. Keremedchiev. Excitation-Emission Matrices Measurements of Human Cutaneous Lesions – Tool for Fluorescence Origins Evaluation.

28. V. Zubkovs, F. Jamme, S. Kascakova, F. Chiappini, F. Le Naour, M. Refregiers. Multimodal Imaging: Combined DUV, SHG and TPEF Microscopy.

10 CONTENT

ABSTRACTS

CONTENT

INVITED PRESENTATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

J. PoppRaman Spectroscopy an Essential Tool for Modern Biophotonic Research . . . . . . . . . 15

V. V. TuchinNanobiophotonics: Skin Protection, Diagnostics and Therapy . . . . . . . . . . . . . . . . 16

K. WardellBiomedical Optics in Neurosurgery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

I. Meglinski Polarization and Its Use for Cancer/Tissue Diagnostics . . . . . . . . . . . . . . . . . . . . . . 18

K. SvanbergDiagnostics and Treatment of Tumours Using Laser Techniques . . . . . . . . . . . . . . . 19

S. Andersson-Engels Upconverting Nanoparticles as a Novel Contrast Agent in Fluorescence Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

D. D. Sampson, D. Lorenser, B. C. Quirk, R. W. Kirk, L. Scolaro, A. Curatolo, X. Yang, R. A. McLaughlinA Microscope in Needle, and Its Applications in Medicine and Biology . . . . . . . . . . . 21

S. Fredly, K. Kvernebo, E. G. SalerudBiophotonic Assessment of Microcirculation in Healthy Newborn Children . . . . . . . . 22

A. PriezzhevEffect of Nanodiamonds on Blood Microrheology at In Vitro and In Vivo Administration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

J. Spigulis, D. Jakovels, U. Rubins, A. Lihacev, I. Kuzmina, I. LihacovaOptical Non-contact Skin Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

R. RotomskisUp-converting Nanoparticles: Merits and Challenges in Cancer Diagnostics and Therapy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

S. BagdonasSpectrometry and Reflectometry of Biological Tissues for Diagnostic Purposes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

11CONTENT

S. SvanbergProbing Molecules on Different Length Scales – From Environmental Monitoring to Biophotonics . . . . . . . . . . . . . . . . . . . . . . . . . 27

M. MakPhotometric Nanolabels for Biosensors and Bioassays . . . . . . . . . . . . . . . . . . . . . . 28

R. ViterUse of TiO2 Photoluminescence for Salmonella Detection . . . . . . . . . . . . . . . . . . . 29

S. Balme, J.-M. Janot Confocal Fluorescence Spectroscopy for Bio-sensor Applications and Potentialities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

V. KhranovskyyApplication of Zinc Oxide for Optical Biosensing Technologies . . . . . . . . . . . . . . . . 31

N. F. Starodub Optical Immune Biosensors Based on the SPR and TIRE: Problems and Perspectives of their Practical Application at the Registration of Some Biochemical Parameters . . . . . . . . . . . . . . . . . . . . . . . 32

ORAL PRESENTATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

S. Avtzi, A. Zacharopoulos, G. ZacharakisFabrication and Characterization of a 3-D Non-Homogeneous Tissue like Mouse Phantom for Optical Imaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

S. Fomins, M. Ozolinsh Modelling the Appearance of Chromatic Environment Using Hyperspectral Imaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

D. Khoptyar, A. A. Subash, M. Saleem, O. H. A. Nielsen, S. Andersson-EngelsWide-bandwidth Photon Time of Flight Spectroscopy for Biomedical and Pharmaceutical Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

D. Jakovels, I. Lihacova, I. Kuzmina, J. SpigulisApplication of Principal Component Analysis to Multispectral Imaging Data for Evaluation of Pigmented Skin Lesions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

L. Vidovic, M. Milanic, B. MajaronAssessment of Hemoglobin Dynamics in Traumatic Bruises Using Temperature Depth Profiling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

M. Matulionyte, R. Marcinonyte, R. RotomskisAccumulation of Photoluminescent MES-Capped Gold Nanoparticles in MiaPaCa-2 Cancer Cells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

B. Majaron, L. Vidovic, M. Milanic, W. Jia, J. S. NelsonDetermination of the Maximal Safe Laser Radiant Exposure for Human Skin Using Pulsed Photothermal Radiometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

12 CONTENT

I. Yu. Yanina, N. A. Trunina, V. V. Tuchin Detection of Phase Transition of Adipose Tissue by Spectral OCT Refractive-Index Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

E. K. Volkova, V. I. Kochubey, J. G. Konyukhova, A. A. SkaptsovEffect of Biological Environment on Luminescence of ZnCdS Nanoparticles . . . . . . . . 41

L. Angelova, E. Borisova, Al. Zhelyazkova, M. Keremedchiev, B. VladimirovFluorescence Spectroscopy of Gastrointestinal Tumours – In Vitro Studies and In Vivo Clinical Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

D. Bukowska, M. Szkulmowski, M. WojtkowskiStudy of Blood Flow Behaviour in Microfluidics Device Using Spectral and Time Domain Optical Coherence Tomography . . . . . . . . . . . . . . . . . . . . . . . . . . 43

N. A. Talaykova, A. L. Kalyanov, V. V. Lychagov, V. P. Ryabukho, L. I. MalinovaChange Dynamics of RBC Morphology after Injection Glucose for Diabetes by Diffraction Phase Microscope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

U. Rubins, J. Spigulis, A. MiscuksApplication of Colour Magnification Technique for Revealing Skin Microcirculation Changes under Regional Anaesthetic Input . . . . . . . . . . . . . . . . . 45

A. Tereshchenko, R. Viter, I. Konup, V. Smyntyna, S. Geveliuk, V. Ivanitsa TiO2 Optical Sensor for Amino Acid Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

K. Kanders, A. Grabovskis, Z. Marcinkevics, J. I. AivarsAssessment of Conduit Artery Vasomotion Using Photoplethysmography . . . . . . . . . 47

D. Sodzel, V. Khranovskyy, E. Kolesneva, L. Dubovskaya, R. YakimovaHydrogen Peroxide and Glucose Biosensor Based on Photoluminescence Quenching of ZnO Nanoparticles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

M. MousaviNovel Combined Fluorescence/Reflectance Spectroscopy System for Guiding Brain Tumor Resections: Confirmation of Capability in Lab Experiments . . . . . . . . . . 49

R. Rudys, S. Bagdonas, G. Kirdaite, R. RotomskisApplication of FLIM for Diagnostic Imaging of Sensitized Tissues . . . . . . . . . . . . . . . 50

F. Vanholsbeeck, S. Swift, E. BogomolnyNear Real Time, Accurate, and Sensitive Microbiological Safety Monitoring Using an All-Fibre Spectroscopic Fluorescence System . . . . . . . . . . . . . . . . . . . . . 51

K. E. Shavanova, M. V. Taran, O. A. Marchenko, N. F. StarodubExpress Control of Plants General State by Using the New Generation of the Instrumental Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

N. F. Slyshyk, N. F. StarodubStructured Nano-Porous Silicon as Novel Transducer at Control of Mycotoxins in Environmental Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

R. Sonko, K. Lopatko, N. StarodubEffect of Solutions of Ferum and Zinc Nano-particles on the Plant Photosynthetic Activity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

13CONTENT

POSTER PRESENTATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

L. AsareSignal Analysis of Multi-spectral Photoplethysmograph Biosensor . . . . . . . . . . . . . . 55

A. Bekina, V. Garancis, U. Rubins, E. Zaharans, J. Zaharans, L. Elste, J. SpigulisMultimodal Device for Assessment of Skin Malformations . . . . . . . . . . . . . . . . . . . 56

М. А. Bezuglyi, N. V. BezuglayaEllipsoidal Reflectors in Biomedical Diagnostic . . . . . . . . . . . . . . . . . . . . . . . . . . 57

N. V. Bezuglaya, М. А. BezuglyiSpatial Photometry of Scattered Radiation by Biological Objects . . . . . . . . . . . . . . 58

M. Canpolat, T. Denkceken, A. Akman, E. Alpsoy, R. Tuncer, M. Akyuz, M. Baykara, S. Yucel, I. Bassorgun, M. A. Ciftcioglu, G. A. Gokhan, E. Inanc Gurer, E. Pestereli, S. KaraveliElastic Light Single-Scattering Spectroscopy for Detection of Dysplastic Tissues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

B. ChoinskiA Program to Assist in Recognition of Emotional States . . . . . . . . . . . . . . . . . . . . . 60

M. O. Eriksson, Z. N. Urgessa, J. R. Botha, K. F. Karlsson, P. Bergman, P. O. HoltzOptical Properties of ZnO Nanorods Grown by Chemical Bath Deposition . . . . . . . . . 61

S. Fomins, I. Zakutajeva, M. Ozolinsh Identification of Deposits on Contactlens Surface . . . . . . . . . . . . . . . . . . . . . . . . 62

R. Fuksis, M. Pudzs, R. Ruskuls, T. Eglitis, D. Barkans, M. GreitansBi-Spectral Palm Image Acquisition for Person Recognition . . . . . . . . . . . . . . . . . . 63

O. A. Izotova, A. L. Kalyanov, V. V. Lychagov Correlation Mapping Method of OCT for Visualization Blood Vessels in Brain . . . . . . . 64

D. Jakovels, A. Lihachev, J. Spigulis, S. Satkauskas, M. Tamosiunas, C. W. Lo, W. S. ChenAssessment of Efficiencies of Electroporation and Sonoporation Methods by Fluorescence RGB Imaging Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

M. Jedrzejewska-SzczerskaLow-coherent Measurement Method of Human Blood Hematocrit . . . . . . . . . . . . . 66

K. Karpienko, M. S. WrobelReliability and Validity of Optoelectronic Method for Biophotonical Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

A. Kuznetsov, A. Frorip, M. Ots-Rosenberg, A. Sunter Blue Autofluorescence of Biological Fluids and Carbon Nanodots and Its Eventual Use in Clinical Praxis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

A. Lihachev, I. Ferulova, J. SpigulisFluorescence Lifetime Spectroscopy: Potential for In-vivo Estimation of Skin Fluorophores Changes after Low Power Laser Treatment . . . . . . . . . . . . . . . 69

14 CONTENT

A. Lihachev, M. Tamosiunas, S. Satkauskas, J. Spigulis Fluorescence Spectroscopy for Estimation of Anticancer Drug Sonodestruction in Cell Culture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

I. Lihacova, A. Derjabo, A. Bekina, J. Zaharans, J. SpigulisDevelopment of Multispectral Imaging Method for Skin Pathology Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

M. Mantineo, A. M. Morgado, J. P. PinheiroMethodology for Assessment of Low Level Laser Therapy (LLLT) Irradiation Parameters in Muscle Inflammation Treatment . . . . . . . . . . . . . . . . . . . 72

P. Naglic, L. Vidovic, M. Milanic, L. L. Randeberg, B. MajaronApplicability of Diffusion Approximation in Analysis of Diffuse Reflectance Spectra from Healthy Human Skin . . . . . . . . . . . . . . . . . . . . 73

I. Saknite, E. Kviesis, J. SpigulisWater Detection in Skin by Dual-Band Photodiodes . . . . . . . . . . . . . . . . . . . . . . . 74

A. Shaharin, E. K. Svanberg, I. Ellerstrom, A. A. Subash, D. Khoptyar, S. Andersson-Engels, J. AkesonMuscle Tissue Saturation in Humans Studied with Two Non-invasive Optical Techniques: a Comparative Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

L. Surazynski, Sz. Buda, M. Jedrzejewska-Szczerska Biophotonic Sensor of Small Changes in the NaCl Concentration in Aqueous Solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

M. V. Taran, N. F. Starodub, A. M. Katsev, M. Guidotti, V. D. Khranovskyy, A. A. Babanin, M. D. MelnychukBiocidal Effects of Silver and Zink Oxide Nanoparticles on the Bioluminescent Bacteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

N. Lippok, S. Murdoch, F. VanholsbeeckMicron Scale Dispersion Mapping for Tissue Recognition in Optical Coherence Tomography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

K. Volceka, L. Ozolina-Moll, E. Svampe, J. Zaharans, E. Zaharans, Z. MarcinkevicsA Development of Multispectral Approach to Evaluate the Cardiometabolic Risk Related to Alterations in Body Composition . . . . . . . . . . . 79

Z. Xie, H. Xie, M. Mousavi, M. Brydegaard, J. Axelsson, S. Andersson-EngelsNovel Combined Fluorescence/Reflectance Spectroscopy System for Guiding Brain Tumor Resections – Hardware Considerations . . . . . . . . . . . . . . . . . . . . . . . 80

A. Zhelyazkova, E. Borisova, L. Angelova, E. Pavlova, M. KeremedchievExcitation-Emission Matrices Measurements of Human Cutaneous Lesions – Tool for Fluorescence Origins Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

V. Zubkovs, F. Jamme, S. Kascakova, F. Chiappini, F. Le Naour, M. RéfrégiersMultimodal Imaging: Combined DUV, SHG and TPEF Microscopy . . . . . . . . . . . . . . 82

15INVITED PRESENTATIONS

INVITED PRESENTATIONS

Raman Spectroscopy an Essential Tool for Modern Biophotonic Research

J. Popp1, 2

1 Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich-Schiller University, Jena, Germany 2 Institute of Photonic Technology, Jena, Germany

E-mail: [email protected]

A rapid increase of applications of Raman spectroscopy to address biophotonic questions has been observed lately. Here, we report various examples of our latest results concerning the application of linear and nonlinear Raman microspectroscopy for clinical diagnosis. First, the unique potential of Raman microspectroscopy for an online identification of microorganisms is highlighted. The rapid identification of pathogens based in their characteristic Raman fingerprint is of great relevance for an efficient medical diagnosis (e.g. rapid identification of pathogens in urine samples) or air- and soil monitoring (e.g. identification of anthrax endospores embedded in complex matrices). The implementation of Raman spectroscopy and optical traps in a microfluidic chip allows for Raman activated cell sorting which offers large potential for an automated classification of cells like e.g. circulating tumour cells. Besides single cells, the investigation of whole tissue sections like biopsy specimens by means of Raman-microspectroscopy aiming for an early disease diagnosis will be shown. Furthermore, first steps towards in-vivo Raman spectroscopy utilizing novel Raman fiber probes for an intravascular monitoring of the artheriosclerotic plaque in living rabbits will be presented. The rather long acquisition times of Raman imaging can be reduced by utilizing non-linear Raman approaches like CARS (coherent anti-Stokes Raman scattering). In order to improve the diagnostic result CARS microscopy can be easily combined with second harmonic generation (SHG) and two-photon fluorescence (TPF) microscopy. The diagnostics potential of a compact CARS/SHG/TPF multimodal microscope as compared to conventional histopathological images will be shown for the examples of atherosclerosis and cancer.

Acknowledgements

Financial support of the EU, the ”Thüringer Kultusministerium”, the ”Thüringer Aufbaubank”, the Federal Ministryof Education and Research, Germany (BMBF), the German Science Foundation, the Fonds der Chemischen Industrie and the Carl-Zeiss Foundation are greatly acknowledged.

16 INVITED PRESENTATIONS

Nanobiophotonics: Skin Protection, Diagnostics and Therapy

V. V. Tuchin Saratov State University, Saratov, Russia

Institute of Precise Mechanics and Control RAS, Saratov, RussiaUniversity of Oulu, FinlandE-mail: [email protected]

The use of photonic nanotechnologies in medicine is a rapidly emerging and potentially powerful approach for tissue protection, disease detection and treatment. This paper will focus on state-of-the-art research in the field of tissue and cell nanophotonics with particular emphasis on the exogenous nanoparticle (NP) delivery, optical control and treatment via selective and localized laser-induced overheating and photothermal/photodynamic cell damage [1–10]. Fundamentals of theranostics based on interaction between light, cells, tissues, and inserted nanoparticles will be discussed [2]. These interactions will include optical, photothermal, photoacoustic, and photochemical phenomena with the aim of cellular diagnostics and treatment in living organisms. The following main topics will be discussed: technologies and examples for NP delivery into a target tissue location [3–5], applications of plasmon-resonant gold nanoparticles (GNPs) to photothermal cell optoporation [8] and bacteria killing [9]; NP image velocimetry and temperature measurements in laser-trapped NP flows; in vivo integrated optical flow cytometry at cell labeling by NPs [1]; OCT and two-photon microscopy monitoring of NP diffusion within soft and hard tissues [6]; light-assisted microbial ingibition using photothermal and photocatalytic NPs and photodynamic dye compositions [9]; FDTD modeling of optical and thermal fields of NPs incorporated into cells and tissues [7, 8].

Acknowledgements

I would like to thank all my colleagues and collaborators, especially Yu.A. Avetisyan, E. A. Genina, A. N. Bashkatov, M. E. Darvin, L. E. Dolotov, I. V. Fedosov, V. I. Kochubey, B. N. Khlebtsov, N. G. Khlebtsov, K. Kordas, J. Lademann, A. P. Popov, A. Tárnok, G. S. Terentyuk, V. P. Zharov, N. A. Trunina, E. S. Tuchina, A. P. Popov, A. N. Yakunin, for their input in these studies.

References

[1] V. V. Tuchin, A. Tárnok, and V.P. Zharov, Cytometry A 79A (10), 737–745 (2011).[2] N. Khlebtsov, V. Bogatyrev, L. Dykman, et al. Theranostics 3(3) (2013).[3] E. A. Genina, A. N. Bashkatov, V. V. Tuchin, et al., J. Biomed. Opt. 18 (2013).[4] G. S. Terentyuk, E. A. Genina, A. N. Bashkatov, et al., Quantum Electronics 42(6), 471–477 (2012).[5] E. A. Genina, G. S. Terentyuk, B. N. Khlebtsov, et al., Quantum Electronics 42 (6) 478–483 (2012).[6] N. A. Trunina, A. P. Popov, J. Lademann, et al., Proc. SPIE 8427, 8427OY-1-6 (2012).[7] Y. A. Avetisyan, A. N. Yakunin, and V. V. Tuchin, Appl. Opt. 51, C88–C94 (2012).[8] Y. A. Avetisyan, A. N. Yakunin, and V. V. Tuchin, J. Biophotonics 5(10), 734–744 (2012).[9] B. N. Khlebtsov, E. S. Tuchina, V. A. Khanadeev, et al., J. Biophotonics 6 (4), 338–351 (2013). [10] A. Sarkar, A. Shchukarev, A.-R. Leino, et al., Nanotechnology 23, 475711-1-8 (2012).


Biomedical Optics in Neurosurgery

K. WardellDepartment of Biomedical Engineering, Linkoping University, Linkoping Sweden


During the last decade the interest for optical brain monitoring and imaging has increased. Very few of the new optical techniques have, however, fully been adapted for clinical use in neurosurgery and neurointensive care. One exception is the conventional light microscope used during neurosurgical procedures such as tumour resection. The microscopy technique has recently been modified with video recording and filters for various wavelength intervals. Among these the ultraviolet region is suitable for enhancement of malignant tumour by means of protoporphyrine IX (PpIX) induced fluorescence [1]. We have developed a fluorescence monitoring system, the Optical Touch Pointer (OTP), which uses an fibre optical probe for PpIX detection [2]. The OTP can be used in combination with intraoperativ ultrasound navigation during tumour resection [3] and is now also evaluated together with fluorescence microscopy. Preliminary data shows that the OTP is more sensitive in detecting PpXI at the tumour border than fluorescence microscopy. Other advantages with the OTP is that the signal can be quantified and measurements done inside the tumour. Another example of an available brain monitoring technique is near infrared spectroscopy sometimes used for measurement of oxygenation in the neonatal intensive care. For the neuro intensive care in adults we are developing a concept for recording of cerebral blood flow parameters by means of combined diffuse reflectance spectroscopy (DRS) and laser Doppler perfusion monitoring (LDPM). Some major issues for this application is the probe design and the safety requirements necessary for invasive, long term monitoring of critically ill patients. The method has so far been evaluated intraoperatively during tumour resection and biopsies [4]. DRS and LDPM have also been used in relation to deep brain stimulation (DBS) implantations. Typical “optical trajectories” have been defined towards two common DBS targets used for implantation in patients with movement disorders [5]. This study also shows that the blood perfusion signal from the LDPM-system has a potential to indicate vessel structures in the vicinity along the trajectory. The relation between the blood perfusion signal and vessels will be further explored and the spectral contents relating to specific chromophores investigated. In summary, optical techniques have great potential for delineation of tumour borders and measurements of cerebral blood flow parameters in neurosurgery but further evaluation and clinical adaptations of the respective techniques are necessary.

References

[1] Stummer, W., et al., Fluorescence-guided surgery with 5-aminolevulinic acid for resection of malignant glioma: a randomised controlled multicentre phase III trial. Lancet Oncol, 2006. 7(5): p. 392–401.

[2] Haj-Hosseini, et al., Optical touch pointer for fluorescence guided glioblastoma resection using 5-aminolevulinic acid. Lasers Surg Med, 2010. 42(1): p. 9–14.

[3] Richter, J. C., et al., Fluorescence spectroscopy measurements in ultrasonic navigated resection of malignant brain tumors. Lasers Surg Med, 2011. 43(1): p. 8–14.

[4] Rejmstad, P., et al., Combined laser Doppler and reflectance spectroscopy measurements during brain surgery, in CARS, Accepted. 2013: Heidelberg.

[5] Wårdell, K., et al., Relationship between laser Doppler signals and anatomy during deep brain stimulation electrode implantation toward the ventral intermediate nucleus and subthalamic nucleus. Neurosurgery, 2013. 72 (2 Suppl Operative): p. 127–140.


Polarization and Its Use for Cancer/Tissue Diagnostics

I. Meglinski Department of Physics, University of Otago, New Zeeland


The field of cancer diagnostics is rapidly expanding, and as diagnostic technology improves so does the ability to detect and identify the many different types and sub-types of cancer. For the successful treatment the early detection of cancer is extremely important. However, during early cancer onset it is quite difficult for pathologist to differentiate between tissues that may be neoplastic versus normal tissue undergoing dysplastic changes that is unlikely to become neoplastic. Currently, the most widely used methodology for cancer diagnosis is histological analysis with further microscopy investigation. Despite the best laboratory practice the rate of conclusive diagnosis by histological analysis for a range of cancers, including cervical, bladder, skin and oral cancer, is only 65–75%. We demonstrated that circular and/or elliptical polarized light scattered within the tissues is highly sensitive to the presence of cancer cells and their aggressiveness in tissues. Moreover, we found that the position of Stokes vector of scattered light on the Poincaré sphere displays the successive stages of colorectal cancer. We use the sphere as a convenient tool for analysis the state of polarization of light scattered within biological tissue; navigating by Poincaré sphere (similar as by terrestrial globe, using longitude and latitude as in GPS navigator) to monitor/determine polarisation properties and condition of biological tissues. We envisage that this research will enable the development of a new revolutionary diagnostic tool. For example, this technique could help in confirming the presence of early stages of prostate, melanoma or colon cancer in situ in doubtful cases.


Diagnostics and Treatment of Tumours Using Laser Techniques

K. SvanbergDepartment of Oncology, Lund University Hospital, Lund University, Lund, SwedenCentre for Optical and Electromagnetic Research, South China Normal University

University City Campus, Guangzhou, ChinaE-mail: [email protected]

Applications of optical and laser spectroscopy to the medical field, including photodynamic therapy (PDT) and laser-induced fluorescence diagnostics (LIF) for cancer treatment and diagnostics, respectively, will be presented. Photodynamic therapy in conjunction with LIF for demarcation of the treatment target area will be discussed. To overcome the limited light penetration in superficial illumination interstitial delivery (IPDT) with the light transmitted to the tumour via optical fibres has been developed. Interactive feed-back dosimetry is of importance for optimising this modality and such a concept has been developed and will be presented. Special emphasis will be on prostate cancer therapy with interstitial PDT. The most important prognostic factor for cancer patients is early tumour discovery. If malignant tumours are detected during the non-invasive stage, most tumours show a high cure rate of more than 90 %. There is a variety of conventional diagnostic procedures, such as x.X-ray imaging. More advanced results are given in computerised investigations, such as CT-, MRI- or PET-scanning. Laser-induced fluorescence (LIF) for tissue characterisation is a technique that can be used for monitoring the biomolecular changes in tissue under transformation from normal to dysplastic and cancer tissue before structural tissue changes are seen at a later stage. The technique is based on UV or near-UV illumination for fluorescence excitation. The fluorescence from endogenous chromophores in the tissue alone, or enhanced by exogenously administered tumour seeking substances can be utilised. The technique is non-invasive and gives the results in real-time. LIF can be applied for point monitoring or in an imaging mode for larger areas, such as the vocal cords or the portio of the cervical area. The possibility to combine LIF and PDT will be discussed and illustrated with clinical examples from many specialities, such as dermatology, gynaecology and laryngology. A new method where free gas (oxygen or water vapour) in the human sinus cavities is detected will be described. The technique is based on gas absorption spectroscopy in scattering media (GASMAS). The method can also be used to study the gas exchange in between the nasal cavity and the different sinuses in the facial region. The GASMAS technique might also be used for detecting the oxygen distribution in the lungs of prematurly born infants. Preliminary studies have been performed showing encouraging results.


Upconverting Nanoparticles as a Novel Contrast Agent in Fluorescence Diagnostics

S. Andersson-Engels Department of Physics, Lund University, SwedenE-mail: [email protected]

Optical imaging has become an increasingly important tool in drug discovery and development, as it provides a tool for minimally invasive monitoring. In vivo alterations at the organ, tissue, cell or even molecular level can be monitored in animal studies to improve the understanding of basic physiology. Studies over days, weeks and months on each individual are possible. The main limitations of fluorescence imaging of small animal are tissue autofluorescence, poor resolution and poor light penetration, making it difficult to image deeply located regions with high sensitivity. Upconverting nanoparticles (UCNPs) have a potential to overcome these limitations by their unique properties. UCNPs are synthesized as small crystals doped with certain trivalent lanthanide ions or transition metals. Common materials are ytterbium and yttrium in combination with small amounts of other ions, like for instance erbium (Er) or thulium (Tm). Such Yb/Tm-codoped UCNPs are excited at a wavelength of around 980 nm and emit light at 800 nm. Both the excitation and emission wavelengths are close to optimal for in vivo imaging in tissue. Due to the anti-Stokes shift of the upconverting signal, the signal can be truly background-free without influence from any tissue autofluorescence. This increases drastically the signal-to-background ratio, making it possible to measure very weak signals from tissue. Another benefit of UCNP imaging is the possibility to obtain an improved spatial resolution in the recorded images. This is due to the non-linear relation between the emitted signal and the excitation power. This non-linear dependence alters the sensitivity map for the nanoparticles within the tissue.

References

[1] CT. Xu, et al. High-resolution fluorescence diffuse optical tomography developed with nonlinear upconverting nanoparticles. ACS Nano, 6(6):4788–4795, 2012.

[2] CT. Xu, et al. Upconverting nanoparticles for pre-clinical diffuse optical imaging, microscopy and sensing: Current trends and future challenges. Laser & Photonics Reviews, 2013.


A Microscope in Needle, and Its Applications in Medicine and Biology

D. D. Sampson1, 2, D. Lorenser1, B. C. Quirk1, R. W. Kirk1, L. Scolaro1, A. Curatolo1, X. Yang1, R. A. McLaughlin1

1 Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Perth, Western Australia, Australia

2 Centre for Microscopy, Characterisation & Analysis, The University of Western Australia, Perth, Western Australia, Australia


Optical fibers form an ideal building block for the design and realization of ultra-small, minimally invasive microscopic imaging and monitoring systems for use within the body. Embedding such optical probes within a rigid needle provides access to deep tissues in humans and animals that is impossible to achieve with surface-based imaging.Over the last several years, we have been developing such probes and associated imaging systems, mainly based upon optical coherence tomography. Recent technical advances include: three-dimensional imaging1, confocal microscopy in needles2, ultrathin needle probes3, extended depth of focus probes4, use of mechanical contrast – needle elastography5, hand-held scanning using magnetic-sensor navigation6, anastigmatic high-sensitivity capillary needle designs7, and the combination of OCT with fluorescence in a needle8.Beyond technical innovation, we have begun applying microscope-in-a-needle imaging to a wide variety of tissues and pathologies in animals and humans. Our initial focus is on the breast and lymph nodes (cancer)9, 10, lungs (chronic obstructive pulmonary disease models)1, 11 and skeletal muscle (muscular dystrophy).In this talk, we present these advances in engineering the optics of such systems, and in their use in 3D tissue morphological micro-imaging and probing of the micro-mechanical properties of tissue.

References

[1] B. C. Quirk, et al., “In situ imaging of lung alveoli with an optical coherence tomography needle probe,” Journal of Biomedical Optics, vol. 16, p. art. 036009 (4pp), 2011.

[2] R. S. Pillai, et al., “Deep-tissue access with confocal fluorescence microendoscopy through hypodermic needles,” Optics Express, vol. 19, pp. 7213–7221, 2011.

[3] D. Lorenser, et al., “Ultrathin side-viewing needle probe for optical coherence tomography,” Optics Letters, vol. 36, pp. 3894–3896, 2011.

[4] D. Lorenser, et al., “Ultrathin fiber probes with extended depth of focus for optical coherence tomography,” Optics Letters, vol. 37, pp. 1616–1618, 2012.

[5] K. M. Kennedy, et al., “Needle optical coherence elastography for tissue boundary detection,” Optics Letters, vol. 37, pp. 2310–2312, 2012.

[6] B. Y. Yeo, et al., “Enabling freehand lateral scanning of optical coherence tomography needle probes with a magnetic tracking system,” Biomedical Optics Express, vol. 3, pp. 1565–1578, 2012.

[7] L. Scolaro, et al., “High-sensitivity anastigmatic imaging needle for optical coherence tomography,” Optics Letters, vol. 37, pp. 5247–5249, 2012.

[8] D. Lorenser, et al., “Dual-modality needle probe for combined fluorescence imaging and three-dimensional optical coherence tomography,” Optics Letters, vol. 38, pp. 266–268, 2013.

[9] R. A. McLaughlin, et al., “Imaging of breast cancer with optical coherence tomography needle probes: Feasibility and initial results,” IEEE Journal of Selected Topics in Quantum Electronics, vol. 18, pp. 1184–1191, 2012.

[10] A. Curatolo, et al., “Ultrasound-guided optical coherence tomography needle probe for the assessment of breast cancer tumor margins,” American Journal of Roentgenology, vol. 199, pp. W520–W522, 2012.

[11] R. A. McLaughlin, et al., “Static and dynamic imaging of alveoli using optical coherence tomography needle probes,” Journal of Applied Physiology, vol. 113, pp. 967–974, 2012.


Biophotonic Assessment of Microcirculation in Healthy Newborn Children

S. Fredly1, 2, K. Kvernebo1, 2, E. G. Salerud3

1 Department of Neonatal Intensive Care, Oslo University Hospital, Ullevål, Oslo, Norway2 Faculty of Medicine, University of Oslo, Oslo, Norway

3 Department of Biomedical Engineering, Linköping University, Sweden

The maternal circulation delivers oxygen and nutrition for cell proliferation in uteri. The transition from intra- to extra-uterine life is a vulnerable phase for the newborn and after delivery; the newborn is dependent on gas exchange by the lungs, generation of increased systemic arterial perfusion pressure and redirection of central blood. Therefore we need to describe the microvascular changes during the transitional phase from fetal to neonatal circulation during the first days of life. Three different biophotonic techniques; computer assisted video microscopy (CAVM), laser Doppler perfusion (LDPM) and diffuse reflectance spectroscopy (DRS) was applied and evaluated in twenty-five healthy term newborns for the first 3 days in life. The microvascular and capillary density [lines/mm] was significantly higher (p<0.001) in the hand [13.2, 13.2, 12.4] compared with the chest [11.3, 11.0, 10.7]. Perfusion [arb. units] was significantly higher (p < 0.01) in the chest [109.1, 101.4, 100.8] in comparison to the hand [58.9, 54.3, 46.9] for all three days, while the capillary flow velocities were similar in both, with 60–70% capillaries having “continuous high flow” and 30–40% “continuous low flow”. The oxygen saturation (%) was not significantly higher (p < 0.05) in chest [88.1, 87.8, 86.7] than in hand [79.9, 82.7, 82.2].The evaluation of skin microvascular hemodynamics with the multimodal biophotonic methods CAVM, LDPM and DRS are feasible in newborns and shows reproducible data. The evaluation supplement the information for quality of delivery of oxygen for the metabolic process, necessary for growth and development in newborn babies and can be used to guide the effect of circulation treatment or respiration failure in both premature babies and newborns.


Effect of Nanodiamonds on Blood Microrheology at In Vitro and In Vivo Administration

A. Priezzhev

ABSTRACT UNAVAILABLE


Optical Non-contact Skin Sensors

J. Spigulis, D. Jakovels, U. Rubins, A. Lihacev, I. Kuzmina, I. LihacovaInstitute of Atomic Physics and Spectroscopy, University of Latvia, Riga, Latvia


Three non-contact optical technologies for in-vivo skin assessment sensors are discussed. 1. Laser exposure causes skin autofluorescence photo-bleaching (AFPB); its intensity decreases with irradiation time t accordingly to the double-exponential rule. The “fast” AFPB (when sharp intensity decrease is observed) usually takes place during the first 5–15 s of irradiation, while the “slow” AFPB continues up to several minutes. To investigate the clinical potential of photo-bleaching, a technology of imaging the skin AFPB rates was developed. The imaging setup comprised an excitation laser coupled with an optical fibre for radiation delivery, a consumer camera equipped with a band-pass filter in front of the objective and operating at a slow video-mode (2 frames/s), and a computer with image processing software. As a result, parametric images of distribution of the τ-values over the imaged skin areas have been obtained and analysed. In the regions of pigmented lesions (e.g. birthmarks or nevi) the τ1 values always exceeded those of the healthy skin, indicating to diagnostic potential of this technology. A portable skin AFPB rate measurement sensor has been developed and tested.2. Skin multispectral imaging (MSI) technology was applied for cutaneous chromophore mapping and quantitative estimation of specific skin diseases, including melanoma; it appeared helpful also for recovery monitoring of vascular malformations after the phototherapy. Clinical measurements were taken by means of a high performance MSI camera Nuance EX. (450–950 nm). Our skin MSI studies allowed proposing two modalities of distant melanoma detection. One of them is based on correlation analysis of the melanin and haemoglobin content changes compared with the healthy skin. The other method is based on comparison of a limited number of skin spectral images. Analysis of clinical data allowed defining al parameter depending on the optical densities at three selected spectral bands: ~540 nm, 650 nm and 950 nm; the parametric images show ability to distinguish melanomas from other pigmented skin lesions like birthmarks. Advantage of this approach is use of only three spectral images. Three portable MSI sensor prototypes will be regarded.3. Photoplethysmography (PPG) video-imaging was studied as a potential tool for distant mapping of skin blood perfusion. The pulsatile remission PPG signals can be detected distantly by video-imaging of skin. Any skin-reflected light, especially within the yellow-green range is slightly modulated with the heartbeat frequency due to periodic changes of the skin blood volume and the related absorption by blood haemoglobin. The video-signal consists of a number of image frames taken at a definite frame rate, e.g. 20 frames per second. If consecutive frames are compared, the reflected light intensity detected at the same image area increases/decreases with time, forming the periodic PPG signal. Specific software allows extracting the PPG pulsations from the video-signal over the whole skin image area. The amplitude of PPG peaks may differ between the image pixels due to different blood supply or perfusion of the skin tissues (especially is there is a burn or other skin damage). After proper processing, the adequate parametric maps of distribution of the PPG signal amplitude (or blood perfusion maps) can be constructed. The laboratory-made PPGI prototype device comprising a stabilized white LED illumination source and a CMOS RGB 752 × 480 pixel video-camera was successfully applied for distant anaesthesiology control during the arm surgery; good correlation between the PPG signal amplitudes and skin temperature was obtained, so the skin perfusion jump signalling about the action of anaesthetics was detected remotely.


Up-converting Nanoparticles: Merits and Challenges in Cancer Diagnostics and Therapy

R. Rotomskis1, 2

1 Biophotonics group of Laser Research Center, Faculty of Physics, Vilnius University, Lithuania2 Biomedical Physics Laboratory, Institute of Oncology, Vilnius University, Lithuania


Upconversion is a type of nonlinear process, capable of converting the lower energy excitation light into a higher energy emission. Up-converting nanoparticles (UCNPs) with unique multi-photon excitation photoluminescence properties have recently been intensively explored as novel contrast agents for biomedical imaging. By conjugating nanoparticles with biologically active or cancer targeting molecules the targeted anticancer drug delivery and cell imaging with UCNPs was demonstrated. This non-covalent drug loading strategy can also be used to load photosensitizer molecules on UCNPs for potential near-infrared light induced photodynamic therapy. The near-infrared excitation wavelengths of these particles offer additional advantages such as deep tissue penetration and low photodamage to biological samples. UCNPs have shown their potential as therapeutic agents, acting as nanotransducers for PDT and delivery vehicles for drugs and genes. To develop UCN-based PDT as a clinical cancer treatment modality, systematic evaluations of PDT efficacy, especially parameters such as the photosensitizer-UCNs ratio, the tumour-targeting specificity and the optimal light dose, should be achieved. Additionally, in vivo penetration depth studies are required to provide a more realistic assessment concerning the feasibility of UCN-based PDT in treating deep tumours. Our preliminary results suggest UCNPs as promising nanocarriers for multi-functional cancer therapy and imaging.


Spectrometry and Reflectometry of Biological Tissues for Diagnostic Purposes

S. Bagdonas



Probing Molecules on Different Length Scales – From Environmental Monitoring to Biophotonics

S. Svanberg



Photometric Nanolabels for Biosensors and Bioassays

M. MakDepartment of Physics, Chemistry and Biology, Linkoping University, Linkoping, Sweden


People are concerned about public health and thousands of new diagnostic tests are being introduced each year. The success of those diagnostic tests mainly relies on the ability to achieve high sensitivity and therefore the need for highly sensitive biolabel systems are of increasing importance.Over the years, there are intensive researches on synthetic nanoparticles, both organic and inorganic, as optical biolabel systems. We will present the applications and prospective on nanoparticles to achieve the goals on lowering of detection limits, multiplexing detection, signal amplification, and prevention of photobleaching effects. We will also present our development on novel class of biolabels, which are hyper-dense nanometer-sized organic crystals, can be triggered by chemical induction, instantly releasing huge amount of signal-generating molecules creating a so-called “SuperNova Effect” (a single nanocrystal biolabel with a dimension of 100 nm contains around 106 signal molecules) to achieve signal amplification. The organic nanocrystal biolabel combines the advantages of signal amplifications (similar to conventional enzyme labels), and high stability which holds promise for the development ultrasensitive bioassay.


Use of TiO2 Photoluminescence for Salmonella Detection

R. ViterOdessa National I. I.Mechnikov University, Odessa, Ukraine


TiO2 is well known material, which was used for different applications [1]. Quantum confinement effects in nanostructured TiO2 resulted in band gap increase, enhance of photo catalytic activity and room temperature photoluminescence (PL) [2]. It was reported on room temperature PL in TiO2 nanostructures [2]. It was found that TiO2 nanostructures demonstrated emission in the range 430–560 nm [2]. Two mechanisms of luminescence were proposed: self trapped excitons (STE) (430-510 nm) and oxygen vacancies (530–560 nm) [2]. TiO2 has low Isoelectric Point pH = 5.5 what makes some advantages to protein immobilization on its surface [3]. Having this properties TiO2 was used as in biosensors, mostly electrochemical [1]. The recent study of PL in TiO2 point to significant interest to this material and prospect use of TiO2 PL in different applications, like sensors and biosensors [4]. Food safety and agriculture are important fields of human activities. The quality control of food and agriculture production will decrease the risks of human diseases, caused by toxin infections. Salmonella is one of the mostly monitored pathogens in EU. Optical biosensors were developed for salmonella detection at concentrations down to 102–105 cfu/ml, based on Surface Plasmon Resonance (SPR) and reflectance spectroscopy.In our previous papers we have shown the use of PL of nanostructures for biosensor application [5, 6]. In the present work we report the characterization of TiO2 nanoparticles for application in optical immune biosensor for salmonella detection.

References

[1] E. Comini, et. al, Quasi-one dimensional metal oxide semiconductors: Preparation, characterization and application as chemical sensors, Progress in Materials Science, 54, 1–67, (2009)

[2] Xiaodong Li et al., TiO2 films with rich bulk oxygen vacancies prepared by electrospinning for dye-sensitized solar cells, Journal of Power Sources, 214, 244–250, (2012)

[3] P. Si, et al., Hierarchically structured one-dimensional TiO2 for protein immobilization, direct electrochemistry, and mediator-free glucose sensing, ACS Nano; 5(9), 7617–7626, (2011)

[4] Jana Drbohlavova et al., Effect of Nucleic Acid and Albumin on Luminescence Properties of Deposited TiO2 Quantum Dots, Int. J. Electrochem. Sci., 7, 1424–1432, (2012)

[5] R. Viter et al., Immune biosensor based on Silica Nanotube Hydrohels for rapid Biochemical Diagnostics of Bovine Retroviral Leukemia, Proceedia Engineering, 25, 948–951, (2011)

[6] Roman Viter, et al., ZnO Nanorods Room Temperature Photoluminescence Biosensors For Salmonella Detection // Technical Digest Frontiers in Optics (FiO) 2012 and Laser Science (LS) XXVIII Meetings. (Optical Society of America, Washington, DC, 2012), FW3A.61, (2012)


Confocal Fluorescence Spectroscopy for Bio-sensor Applications and Potentialities

S. Balme, J.-M. Janot Institut Européen des Membranes, UMR 5635, CNRS-ENSCM – Université Montpellier 2 Département Interface,

Physico-chimie, Polymère – Université Montpellier 2 CC047 Montpellier E-mail: [email protected]

Fluorescence technics are commonly used in many science areas such as chemistry or biology. In the specific area of biosensing fluorescence spectroscopy is one of methods to characterize ligand/protein interaction.1, 2 In most of case, only the properties of fluorescence emission or quenching have been used. The techniques of time resolved fluorescence and polarization of fluorescence permit at weak concentration to obtain information both the direct environment and the movement of a fluorescent molecule.3 Since 25 years the emergence of confocal fluorescence microscopy4 has permitted many advances in biology and medicine.5 To make short, the confocal fluorescence techniques make possible the visualization of a volume of the order of the femtolitre and perfectly localised. Most recently, the development of Flurescence Liftetime imagin which combine fluorescence lifetime measurement and confocal microscopy6 open new ways for more sentive bio-sensor.7, 8 The objective of this conference will be presenting the application of confocal fluorescence spectroscopy in the area of bio-sensing. At first, the different technics based on fluorescence spectroscopy will be presented such as FRET, FRAP, time resolved fluorescence, anisotropy etc. Secondly the confocal fluorescence microscopy and spectroscopy will be discussed. Finally we will show different applications, potentialities and limits of confocal fluorescence spectroscopy.

References

[1] R. Hovius, et al., Trends Pharmacol Sci, 2000, 21, 266–273.[2] S. Balme, et al., J Photoch Photobio A, 2006, 184, 204–211.[3] S. Balme, et al., Soft Matter, 2013, 9, 3188–3196.[4] M. Minsky, Scanning, 1988, 10, 128–138.[5] W. B. Amos, et al., Biol Cell, 2003, 95, 335–342.[6] S. Balme, et al., J Membrane Sci, 2006, 284, 198–204.[7] P. Blandin, et al., Confocal, Multiphoton, and Nonlinear Microscopic Imaging III, 2007, 6630, B6300–

B6300.[8] X. F. Wang, et al., Crit Rev Anal Chem, 1992, 23, 369–395.


Application of Zinc Oxide for Optical Biosensing Technologies

V. KhranovskyyDepartment of Physics, Chemistry and Biology (IFM), Linkoping University, Linkoping, Sweden


A biosensor is an integrated miniaturized device that has a biosensitive layer, connected to transducing system for signal detection. Biocompatible layer is formed by immobilization of biological recognition element (antibody, enzyme, DNA probe, receptor protein, nucleic acid or the whole cell) on the surface of the transducer (Fig. 1) [1]. Transducer system may be electrochemical, piezoelectric, thermometric, magnetic or optical. Among optical biosensors SPR based technique is the most popular, being highly sensitive and selective method. However, such systems are complex and require considerable time, expense and expertise to develop.Alternative is the photoluminescence (PL) biosensors – where the photo-lumi nescence from some nano-structured material (usually semi-conductor) is used for the detection of changes in the properties of nano-bio interface. PL biosensor detects the change of PL signal before and after immobilization of biological substances on the nanostructured surface of the sample and after application of analyte. Performance of PL biosensor is until large extent determined by the light emitting properties of the transducer material. This motivates using of novel semiconductor materials with advanced PL properties as transducers. Recently, interest has been focused towards applications of ZnO in biosensors due to its excellent PL properties (wide band gap (~3.3 eV) and high exciton bound energy (~60 meV) as well as high isoelectric point (IEP) of ~9.5, biocompatibility and abundance in nature. The high isoelectric point of ZnO results in a unique ability to immobilize an enzyme with a low isoelectric point through electrostatic interaction, thus, designing the effective biosensitive layer. Furthermore, nontoxicity, high chemical stability and high electron transfer capability make ZnO a promising material for immobilization of biomolecules without an electron mediator [2]. I will review the recent reports about applications of different ZnO nano structures – nanorods, nano wires or quantum dots, as a transducer for PL biosensors for detection glucose, dopamine, DNA or even cancer cells. The effect of ZnO stoichiometry, structure, morphology and surface area on the properties of immobili zed biosensitive layer and sub sequently on the performance of the designed PL biosensors will be discussed. Eventually, the outline of novel trends in ZnO biosensing platform will be presented.

References

[1] P. R. Solanki et al. Nanostructured metal oxide-based biosensors, NPG Asia Mater 3 (2011) 17–24. [2] R. Yakimova, V. Khranovskyy et al. ZnO materials and surface tailoring for biosensing, Frontiers in

bioscience (Elite edition) 4 (2012) 254–278.

Fig. 1. Schematic structure of a biosensor


Optical Immune Biosensors Based on the SPR and TIRE: Problems and Perspectives of their Practical Application

at the Registration of Some Biochemical Parameters

N. F. Starodub National University of Life and Environmental Sciences of Ukraine, Kiev, Ukraine


Direct control of biospecific interactions is very important for solving a number of practical tasks. The optical technique, in particular based on the surface plasmon resonance (SPR) phenomenon, is the most promising. The attenuated-total-reflectance method proposed in 1973 was realized for the biosensors in 1983 and now is widely used. The other optical approach for the biosensor creation is based on the total internal reflection ellipsometry (TIRE). It found wide application too. Both methods give possibility to monitor the association and dissociation of a wide range of bimolecular complexes in real time without application of any labels. The usage of gold layer as a transducer in the optical biosensors is very perspective since it allows obtaining stable and reproducible signal. Acceptable performance of the biosensors requires overcoming some existed problems. Some proteins are difficult to attach directly to a metal surface and other ones may be exposed to denaturation at the direct adsorbtion on such surface. Number of physically adsorbed molecules is limited by surface area of the transducer, which is amenable to optical registration. This limitation can be prevented by compounds that can form on the surface as branched structures. Thus, it is possible to further increase the sensitivity of the immune biosensor. From other side the binding centers of the immobilized molecules should be maximal exposed toward solution. All these aspects as that connected with the algorithm of the analysis, its simplicity, cost, rapidity, possibility to be fulfilled on line regime and in field conditions by the mentioned biosensors are as main purpose of this report. Some mycotoxins (T2-mycotoxin, patulin, aflatoxin and searelenone), anti-insulin and anti-retroviral antibodies as well as salmonella are as model objects the determination of which are very needed for practice in field of modern diagnostics, environmental monitoring and food quality control. In results of investigations it was stated that the more effective way for the immobilization of high molecular weight antigens or hapten-conjugates is the formation of the polyelectrolyte layer on the transducer surface and additional creation of intermediate one from Staphylococcus aureus protein A. In case of the determination of some substances with high molecular weight the most appropriate is the “direct” way of analysis. At the control level of mycotoxins, pesticides and other low molecular weight substances it should be used so called “competitive” or “to saturated” ways, as a rule, and for SPR based immune biosensors, especially. The last type of biosensors may be applied for screening mycotoxins among of environmental objects and foods and for both procedures as screening above mentioned antibodies and verification of their analysis fulfilled by other methods. Regarding immune biosensor based on the TIRE, it is able not for screening both types of substances only, but also for confirming or verification of the results obtained by other methods. Unfortunately, both types of immune biosensors without additional methods cannot provide the practical requirements for the estimation of Salmonella contamination of the products. The cost and simplicity of analysis fulfilled by both biosensors is not yet appropriate for practice. That’s why there is necessary to search new approaches, including the use of nanostructured materials, nanoparticles and nanotubes for creation of biosensors according modern demands of practice.

33ORAL PRESENTATIONS

ORAL PRESENTATIONS

Fabrication and Characterization of a 3-D Non-Homogeneous Tissue

like Mouse Phantom for Optical Imaging

S. Avtzi, A. Zacharopoulos, G. ZacharakisInstitute of Electronic Structure and Laser, Foundation for Research and Technology Hellas,

Heraklion, Crete, GreeceE-mail: [email protected]

Modeling of light transport in tissue not only requires the development of new theoretical models and experimental procedures, but also the construction of realistic tissue-simulating phantoms. The goal of this study is to develop a three-dimensional (3D), non-homogeneous phantom that matches the geometry and optical characteristics of the mouse head in the visible and near infrared spectral range. The fabrication of the phantoms consists of three stages. In the first stage initial prototypes of the mouse brain, skull and skin are designed based on realistic mouse head atlases [1] and are manufactured by using accurate 3D printing, allowing complex objects to be built layer by layer. During the second stage the fabrication of molds is performed by embedding the prototypes into a silicone-latex mixture. In the final stage the detailed phantom is constructed by loading the molds with polyester resin [2]. The optical properties of the phantom are controlled by using appropriate quantities of India ink and polystyrene microparticles. The final phantom consists of 3 layers, each one with different absorption and scattering coefficient (μa, μs) to simulate the region of the mouse brain, skull and skin (for typical values see Ref. 3). The anatomical structures are based on a digital phantom which is composed by reconstructing images, obtained from slices of a mouse head cryosection block. This technique allows us to produce a highly detailed phantom, with accurately predictable optical properties. This new phantom will enable the optimization of an optical tomographic system developed in our laboratory, for high resolution 3D molecular imaging of the mouse brain.

Acknowledgements

This work is supported by the Grants “Skin-DOCTor” and “Neureka!” implemented under the “ARISTEIA” and “Supporting Postdoctoral Researchers” Actions respectively, of the “OPERATIONAL PROGRAMME EDUCATION AND LIFELONG LEARNING”, co-funded by the European Social Fund (ESF) and National Resources.

References

[1] B. Dogdas, et al., Digimouse: A 3D Whole Body Mouse Atlas from CT and Cryosection Data, Phys. Med. Bio, 52: 577–587, 2007.

[2] Fatma-Zohra Bioud et al., “Fabrication and characterization of optical phantoms”, Proc. SPIE 7099, Photonics North 2008, 709906 (2008).

[3] A. Zacharopoulos et al, “Development of in-vivo fluorescence imaging with the Matrix-Free method”, J. Phys.: Conf. Ser. 255 012006 (2010).

34 ORAL PRESENTATIONS

Modelling the Appearance of Chromatic Environment Using Hyperspectral Imaging

S. Fomins1, M. Ozolinsh1, 2 1 Institute of Solid State Physics, Riga, Latvia

2 Optometry and Vision Science Dept. University of Latvia, Riga, LatviaE-mail: [email protected]

Color of objects is a spectral composition of incident light source, reflection properties of the object itself, and spectral tuning of the eye. Light sources with different spectral characteristics can produce metameric representation of color; however most variable in this regard is vision. Pigments of color vision are continuously bleached by different stimuli and optical density of the pigment is changed, while continuous conditions provide an adaptation and perception of white. Special cases are color vision deficiencies which cover almost 8 % of male population in Europe. Hyperspectral imaging allows obtaining the spectra of the environment and modelling the performance of the dichromatic, anomalous trichromatic, as also normal trichromatic adapted behaviour. First, CRI Nuance hyperspectral imaging system was spectrally calibrated for natural continuous spectral illumination of high color rendering index and narrow band fluorescent light sources. Full-scale images of color deficiency tests were acquired in the range of 420 to 720 nm to evaluate the modelling capacity for dichromatic vision. Hyperspectral images were turned to cone excitation images according to Stockman & Sharpe (2000) [1]. Further, model was extended for anomalous trichromacy conditions. Cone sensitivity spectra were shifted by 2 nm according to each anomaly type. SWS cone signals were balanced in each condition to provide the latent object appearance and background fading. Automatic scaling was provided for short wave cone signals, while anomalous long wavelength sensitive or middle wavelength sensitive cones signals maintained constant. Model performance was compared to responses of carriers of anomalous vision. Third, models of colour adaptation were incorporated to account for adaptation processes in vision. CMCCAT2000 transform was applied to predict the appearance of the chromatic media in illumination of different correlated color temperature.

Acknowledgement

The research is supported by the ERAF project No 2010/0259/2DP/2.1.1.1.0/10/APIA/VIAA/137.

References

[1] Stockman et al., Spectral sensitivities of the middle- and long-wavelength sensitive cones derived from measurements in observers of known genotype, Vision Research, 40, 1711–1737 (2000).


Wide-bandwidth Photon Time of Flight Spectroscopy for Biomedical and Pharmaceutical Applications

D. Khoptyar1, A. A. Subash1, M. Saleem2, O. H. A. Nielsen3, S. Andersson-Engels1

1 Lund University, Sweden2 National Institute of Lasers and Optronics, Pakistan

3 Technical University of Denmark, DenmarkE-mail: [email protected]

Diffuse optical spectroscopy (DOS) is an important component of biophotonics toolbox that readily finds its applications in biomedical optics. Furthermore DOS is also is highly actual in numerous applications within pharmaceutical, food, wood and agrichemical industries. This covers new product R&D, fabrication process monitoring and quality control. The further advance in applications urges development of the novel DOS instrumentation capable to deliver highly accurate and exhaustive spectroscopic data at high speeds relevant for such time-critical application as real-time treatment response monitoring or in-line process control.Recent advance in photonics technologies enables development of the new highly precise and elaborated spectroscopic techniques which are free from limitations adherent to CW DOS. Therein it is becoming possible to independently determine absorption and scattering of spectra of virtually any heterogeneous material. This eventually leads to increased accuracy and diminishing price for evaluation of chemical composition and physical properties of the sample. In present contribution we present state of the art performance characteristics of the novel broad-band photon time of flight (PTOF) spectrometer for analysis of turbid media. The instrument is based on the broad band supercontinuum source. We discuss performance of the instrument in number of prospective applications and review newly developed methods for calibration and verification performance of the instrument. In order to test ability of the present setup for pharmaceutical analysis we evaluated absorption and scattering spectra of test tablets set prepared from ibuprofen (used as a drug) and mannitol (used as a filler) mixed in different proportions. Absorption and scattering spectra of tablets compressed from pure ingredients were also measured. Analysis of the recorded spectra shows that absorption spectra of all mixed tablets can be highly accurately fitted with linear combination of absorption spectra of the ingredients. This enables us accurately evaluate drug concentration in a tablets with an average accuracy of 1.2% without using any type of chemometric calibrations [1]. This experiment shows clear advantage of PTOF technique over CW light extinction techniques widely applied at industry to date. Aside of demonstration the superiority of PTOF technique the result also enables to verify linearity and performance of the present setup. Indeed as absorption spectra of ingredients and multicomponent tablets were taken at highly different scattering levels the high absorption fit quality suggest that the present setup and data evaluation algorithms are free from non-linear distortions and enable precise evaluation of absorption and reduced scattering coefficient of turbid samples in a wide dynamic range.

References

[1] D. Khoptyar et al., “Broadband photon time-of-flight spectroscopy of pharmaceuticals and highly scattering plastics in the VIS and close NIR spectral ranges” Optics Express to be submitted.


Application of Principal Component Analysis to Multispectral Imaging Data for Evaluation

of Pigmented Skin Lesions

D. Jakovels, I. Lihacova, I. Kuzmina, J. SpigulisBiophotonics Laboratory, Institute of Atomic Physics and Spectroscopy,

University of Latvia, Riga, LatviaE-mail: [email protected]

Non-invasive and fast primary diagnostics of pigmented skin lesions is required due to frequent incidence of skin cancer – melanoma [1].Multispectral imaging (MSI) is a noncontact optical technique and has shown promising potential for in vivo diagnostics of skin lesions [2–4]. Different data processing algorithms of multi-spectral image cubes are used – extraction of morphological and reflection related parameters [2], regression analysis for assessment of skin chromophores [3] or combining different spectral channels [4].Principal component analysis (PCA) is an alternative tool for assessment of skin chromophores [5]. PCA is a statistical tool for linear transformation of imaging data into an orthogonal coordinate system, where the axis corresponds to the inherent information within the data set. The advantage of PCA is its speed of computation allowing near real-time analysis of large multi-spectral image cubes.The aim of this work is to demonstrate the applicability of PCA to MSI data for evaluation of pigmented skin lesions. Clinical measurement results of melanomas and benign nevi will be presented. Our previous study showed that main difference between two lesions could be found by looking at maps of first two principal components (PC1, PC2) as they capture the most variability in the data. PC1 could be used for separation of pigmented lesions form normal skin, but PC2 could be used for further classification of skin lesions into benign and suspicious. Such MSI method and algorithm based on PCA will be presented and discussed.

References

[1] W. Klaus and J. R. Allen, “Fitzpatrick’s Color Atlas & Synopsis of Clinical Dermatology,” McGraw-Hill Professional, New York (2009).

[2] S. Tomatis, et al., “Automated melanoma detection with a novel multispectral imaging system: results of a prospective study,” Phys. Med. Biol. 50, 1675–1687 (2005).

[3] I. Kuzmina, et al., “Towards non-contact skin melanoma selection by multi-spectral imaging analysis,” J. Biomed. Opt. 16(6), 060502 (2011).

[4] I. Diebele, et al., “Clinical evaluation of melanomas and common nevi by spectral imaging,” Biomed. Opt. Express 3(3), 467–472 (2012).

[5] J. M. Kainerstorfer, et al., “Principal component model of multispectral data for near real-time skin chromophore mapping,” J. Biomed. Opt. 15(4), 046007 (2010).


Assessment of Hemoglobin Dynamics in Traumatic Bruises Using Temperature Depth Profiling

L. Vidovic, M. Milanic, B. MajaronJozef Stefan Institute, Ljubljana, Slovenia


Perceived color of traumatic bruise depends strongly on depth of the spilled blood, natural skin tone, ambient light conditions, etc., which prevents an accurate and reliable determination of the time of the injury [1]. Techniques such as diffuse reflectance spectroscopy was applied for objective characterization of bruises [2]. A simple model of mass diffusion and biochemical transformation kinetics was introduced. However, the parameters of the model were not determined directly. Instead, biologically plausable values were assumed in the preliminary analysis.Pulsed photothermal radiometry (PPTR) allows noninvasive determination of the laser-induced temperature depth profile in strongly scattering biological tissues including human skin [3]. We have applied this technique to characterize dynamics of extravasated hemoglobin. A 1 ms laser pulse at 532 nm is absorbed well by the epidermal melanin and hemoglobin in the dermis (see Fig 1). Dynamics of hemoglobin concentration profile evolution, Nh, was calculated according to the earlier assumed analytical model. By applying Monte Carlo simulation of laser energy deposition a more rigorous comparison with measured temperature profiles is possible.We show that PPTR depth profiling can be used to derive rather accurate estimate of the hemoglobin mass diffusivity, hemoglobin degradation time, as well as approximate skin geometry. This enables assessment of the bruise healing dynamics and could offer a valuable addition to existing bruise age determination techniques.

0.0 0.2 0.4 0.6 0.80

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Fig. 1. Laser-induced temperature depth profiles (solid) in a bruise on the forearm of a 55 year old female volunteer 14 hours (a), 38 hours (b), and 110 hours (c) after injury. Dashed lines indicate

depth profile of hemoglobin concentration, Nh. Vertical line indicates epidermal-dermal junction impenetrable for hemoglobin.

References

[1] N. E. I. Langlois, “The science behind the quest to determine the age of bruises—a review of the English language literature,” Forensic Sci Med Patho, vol. 3, pp. 241 (2007)

[2] L. L. Randeberg et al., “A novel approach to age determination of traumatic injuries by reflectance spectroscopy,” Lasers Surg Med, vol. 38, pp. 277 (2006).

[3] M. Milanič et al., “A spectrally composite reconstruction approach for improved resolution of pulsed photothermal temperature profiling in water-based samples,” Phys Med Biol, vol. 54, p. 2829 (2009)


Accumulation of Photoluminescent MES-Capped Gold Nanoparticles in MiaPaCa-2 Cancer Cells

M. Matulionyte1, 2, R. Marcinonyte1, R. Rotomskis1, 2

1 Institute of Oncology, Vilnius University, Vilnius, Lithuania2 Faculty of Physics, Vilnius University, Vilnius, Lithuania


Gold-based nanomaterials have received considerable attention for biomedical applications especially after recent advances in nanotechnology that have given rise to photoluminescent gold and silver nanoclusters. Composed of a few to a hundred atoms, they exhibit molecule-like properties including discrete electronic states and size-dependent photoluminescence. Due to chemical stability, easy surface modification and excellent photostability photoluminescent gold nanoparticles (NP) are very promising fluorescent labels for biological application. Despite great interest in application of gold NP in biomedicine, there are only several research papers published on intracellular accumulation and cytotoxicity of ultra small (<2 nm) photoluminescent gold NP.In this work accumulation of photoluminescent 2-(N-morpholino) ethanesulfonic acid (MES)-stabilized gold nanoparticles in Mia PaCa-2 cancer cells and their effect on cell viability was investigated.Photoluminescent MES-capped gold NP were synthesized using modified synthesis proposed by Bao et al. [1]. 1 ml of 0.29 M chlorauric acid was mixed with 5 ml of 1 M MES buffer solution (pH 6.3) and left under vigorous stirring for 21.5 hours at 37°C. Synthesized NP exhibited photoluminescence in blue spectral region at 476 nm wavelength.Dynamics of accumulation of MES-capped gold NP in MiaPaCa-2 cancer cells were investigated treating cells with 45.4 mg/mL and 22.7 mg/mL of gold-MES NP. Confocal microscopy images were taken after 3, 6, 9 and 24 hours of incubation. After 3 hours of incubation with higher concentration of gold-MES NP the adherence to the cell membrane and localization of granulated clusters at the perinuclear region were observed. Diffuse distribution (including cell nucleus) of gold-MES NP was visualized after 6, 9 and 24 hours of incubation. In case of incubation with lower concentration of gold-MES NP the process of accumulation was slower and the adherence to the cell membrane and formation of granulated clusters were observed after 6 and 9 hours of incubation. After 24 hours of incubation diffuse distribution of gold-MES NP was observed inside the cells but the photoluminescence intensity was lower than in case of incubation with higher concentration of gold-MES NP showing that less gold nanoparticles accumulated in the cells.Our study results revealed that photoluminescent gold-MES NP accumulate in MiaPaCa-2 cancer cells and overcome the nuclear membrane barrier. The diffuse distribution within the cells was observed. However, it was shown that both concentrations of gold-MES NP affect the viability of MiaPaCa-2 cancer cells.

References

[1] Y. Bao et al., Formation and Stabilization of Fluorescent Gold nanoclusters Using Small Molecules, J. Phys. Chem., 114, 15879–15882 (2010).


Determination of the Maximal Safe Laser Radiant Exposure for Human Skin Using Pulsed Photothermal Radiometry

B. Majaron1, L. Vidovic1, M. Milanic1, W. Jia2, J. S. Nelson2

1 Jozef Stefan Institute, Ljubljana, Slovenia 2 Beckman Laser Institute and Medical Clinic, Irvine, CA, U.S.A.


The efficacy and safety of several cutaneous laser treatments are compromised by nonselective absorption of laser light in epidermal melanin. This limits the light fluence delivered to the subsurface target site (e.g., blood vessel, hair follicle, or tattoo granule) and induces a risk of permanent side effects, such as scarring or dyspigmentation, due to overheating of the epidermal basal layer. We present here a novel approach to determination of the maximal safe radiant exposure value (Hmax) for a specific pacient and irradiation site, using temperature depth profiling based on pulsed photothermal radiometry (PPTR) technique, developed and tested earlier in our group [1].PPTR measurements on 326 distinct test spots in 12 healthy volunteers were performed earlier, using 3 ms laser pulses at 755 nm and radiant exposure of 6 J/cm2 [2].From the recorded PPTR signals, the respective laser-induced temperature depth profiles in skin are reconstructed using a custom iterative algorithm with adaptive regularization [1]. Then, the epidermal damage threshold is predicted separately for each test site, using a numerical model of heat transfer and Arrhenius model of protein coagulation kinetics [3]. The predictions are compared with severity of adverse effects (crusting) observed after irradiation of the same test spots with the same laser at radiant exposures of 10–90 J/cm2 with application of cryogen spray precooling.Maximal safe radiant exposure value (Hmax) for any skin site can then be obtained by taking the respective PPTR-determined temperature profile and ramping up the radiant exposure in the numerical model until a predefined value of the coagulation parameter (Ω) is reached anywhere within the epidermis. We find that all test spots that had received irradiations below the individually predicted Hmax value developed none or negligible injury. The described approach allows a rather accurate prediction of maximal safe radiant exposure across a wide range of skin phototypes, and might enable increased efficacy and safety of several cutaneous laser treatments, such as treatment of vascular lesions, removal of unwanted hair, etc.

References

[1] M. Milanič et al., A spectrally composite reconstruction approach for improved resolution of pulsed photothermal temperature profiling in water-based samples, Phys. Med. Biol., 54, 2829–2844 (2009)

[2] W. Verkruysse et al., Infrared measurement of human skin temperature to predict the individual maximum safe radiant exposure, Lasers Surg. Med. 39, 757–766 (2007)

[3] M. Milanič et al., Numerical optimization of sequential cryogen spray cooling and laser irradiation for improved therapy of port wine stain, Lasers Surg. Med., 43, 164–175 (2011)


Detection of Phase Transition of Adipose Tissue by Spectral OCT Refractive-Index Measurement

I. Yu. Yanina1, N. A. Trunina1, V. V. Tuchin1, 2, 3 1 Saratov State University, Saratov, Russia

2 Institute of Precise Mechanics and Control RAS, Saratov, Russia3 University of Oulu, Oulu, Finland


One of the urgent problems of biophotonics is monitoring of adipose tissue conditions in order to provide selective and noninvasive or minimally invasive fat reduction.1 One of the effective fat reduction technology is hyperthermia.2 Recently a number of such technologies was developed that based on well-controlled tissue temperature in time and volumetric laser heating of tissues and organs.3–5 Adipose tissue is characterized by relatively low-temperature melting point that can significantly affect the heating kinetics of tissue with fat accumulation. At the heating temperature from 24°C to 45°C lipid components of adipose tissue undergo several phase transitions in a fairly wide temperature range, which is associated with a multicomponent lipid content of the fat cells.6 Optical coherence tomography (OCT) measurements of temperature dependent index of refraction of lipid containing tissue components can be suggested as a useful tool for detection of phase transitions in fat cell structures.7, 8

The goal of the present work is to determine phase transition kinetic curve of the subcutaneous fat by measuring the refractive index using spectral OCT system. Fat tissue slices having the thickness 200–300 μm were used in the in vitro experiments. Each sample of area 0.5 × 0.5 cm2 was separated by spacers into 4 zones. Each sampling zone was about 0.3 cm in diameter. The first zone was used as a control and this fat site has not been under any treatment (no stain, no radiation). The second zone was treated with dye. Water-ethanol solutions of indocyanine green (ICG) and brilliant green (BG) with the concentration 1 mg/ml and 6 mg/ml, respectively, were used for fat tissue staining. The third zone was irradiated by light. The CW laser diode (VD–VII DPSS, 808 nm) and the dental diode lamp (Ultra Lume Led 5, 442 and 597 nm) were used for irradiation of tissue slices. The exposure time was 1.5 min with the laser and 15 min with the diode lamp. The zone 4 was stained with a dye first, and then irradiated with a light source. The observations were conducted for four zones simultaneously. Fat tissue slices were stacked and sandwiched between two glass plates having a spacer. The prepared sample was placed in temperature-stabilizing system (heated sample-holder connected to the thermostat TJ-TC-01). We have demonstrated the method for detection of phase transition of adipose tissue by precise refractive index measurement with the spectral OCT. In our measurements, abrupt change in both refractive index and optical transmission were found in the temperature range of 37°C to 42°C, which is in a good agreement with the temperature range for the gel-to-liquid phase transition of the artificial (liposomal) membrane (DPPC).9 In practice, this heating, which is additional to photodynamic treatment (PDT), can be done by the same laser and photosensitizer that used for PDT. Indeed, laser (LED) energetic properties and dye concentration should be optimized. The proposed method can be useful in practice to accompany laser technologies for subcutaneous fat reduction.

References

[1] V. V. Tuchin, et al., Destructive fat tissue engineering using photodynamic and selective photo-thermal effects, Proc. SPIE 7179, 71790C-11 (2009)


Effect of Biological Environment on Luminescence of ZnCdS Nanoparticles

E. K. Volkova1, V. I. Kochubey1, J. G. Konyukhova2, A. A. Skaptsov1

1 Saratov State University, Saratov, Russia2 Institute of Mechanics and Physics, Saratov State University, Saratov, Russia


The reason for increased use of semiconductor nanoparticles in various fields of biology and medicine is the fact that semiconductor nanoparticles are now competing in photostability and quantum yield of luminescence with well-studied molecular fluorophores. One of the most important properties of semiconductor nanoparticles is fluorescence because of its high sensitivity to the environment of the particle providing the sensitivity of a sensor.A study of the luminescence peak position for ZnCdS nanoparticles placed in different biological media (muscle tissue of chicken, muscle tissue fluid of chicken, rat blood plasma stabilized with sodium citrate, egg albumin, hair keratin, glucose solution) is carried out.ZnCdS nanoparticles with average size of 10 nm were synthesized from a mixture of aqueous solutions of cadmium chloride (CdCl2) and zinc chloride (ZnCl2) by addition of sodium sulphide solution (Na2S) at room temperature. The nanoparticles were not stabilized because, to achieve high sensitivity of such particles, it is requires a significant amount of surface defects non-stabilized by coating with a layer of a stabilizer.It is shown that the luminescence peak position for the ZnCdS nanoparticles is sensitive to the nanoparticle environment. It is our assumption that shift of the luminescence peak of ZnCdS nanoparticles is due to particle sensitivity to the presence of Ca2+ ions (Table 1).

Table 1. Dependence of the luminescence peak position for the ZnCdS nanoparticles on the type of their environment.

Medium Luminescence peak position (nm)

Water 625

Muscle tissue fluid of chicken 658

Chicken muscle tissue 654

Chicken muscle tissue (washed) 649

Rat blood plasma 658

CaCl2 solution 649

The maximum shift of the luminescence band of the nanoparticles is observed in interstitial fluid, and the smallest is in the muscle tissue washed from liquid. The presence of the shift for muscle tissue can be explained by residual concentration of calcium ions originating from the intracellular fluid. As a result, the luminescence spectrum consists of two bands, shifted and unshifted, and the peak position depends on the ratio of the amplitudes of the bands. For albumin, keratin and glucose, shift is absent, which indirectly confirms the effect of calcium on the band position.It can be concluded that the position of the luminescence band of ZnCdS nanoparticles depends strongly on the composition of a biological object into which they are placed.


Fluorescence Spectroscopy of Gastrointestinal Tumours – In Vitro Studies and In Vivo Clinical Applications

L. Angelova1, E. Borisova1, Al. Zhelyazkova1, M. Keremedchiev2, B. Vladimirov2

1 Institute of Electronics, Bulgarian Academy of Sciences, Sofia, Bulgaria2 University hospital “Queen Giovanna-ISUL”, Sofia, Bulgaria


Tumors of the gastrointestinal tract (GIT) are at first places of newly developed cancers every year. According to the Bulgarian National Cancer Registry, there are 16 490 registered colon cancer cases in Bulgaria, or 6.3% of all cancer cases for the period [1].The main optical methods, applied in gastroenterology include fluorescence, diffuse reflectance, Raman and near-infrared spectroscopy, optical coherence tomography, and confocal laser-scanning microscopy. These techniques make a connection between biochemical and morphologic properties of tissues and individual patient care.Investigations presented are based on in vitro fluorescence measurements of excitation-emission matrices for GIT neoplasia and in vivo measurements in the frames of initial clinical trial for tumor fluorescence spectra detection, applied for introduction of spectroscopic diagnostic system for optical biopsy of GIT tumors in the daily clinical practice of University Hospital “Queen Giovanna-ISUL”, Sofia. Autofluorescence and exogenous fluorescence signals are detected from normal mucosa, inflammation, dysplasia and carcinoma and main spectral features are evaluated.For in vitro cancer fluorescence spectroscopy measurements the FluoroLog 3 system (HORIBA Jobin Yvon, France) is used. It consists of Xe lamp (200–650 nm), scanning double monochromators, and PMT detector with high performance in the region 200–800 nm.For in vivo fluorescence measurements of gastrointestinal pathologies excitation sources at 405, 530 and 630 nm are applied. As exogenous fluorescent marker 5-ALA/PpIX is used. It is orally applied, as a water solution (20 mg/kg dose), 6 hours before measurement.When normal tissue is excited in the end of UV and blue spectral range, autofluorescence spectrum consists mainly from of collagen, elastin, protein cross-links, NADH and flavins fluorescence signals. The increase in the red/green fluorescence ratio is told to be one of the main predictors of dysplasia and malignancy. Improvement of diagnostic accuracy could be reached with application of exogenous contrast fluorophores, such as PpIX. However, false-positive results, related to accumulation of 5-ALA/PpIX in inflammatory areas of the GIT are observed. Low specificity could be overcome, when dimensionless ratios of the fluorescent maxima are used for differentiation and the autofluorescence background could be reduced, when I or II maxima of the PpIX absorption in green-yellow spectral regions are applied.Our investigations reveal very high sensitivity of fluorescence technique for early GIT neoplasia detection and differentiation from dysplastic and inflammatory lesions. In our clinical practice we tried few techniques for improvement of the contrast between normal and abnormal tissues sites, related to increase of the specificity of tumour diagnosis, which will be discussed in our poster report.

References [1] Bulgarian National Cancer Registry, Volume XXI, 2012

Acknowledgements

This work is supported by the National Science Fund of Bulgarian Ministry of Education, Youth and Science under grant #DMU-03-46/2011


Study of Blood Flow Behaviour in Microfluidics Device Using Spectral and Time Domain Optical Coherence Tomography

D. Bukowska, M. Szkulmowski, M. WojtkowskiInstitute of Physics, Faculty of Physics, Astronomy and Informatics,

Nicolaus Copernicus University, Torun, PolandE-mail: [email protected]

Although Optical Coherence Tomography is mostly used for imaging of tissue morphology it is also capable of visualizing functional process in biological tissues. In particular, there has been a considerable interest in ocular blood flow assessment. Changes of retinal blood circulation are considered to be a condition associated with a number of eye diseases such as age related macular degeneration, glaucoma and diabetic retinopathy. Several OCT techniques for flow detection in the eye have been introduced up to date. The most widely used include the phase resolved methods and resonant Doppler methods. Our group proposed a Spectral and Time domain OCT method which can detect the flow based on the Doppler frequency shift.Since the Doppler OCT techniques have already enabled imaging of biological flow in large vessels, the reconstruction of velocity maps of the capillary network still provides a challenge. In the flow maps of capillary network randomly varying Doppler signal is observed. There may be few hypotheses that could explain the observed effects. One possible explanation is that blood in such small vessels cannot be treated as optically homogenous medium anymore since the vessel diameter is already similar to that of individual red blood cells. Different blood constituents may flow with different, varying velocities which results in random Doppler signal. Moreover in small capillaries the hematocrit is extremely low. Under all of these conditions Doppler OCT may be inaccurate in blood flow measurements. In this paper we would like to present a microfluidic system to investigate the flow behavior of blood using Spectral and Time domain Optical Coherence Tomography. An exemplary result presents Fig. 1. The key idea is to propose novel method for in vivo measurement of rheological parameters of the blood using simple device with geometry similar to capillaries network, to get a qualitative and quantitative understanding of the nature of flow in vessels with thickness comparable to the size of a single erythrocyte.

Fig. 1. Three-dimensional imaging of blood circulation in microfluidics device with cross-section 300 µm × 40 µm; a. An example of structural OCT image from 3D data set; b. Velocity map

corresponding to the structural image; c. Three-dimensional representation of axial velocity profiles obtained from OCT data.


Change Dynamics of RBC Morphology after Injection Glucose for Diabetes by Diffraction Phase Microscope

N. A. Talaykova1, A. L. Kalyanov1, V. V. Lychagov1, V. P. Ryabukho1, 2, L. I. Malinova3

1 Saratov State University, Saratov, Russia2 Institute of Precision Mechanics and Control, Russian Academy of Sciences, Saratov, Russia

3 FGE Saratov SII cardiology RosmedtechnologiiE-mail: [email protected]

Diabetes is disease, which spread over the world. The estimated diabetes prevalence for 2010 is 285 million and is expected to affect 438 million people by 2030 [1]. Purpose of this work is investigation change dynamics of RBC morphology after injection glucose for diabetes. Diffraction phase microscope (DPM) with double lighting systems (transmission and reflection) used in this investigation. DPM is an optical microscope, in which the diffraction phase module installed in image plane (Fig. 1a) [2, 3]. Image of the object, resulting in the microscope, combined with interference picture, produced by the diffraction phase module, in the plane of the detector matrix. Light passed through diffraction grating generate diffraction orders. Only two orders passed through the spatial light modulator (SLM) and interference on detector plane. 0 diffraction order filtered SLM and is reference beam. +1 diffraction orders save full information about objects and is object beam. A light wave passing through a phase object undergoes a phase change, which is shown in the curve of the interference fringes (1a (in the inset)). Phase map turns out interference picture after Hilbert transforms [4].Investigations were done with capillary blood smears. Control sample were obtained after hunger of 12 hour. Then, the physician performed intravenous 40% glucose solution. Blood glucose level of the patient was determined after 10, 60 and 120 minutes after glucose injection. We calculated the change of optical thickness (COT) (Fig. 1b), high, volume RBC of patients with cardiovascular disease burdened diabetes. Investigation change dynamics of RBC morphology depending on the moment after injection.

Fig. 1. a) Experimental setup DPM. MO-microobjective. Image RBC shown in the inset; b) COT RBC

References

[1] IDF. Diabetes atlas, 4 edition: www.diabetesatlas.org (2009)[2] Bhaduri B. et al., Diffraction phase microscopy with white light, Opt. Lett., V. 37, N. 6, P. 1094–1906

(2012)[3] Talaykova N. A. et al., Diffraction phase microscope, SFM-2012, P. 8–10 (2012)[4] Ikeda T. et al., Hilbert phase microscopy for investigating fast dynamics in transparent systems.

Opt. Lett, Vol. 30, N. 10, P. 1165–1168 (2005)


Application of Colour Magnification Technique for Revealing Skin Microcirculation Changes

under Regional Anaesthetic Input

U. Rubins1, J. Spigulis1, A. Miscuks2

1 Institute of Atomic Physics and Spectroscopy, University of Latvia, Riga, Latvia2 Hospital of Traumatology and Orthopaedics, Riga, Latvia


The goal of current work is to reveal small skin colour pulsations caused by skin blood microcirculation which are invisible for naked eye. In this work the colour magnification technique [1] was applied for monitoring of palm skin microcirculation changes under peripheral (Plexus Brachialis with axiliary access) Regional Anaesthesia (RA) input [2, 3]. Local Anaesthetic (LA) affects the sympathetic regulation of vascular system and this leads to increasing of amplitude of blood volume pulsations in skin. During the RA procedure patient’s arm was in steady position and 20 minute video was taken. Later the video content was processed by custom developed Matlab software. The improved colour magnification algorithm performs image segmentation, spatial decomposition of video sequence, temporal filtering of video near-heartbeat frequency band (0.7–1.5 Hz) and amplification of pulsatile signal in every pixel of skin image. Finally we are able to reveal hidden subcutaneous microcirculation changes with full spatial resolution. This optical non-contact technique is quite simple and could be used for real-time monitoring of LA effect and prediction of success of RA.

Fig. 1. The screenshot of local anaesthetic input procedure in plexus brachialis (left) and image of

palm skin taken by colour magnification technique (right).

References

[1] Hao-Yu Wu et al., Eulerian Video Magnification for Revealing Subtle Changes in the World, ACM Trans. Graph. Proc. SIGGRAPH, vol. 31(4) pp. 1–8 (2012).

[2] U. Rubins, A. Miscuks, O. Rubenis, R. Erts and A. Grabovskis. The analysis of blood flow changes under local anesthetic input using non-contact technique. IEEE Xplore vol. 2, pp. 601–604, (2010).

[3] A. Miscuks. New problem solution for regional anaesthesia. PhD Thesis, University of Latvia, Riga (2011).


TiO2 Optical Sensor for Amino Acid Detection

A. Tereshchenko, R. Viter, I. Konup, V. Smyntyna, S. Geveliuk, V. Ivanitsa Odesa National I. I. Mechnikov University, Odesa, Ukraine


A novel optical sensor based on TiO2 nanoparticles for Valine (one of the twenty standard amino acids within proteins [1]) detection has been developed. In the presented work commercial TiO2 nanoparticles (Sigma Aldrich, particle size 32nm) were used as sensor template. The sensitive layer was formed by Porphyrin coating on TiO2 nanostructured surface. As a result, an amorphous layer between TiO2 nanostructure and Porphyrin was formed. Photoluminescence (PL) spectra were measured in the range of 370–900 nm before and after Porphyrin application. Porphyrin adsorption led to the decreasing of the main TiO2 peak at 510 nm and emerging of additional peak of high intensity at 700 nm. Absorption spectra (optical density vs wavelenght, measured from 300 to 800 nm) also showed great changes – adsorption edge shift and additional peaks appearing. An adsorption of amino acid resulted in decreasing of the Porphyrin’s peak and increasing of TiO2 main peak. The interaction between the sensor surface amino acid leads to formation of new complexes on the surface and results in reducing of the optical activity of Porphyrin. Sensitivity of the sensor to the different concentration of Valine was calculated. The developed sensor can determine Valine at the range of 0.04 to 0.16 mg/ml.

Reference

[1] Chawla S. et al. An electrochemical biosensor for fructosyl valine for glycosylated hemoglobin detection based on core-shell magnetic bionanoparticles modified gold electrode, Biosens Bioelectron., 26(8):3438-43, (2011)


Assessment of Conduit Artery Vasomotion Using Photoplethysmography

K. Kanders, A. Grabovskis, Z. Marcinkevics, J. I. AivarsUniversity of Latvia, Riga, LatviaE-mail: [email protected]

Blood vessels exhibit vasomotion – spontaneous oscillation of vascular tone. The phenomenon has been observed in small arterioles and capillaries such as in the skin microcirculation (1) as well as in the large conduit arteries (2). The underlying mechanisms and the physiological role, however, are still unclear. The oscillations have been shown to be generated locally from within the vascular wall in in vitro experiments. However, the presence of central mechanisms is also indicated by synchronous oscillations in contralateral arteries (3). It is proposed for vasomotion to have a role in tissue oxygenation when perfusion is compromised and therefore it might have a substantial pathophysiological importance (4). The presence of vasomotion can be demonstrated directly by continuous measurements of diameter changes in blood vessels using vital microscopy or ultrasonography, and indirectly by measuring blood-cell velocity, capillary pressure variations and laser-Doppler flow signals.As the research in this field is ongoing and the understanding of the phenomenon is still rather obscure, researchers would benefit from a low-cost and reliable investigation technique. Photoplethysmography (PPG) has been shown to be a promising technique to use in clinical measurements (5).The goal of this study was to find out whether the PPG technique could be useful in the research of vasomotion. We assessed the fluctuations in the measurements derived from a PPG signal from the posterior tibial artery and compared them to the fluctuations of the artery’s diameter. PPG signal was simultaneously measured at knee pit and ankle, approximately 40 cm apart, registering the pulse wave in the posterior tibial artery. Diameter of the artery was measured using B-mode ultrasonography. To distinguish whether the oscillation is spontaneous or generated by a systemic factor, also the measurements of electrocardiogram, blood pressure and respiration were taken. Fluctuations were analysed in the frequency domain and compared using cross-spectral analysis methods.We have shown that the pulse wave transit-time (the time the pulse wave travels between two sites on the artery) oscillates in frequencies that correspond to oscillations in the diameter, especially in the very low frequency range (<0.04 Hz). To the best of our knowledge, this is the first study to use PPG to examine vasomotion of large conduit arteries. We conclude that PPG can be successfully used to assess low frequency oscillations of the artery diameter.

References

[1] Colantuoni, A. et al. (1984) The effects of alpha- or beta-adrenergic receptor agonists and antagon-ists and calcium entry blockers on the spontaneous vasomotion. Microvasc Res. 28(2):143–58.

[2] Hayoz, D. et al. (1993) Spontaneous diameter oscillations of the radial artery in humans. American Journal of Physiology, 264(6 Pt 2).

[3] Porret, C. A. et al. (1995) Simultaneous ipsilateral and contralateral measurements of vasomotion in conduit arteries of human upper limbs. American Journal of Physiology, 269(6 Pt 2), H1852–H1858.

[4] Nilsson, H., & Aalkjær, C. (2003) Vasomotion: mechanisms and physiological importance. Molecular interventions, 3(2), 79–89.

[5] Allen, J. (2007). Photoplethysmography and its application in clinical physiological measurement. Physiological measurement, 28(3), R1–39.


Hydrogen Peroxide and Glucose Biosensor Based on Photoluminescence Quenching of ZnO Nanoparticles

D. Sodzel1, V. Khranovskyy2, E. Kolesneva1, L. Dubovskaya1, R. Yakimova2

1 Institute of Biophysics and Cell Engineering of National Academy of Sciences of Belarus, Minsk, Belarus2 Linköping University, Department of Physics, Chemistry and Biology (IFM), Linkoping, Sweden


ZnO is a wide band gap semiconductor material with a plenty of prospective properties, including UV and visible light emission for photonic applications [1]. The intensity variation of ZnO UV photoluminescence (PL) at λ = 380 nm can be proportional to the concentration of biological substances reacting with immobilized biosensitive layer on ZnO surface. Via correct choice of material for biosensitive layer and its efficient immobilization on ZnO surface, the highly selective and sensitive PL sensors can be designed [2].We have exploited the effect of PL quenching for hydrogen peroxide (H2O2) and glucose sensing. For this, commercially available ZnO nanoparticles (NPs) from Sigma Aldrich were used as UV light emitting material. The PL intensity of as-obtained ZnO NPs was observed to decrease proportionally to H2O2 concentrations in the buffer solution. The responsible mechanism for PL quenching is shown below (Fig. 1a). H2O2 molecules accept excited electrons from ZnO conduction zone preventing its inter-band recombination with holes in valent zone. Decreasing of the recombination acts results in the quenching of PL, thus the H2O2 concentration is proportional to PL intensity decrease. Via glucose oxidase (GOx) immobilization on ZnO NPs, the PL quenching based biosensors for glucose detection was designed. Glucose decomposes on GOx, creating glucolic acid and hydrogen peroxide as by-products. Peroxide enables to detect the glucose concentration in solution. The dependence of PL quenching signal on glucose concentration is shown on Fig. 1b. The demonstrated type of biosensor confirms ZnO to be used as optical transducer for glucose detection; this biosensor can have several advantages over the existing amperemetric type based biosensors for glucose detection and can have its specific niche applications.

Fig. 1. a. Mechanism of hydrogen peroxide detection by ZnO NPs Photoluminescence; b. Dependence of ZNO NPs PL Intensity on glucose concentration (line is only guide for eyes). The

inset represents spectra of PL emission of ZnO NPs at different concentration of glucose in solution.

References

[1] V. Khranovskyy et al. Investigation of ZnO as a perspective material for photonics, Physica Status Solidi A, 205, 144–149 (2008).

[2] Pratima R. Solanki et al. Nanostructured metal oxide-based biosensors, Nature Publishing Group Asia Materials 3, 17–24 (2011).


Novel Combined Fluorescence/Reflectance Spectroscopy System for Guiding Brain Tumor Resections:

Confirmation of Capability in Lab Experiments

M. MousaviLund University, Lund, Sweden


Surgical resection of glioblastoma tumors, the most common and aggressive type of malignant brain tumor, is difficult due to its similarity in appearance to surrounding brain tissue and its infiltrative growth pattern. The standard method used today for tissue discrimination during surgical resections is visual inspection and palpation. Ultrasound imaging and MR are also taken before and after surgery in order to locate the tumor and delineate the borders between malignant and healthy tissue. This information is not always sufficient for optimal surgical results. The main idea of this project is to develop a system that can assist the surgeon in distinguishing tissue types during brain tumor resection. This system is based on an optical fiber probe, enabling in vivo fluorescence and reflectance spectroscopy during surgery. The tissue discrimination in the fluorescence signals is based on both endogenous fluorescence and contrast agents, while the reflectance correlates with optical properties of the tissue. The contrast agent employed is amino-levulinic-acid-induced Protoporphyrin IX (PpIX). The amino-levulinic acid (ALA) is administered orally to the patient prior to surgery. Malignant glial tumor tissue will then build up a higher concentration of Protoporphyrin IX, providing a fluorescence peak at 635 nm following 405 nm light excitation. The light source unit used in the system developed contains five LEDs, providing four different wavelengths in the Near-UV/visible range as well as one white light-source. This light is guided to the tissue through five separate optical fibers. At the distal end of the fiber probe these five fibers surround one collection fiber. In order to detect different emission wavelengths, five photo detectors have been employed in the detection unit of the system. The light guided back to the system through the detection fiber is selected and directed towards the five different detectors (four avalanche photodiodes and one photo diode) by using dichroic mirrors. The wavelength selection is further improved by using bandpass optical filters in front of the detectors. The primary goal is obviously to provide a signal with high sensitivity and specificity for malignant tissue. It is assumed that the PpIX concentration is well correlated with the malignant transformation of the tissue. The idea for the system is thus to combine multi-wavelength diffuse reflection and fluorescence signals to obtain information related to PpIX concentration, independent on the amount of blood in the tissue. One challenge in this development is the influence of the strong ambient light in the operation room. By pulsing the light sources and employing lock-in detection this ambient light can very efficiently be suppressed in the detection. This method has in lab tests proven to detect very low PpIX fluorescence concentrations in tissue phantoms, with insignificant influence of ambient light. More elaborate tests will be conducted with this specific system to provide its full capability, before the systems will be taken into use in the ongoing clinical research program for glioblastoma tumors conducted in collaboration with Linköping University.


Application of FLIM for Diagnostic Imaging of Sensitized Tissues

R. Rudys1, 2, S. Bagdonas1, G. Kirdaite3, R. Rotomskis1, 2

1 Biophotonics group of Laser Research Center, Faculty of Physics, Vilnius University, Lithuania2 Biomedical Physics Laboratory, Institute of Oncology, Vilnius University, Lithuania

3 State Research Institute Centre for Innovative Medicine, Vilnius University, LithuaniaE-mail: [email protected]

Optical imaging using an intrinsic fluorescence contrast of tissues has made significant inroads to clinical applications in recent decades. Fluorescence imaging strategies have often been developed for microscopy applications and then translated to preclinical optical imaging techniques. In general, fluorescence can be characterized by the quantum yield of the fluorophores, their excitation and emission spectra, the polarization state of the emission and the fluorescence lifetime [1]. The principal endogenous tissue fluorophores include collagen and elastin crosslinks, NADH, oxidized flavins (FAD), lipofuscin, keratin and porphyrins, however, their fluorescence spectra are broad and overlapping. Fluorescence lifetime imaging (FLIM) technique relies on the fluorescence lifetime of a fluorophore, which changes in response to physiochemical effects such as local polarity, pH, temperature and protein binding and photophysical effects such as FRET and quenching, but is generally immune to imaging artifacts due to changes in concentration or instrument effects [2]. FLIM allows distinguishing different fluorophores or their states even with overlapping fluorescence spectra. Medical applications inspire an increasing interest in exploiting FLIM of tissue autofluorescence and sensitized fluorescence for clinical diagnosis of biological pathologies. The inflamed synovium in the case of rheumatoid arthritis (RA), a chronic inflammatory disease of the joints, exhibits many features typical for neoplastic tissue, inciting numerous attempts to employ endogenous porphyrins, induced by 5-aminolevulinic acid, for diagnostic and therapeutical purposes in rheumatology [3].This study presents preliminary investigations on FLIM aimed to distinguish healthy, inflamed and sensitized tissues with a focus on fluorescence of endogenous porphyrins in synovium and cartilage tissues of rabbit rheumatoid arthritis model. To measure the lifetimes a pulsed diode laser (20 MHz, 405 nm) (PDL 800-B, PicoQuant GmbH) was coupled to a laser scanning microscope Nikon “Eclipse TE2000”. FLIM was performed using a single-channel time correlated single photon counting (TCSPC) module PicoHarp 300 and a single channel SPAD detection unit set at 650±75 nm spectral range.The lifetime data analysis allowed us to characterize the sensitized rabbit knee synovium and cartilage tissues based on the different accumulation of several endogenous porphyrins with different fluorescence lifetimes. The obtained FLIM images have been compared with corresponding morphological data.

References

[1] J. R. Lakowicz, Principles of Fluorescence Spectroscopy, 2nd ed. (Springer, 1999).[2] W. J. Akers et al., Biological application of fluorescence lifetime imaging beyond microscopy, Proc.

of SPIE Vol. 7576, 757612 (2010).[3] R. Rudys et al., Spectroscopic assessment of endogenous porphyrins in a rheumatoid arthritis

rabbit model after the application of ALA and ALA-Me, Journal of Photochemistry and Photobiology B: Biology, 119:15–21 (2013).


Near Real Time, Accurate, and Sensitive Microbiological Safety Monitoring Using an All-Fibre Spectroscopic Fluorescence System

F. Vanholsbeeck1, S. Swift2, E. Bogomolny1

1 Department of Physics, The University of Auckland, New Zealand 2 School of medical sciences, The University of Auckland, New Zealand

Email: [email protected]

Enumeration of microorganisms is an essential microbiological task for many research fields. Various tests for detection and counting of microorganisms are used today such as a standard plate count with or without membrane filtration, Adenosine Triphosphate (ATP) testing, polymerase chain reaction (PCR), flow cytometry detection and others1–3. However, most of the current methods to enumerate bacteria require either long incubation time for limited accuracy, or use complicated protocols along with bulky equipment. We developed an accurate, portable, optical system, called the optrode, for near real time detection of bacteria in water. The concept is based on a well-known phenomenon that the fluorescence quantum yields of some nucleic acid stains significantly increase upon binding with nucleic acids of microorganisms. The fluorescence signal increase can be correlated to the amount of nucleic acid present in the sample. As all microorganisms contain nucleic acids, this sensor can be used for all microbial species. While the development of optical methods for the detection of microorganisms is not new, none have met industrial and/or research needs for sensitivity, specificity and accuracy.4

Our system is able to detect a wide range of bacteria concentrations without dilution or filtration (102–108 CFU/ml). This high sensitivity is due to efficient light delivery with an appropriate collection volume and in situ fluorescence detection as well as the use of sensitive CCD spectrometer. By monitoring the laser power, we account for laser fluctuations while measuring the fluorescence signal. Also a synchronized laser shutter allows us to achieve a high SNR with minimal integration time, thereby reducing the photobleaching effect. Computerized data processing and multivariate analysis further decrease the fluorescence measurement variance. The results have shown that bacteria count from different water origins using our optical setup along with multivariate analysis presents a higher accuracy and a shorter detection time compared to standard methods. For example, in a case where the fluorescence signal is calibrated to the water batch regression line the relative standard deviation of the optical system enumeration varies between 21–36%, while the heterotropic plate count counterpart is 41–59%. The data are acquired in near real time using our portable device. In contrast, plate counting requires days.In summary, our optrode offers a robust method for bacterial detection and enumeration in water. The major advantages of the optrode are sensitivity, near real time measurements and the ability to detect a high dynamic range of bacteria concentrations between 102–108 CFU/ml. Recent improvement of the fibre probe allows a sensitivity of 1 CFU/ml.

References

[1] J. T. Keer et al. “Molecular methods for the assessment of bacteria viability” J. of Microbiol. Meth. 53(2), 175 (2003).

[2] I. O. McHugh et al. “Flow Cytometry for the Rapid Detection of Bacteria in Cell Culture Production Medium” J. of the Int. Soc. for Anal. Cytol. 71(12), 1019 (2007).

[3] D. E. Turner et al. “Efficacy and Limitations of an ATP-Based Monitoring System”. J Am. Assoc. Lab. Anim. Sci. 49(2), 190 (2010)

[4] S. Cabredo et al. “Bacteria spectra obtained by laser induced fluorescence” J. of Fluoresc. 17(2), 171 (2007).


Express Control of Plants General State by Using the New Generation of the Instrumental Tools

K. E. Shavanova, M. V. Taran, O. A. Marchenko, N. F. StarodubNational University of Life and Environmental Sciences of Ukraine, Kyiv, Ukraine


The main fields of the fluorescence method application for registration are in the estimation and prediction of the influence on several factors on the vital functions of the chlorophyll synthesizing organisms: 1) climatic conditions; 2) fertilizers; 3) substances that contaminate the environment; 4) viral infections; 5) means of chemical plant protection and 6) water regimes. Moreover, there is a possibility to select optimal processing methods for the crop plants commercial cultivation, to provide monitoring and productive plants control in real-time regime and to perform monitoring of the environment in certain regions [1].The intensity of chlorophyll fluorescence depends on photosynthetic activity. After the leaf irradiation the intensity of chlorophyll fluorescent signal is increasing at first and then it reduces slowly. This effect is named as Kautsky effect or effect of induction of chlorophyll fluorescent (IChF). The form of this curve is rather sensitive to changes in the photosynthetic apparatus of plants during adaptation to different environmental conditions. The advantages of this method are the following: high self-descriptiveness, expressiveness, non-invasiveness and high sensibility. It gave a possibility developing the portable device “Floratest”, which lets to estimate in several seconds the plant state without plant damage in the Institute of Cybernetics of NAS of Ukraine [2, 3].The patterns of IChF parameters were studied during 2010–2013 years. It has been made an estimation of the chlorophyll complex functional condition of the horse chestnut leafs photosynthetic apparatus in the street plantings of Kiev. It was revealed, that the coefficient of plateau Kpl on the Kautsky curve can be used as the test index for an early selection of horse chestnut forms which are resistant to the influence of a complex of environmental factors. The value of Kpl ≥ 0,4–0,5 testifies about a susceptibility to a damage horse chestnut genotypes by the chestnut moth and especially on street plantings near highways. Thus, the used express-method can essentially accelerate process of selection of plants, resistant to the various environmental factors, including different pests, in comparison with the visual diagnostics. The results indicated that the fluorescent indices are also sensitive to the effects of such stressors as acidification, salinity, dehydration. The overall level of fluorescence of chlorophyll in the leaves of beans that grew under the above-mentioned conditions was 960, 864 and 928 relative units, respectively. While in the control experiments this value was reached the level of 1024 and above. Thus, based on obtained results we conclude that above listed stressful conditions cause substantial disruption of the photosynthetic apparatus in plants as well as result in corresponding decreasing the intensity of the chlorophyll fluorescence and indices of adaptation to stress. This set of indicators should serve as a signal for the urgent adoption of appropriate decisions in farming to prevent further loss of yield.

References

[1] K. Rohàček, Chlorophyll fluorescence parameters; the definitions, photosynthetic meaning and mutual relationship, Photosynthetica, V. 40, № 1, P. 13–29 (2002).

[2] V. Romanov et al., Portable device ‘Floratest’ as tool for estimating of megalopolis ecology state, Intelligent Engineering: International book series ‘Information Science and Computing’, V. 11, P. 9–15 (2009).

[3] I. D. Voytovych, Intelligent sensors, Kyiv, 514 p. (2007).


Structured Nano-Porous Silicon as Novel Transducer at Control of Mycotoxins in Environmental Objects

N. F. Slyshyk, N. F. StarodubNational University of Life and Environmental Sciences, Kyiv, Ukraine


The presence of mycotoxins in agricultural products necessitates large scale testing of a wide range of sample material to ensure the safety of food and feed. Mycotoxins produced by special strains of fungi’s are as very serious risk factors for health of human and animals [1]. Today’s practical requirements for methods of food control has increased sharp.It is needed for the solving problems of the express control of T2 mycotoxin and patulin for the development of the effective protective measures to avoid non-desirable effects of the intoxications [2].To meet all the requirements of practice in respect of high sensitivity of analysis as well as simplicity, cheapness and rapidity of its fulfillment we propose to use of structured nano-porous silicon (sNPS) as transducers for the immune biosensors with the registration of the specific signal on the basis of changes of chemiluminescence (ChL) or photocurrent of this structure.At the beginning of the measurement the specific Ab in the volume of 1µl was placed on the photoresistor surface between the contacts. Then this solution was evaporated at the room temperature or at the air stream. The direct voltage (5 V) from the stabilized power supply was applied to the ohmic contacts and the current was measured by the digital voltmeter of B7-35 type at the absence of lighting (dark regime) as well as the photocurrent (the difference between the light and dark currents) was registered at the lightening of the sensitive surface by the white spectrum light (source A, illumination of 7000 lux). At the drawing of Ag layer on the sensitive plate and after its drying the measurements of the dark and light current were repeated. These measurements were made after the immune complex formation (interaction of Ag with specific Ab in the serum blood) too. The control of the reaching of the sensor initial state was done according to the reduction of the dark current value after washing of the sensitive surface by the buffer solution. The time of the single analysis was 5–10 min only. It was shown that the sensitivity of such biosensors allows determining T-2 mycotoxin and patulin at the concentration of 10 ng/ml during several minutes. The total duration of the fulfilment of all processes including Ab immobilization and steps of measurements was about 40 min. The obtained calibration curves with the model solution of T-2 mycotoxin and patulin open perspective for the practical application of the proposed immune biosensor in case of the determination of others mycotoxins.

References

[1] V. V. Smirnov, et al. Mycotoxins: fundamental and applied aspects. Modern problems of toxicology, 2000, N1, 5–12.

[2] N. F. Starodub, et al. Biosensors for the Determination of Mycoyoxins: development, efficiency at the analysis of model samples and in case of the practical applications. In book: “Lecture Notes of the ICB”, 86, 81–101 (2010).


Effect of Solutions of Ferum and Zinc Nano-particles on the Plant Photosynthetic Activity

R. Sonko, K. Lopatko, N. StarodubNational University of Life and Environmental Sciences, Kyiv, Ukraine


Nano-technologies foresee the widely use of the preparations of the latest generation of the engineering achievements in agriculture for fertilizing and protection of plants. Today, the nanoparticle powders and colloidal solutions of biogenic metals find often wide application for increasing productivity and resistance of plants to abiotic and biotic environmental factors. Microelements in plants are also involved in redox processes, catalysis and synthesis on the atomic-molecular level. Sometimes, just content million particles per cent of metal ions is enough for normal functioning of plants and a small excess from it can cause toxic poisoning. The mechanisms of the activation and protection of nano-materials may be different in each case and they require special consideration.We have studied the effect of colloidal solutions of nano-particles of zinc and iron on the photosynthetic apparatus of plants. Nano-dimensioned samples of the metals were obtained by spark processing their grain. The state of the photosynthetic apparatus of plants was determined by the measurement of the induction of chlorophyll fluorescence using a portable fluorometer “Floratest” developed in the V.M. Glushkov Institute of Cybernetics of National Academy of Sciences of Ukraine.Effects of nano-colloidal solutions appear most active during the early stages after treatment. It should be noted that the nano-particles of zinc and iron separate used cause an increasing intensity of the photosynthetic activity (PhSA) and the level of maximum fluorescence of plants. The combination of the nano-particles of both metals in one experiment stipulated an increase of the PhSA intensity whereas the maximum level of fluorescence remained on the control level. Further action of the above mentioned colloidal solutions manifested in reducing PhSA intensity of plants and then returned to the level of the performance control. It was found that nano-colloidal solutions of iron are most active while combining them with solutions of zinc causes a prolonged effect on the performance of the PhSA of plants.Determination of the vegetative masses of plants showed that after their treatment by the colloidal solutions of metals the level of this parameter was increased. The weight of the aboveground parts of plants treated with the combined colloidal solutions of Fe and Zn was increased on 6.3% and 7.1%. At the processing plants with a mixture of colloidal solutions of Fe and Zn this parameter was increased on 32% in the comparison with the control level. At the sometime in the experimental variants it was strong developed powerful root. The largest mass of roots was obtained in the case of application of Fe nano-particles (68%), slightly less – a mixture of colloidal solutions of two metals Fe and Zn (60%). Weight of roots in the variant where plants were treated by the Zn colloidal solution was increased on 25% only.Thus, the treatment of plants by the colloidal solutions of both metals (iron and zinc) showed a positive effect on plants and increased their vegetative mass. Simultaneously, immediately after treatment it was observed changes of chlorophyll fluorescence induction caused by the solutions of the above mentioned metals and after some time tis parameter returned to normal level.

55POSTER PRESENTATIONS

POSTER PRESENTATIONS

Signal Analysis of Multi-spectral Photoplethysmograph Biosensor

L. AsareInstitute of Atomic Physics and Spectroscopy, University of Latvia, Riga, Latvia


Photoplethysmography (PPG) is a simple and low-cost optical technique that can be used to detect blood volume changes in the micro vascular bed of the tissue. It is often used for non-invasive measurements at skin surface [1]. Reflection photoplethysmography detects the tissue back-scattered radiation with time resolution [2]. The PPG signal consists of AC and DC components. The AC component reflects the vascular pulsations, and the DC component represents the light scattered from relatively steady blood volume and tissue layers, which are the components without a pulsatile signal [3].Multi-spectral photoplethysmograph (MS-PPG) biosensor intended for analysis of peripheral blood volume pulsations at different vascular depths has been experimentally tested. Light emitting diodes with four different wavelengths were used as the light emitters. A single photodiode with multi-channel signal output processing was used as the light detector.The experimental data were analyzed with data analysis and graphing software Origin 8.0. Fig. 1 show the systole rising time difference between wavelengths. It show that systole rising time is smaller at 519 nm and 632 nm wavelength where dominate hemoglobin absorption over oxyhemoglobin absorption and bigger at 454 nm where oxyhemoglobin absorption dominate.

Fig. 1. The systole rising time difference between wavelengths in graph.

This study analyzed rising time difference between wavelengths at systole maximum, wavelengths relations between systole and diastole peak difference. The proposed methodology is discussed.

References

[1] Allen, J. “Photoplethysmography and its application in clinical physiological measurement”, Physiol. Meas. Vol. 28, R1–R39 (2007).

[2] Ugnell, H., Öberg, P. Ǻ., “Time variable photoplethysmographic signal: its dependence on light wavelength and sample volume,” Proc. SPIE 2331, 89–97 (1995).

[3] Asada, H. H., et al., “Mobile monitoring with wearable photoplethysmographic biosensors,” IEEE Eng. Med. Biol. Mag. 22, 28–40 (2003).

56 POSTER PRESENTATIONS

Multimodal Device for Assessment of Skin Malformations

A. Bekina1, V. Garancis2, U. Rubins1, E. Zaharans1, J. Zaharans1, L. Elste1, J. Spigulis1

1 Institute of Atomic Physics and Spectroscopy, University of Latvia, Riga, Latvia2 Telemedica SIA, Riga, LatviaE-mail: [email protected]

Many spectral imaging devices are commercially available and used to detect certain skin pathology; however an alternative cost-efficient device can provide an advanced spectral analisys of skin. Multimodal device for diagnosis of pigmented skin lesions was developed and tested. A polarized LED light source illuminates the skin surface at four different wavelengths – blue (450 nm), green (540 nm), red (660 nm) and infrared (940 nm). Spectra of reflected light from the 25 mm wide skin spot is imaged by a CMOS sensor [1]. Four spectral images are obtained for mapping of the main skin chromophores. The specific chromophore distribution differences between different skin malformations were analised and information of subcutaneous structures was consecutively extracted. The chromophore concentration was expressed by from the natural logarithm of relation between two intensities of monochrome light illuminations [2]:

(1)

where C – respectively hemoglobin, bilirubin, melanin or erythema index map, A0 – first calibration constant, A1 – second calibration constant, d – thickness of the measured tissue, I1 and I2 – intensities of diffuse reflected light from the skin related for particular chromophore. The distribution of hemoglobin is more pronounced in hemangiomas and angiomas, bilirubin map shows mostly bruises, melanin appears in both malignant and benign skin lesions like melanomas and birthmarks, however erythema index map corresponds to blood perfusion [3]. The software algorithm allows to overlay original image and a map for better monitoring of the skin malformation’s areas with more pronounced chromophore concentration. Multimodal device as well as chromophore mapping has been successfully tested in the clinic. Computerized image processing allows to observe more detailed structure of skin malformations to avoid the subjectivity of human skin assessment with the naked eye.

References

[1] J. Spigulis, et al. A device for multimodal imaging of skin. Proc. SPIE 8574, Multimodal Biomedical Imaging VIII, 85740J (March 13, 2013); doi:10.1117/12.2003510

[2] Non-invasive device and method for measuring bilirubin levels. Patent «0023742 A1» US (2013).[3] A. Bekina, et al. Multispectral assessment of skin malformations by modified video-microscope.

Latv. J. Phys. Techn. Sci., v. 49, No. 5, pp. 4–8 (2012)


Ellipsoidal Reflectors in Biomedical Diagnostic

М. А. Bezuglyi, N. V. BezuglayaKyiv Polytechnic Institute (Ukrainian National Technical University), Kiev, Ukraine


From the optical point of view of most biological tissues (BT) are optically turbid mediums, which are inherent significant scattering and selective absorption. For describing the optical properties of these mediums we are using the following characteristics: thickness d, refractive index n, absorption coefficient μa, scattering coefficient μs and the scattering anisotropy factor g. For determine this parameters usually using lenses, fiber or mirrors optics or integrating shears. This work describe a features of using the ellipsoidal reflectors for determine the optical properties of biological tissue in vitro and in vivo conditions. The schemes [1] have been implemented for research in vitro as the experimental setup, and for in vivo studies – in the form layout based on stereoscopic microscope. The principle of measurement is as follows: monochromatic radiation from a laser is directed into the cavity through an ellipsoidal mirror transmitting of optical system, located at the entrance of the reflector. Reflection from a plane mirror, the light is directed to the object under study. Due to the interaction of laser radiation with BT, which is located in the focal plane of the ellipsoidal reflector, we can observe characteristic spot of scattering, which image is projected in the second focal plane of the ellipsoid, which focuses on certain zoom microscopes. The optical system of the microscope and mounted adapter on the microscope conveys not stereoscopic image (like in Fig. 1 of etalon simpls) on the camera, which is connected to a computer that uses specialized software.

а) b) Fig. 1. Images and graphics of spatial distribution of brightness in the focal plane of the ellipsoid of

rotation for etalons: steel (a) and duralumin (b) bars

The results of simulation of walk of inverse Monte Carlo method [1] is the absorption coefficient μa and scattering μs, and also the scattering anisotropy factor g. Thus, using the results of experimental studies with the using photometric systems with ellipsoidal reflectors and inverse MC we can get optical parameters BT.

References

[1] M. A. Bezuglyi, А. V. Yarych, D. V. Botvinovskii, On the possibility of applying a mirror ellipsoid of revolution to determining optical properties of biological tissues // Optics and Spectroscopy, 2012, Vol. 113, No. 1, pp. 101–107. Pleiades Publishing, Ltd., 2012.

[2] Безуглий М. О., Ботвиновський Д. В., Зубарєв В. В., Коцур Я. О., Метод фотометричного дзеркального еліпсоїда обертання для дослідження шорсткості поверхні // Методи та прилади контролю якості, Ів.-Франк., 2011, вип. № 27, с. 77–83.


Spatial Photometry of Scattered Radiation by Biological Objects

N. V. Bezuglaya, М. А. BezuglyiKyiv Polytechnic Institute (Ukrainian National Technical University), Kiev, Ukraine


Notion of the character of light scattering by biological objects (BO) allows defining clinically important indexes associated with a change of their optical properties. Indicatrix of single-act scattering, modeled in numerical experiment by the phase function (mainly Henyey-Greenstein), can be obtained by approximation of the indicatrix of the multi-act scattering in the framework of a real experiment. That can significantly reduce the error in the determination of the optical parameters of the different BO. The analysis of the existing gonio- and goniospectro- photometric systems not revealed implemented the mechanism of simultaneous spatial registration scattered BO of the light streams in a wide solid angle.Therefore was suggested the system [1] for parallel spatial photometry of scattered radiation by biological objects (Fig. 1). The principle of its functioning is the following. Collimated beam of the optical radiation falls on BO and scattered in different directions, gets on the n number of sensors placed at equal distances. Equality distances provide a means of placing of the photoreception devices on two hemispherical surfaces. Radius hemispheres depend on a pre-defined photometric distance for particular biological structure.To determine the optimal distance of photometry (radius hemispheres) was created optoelectronic system goniometric type, which allows registering simultaneously reflected and transmitted radiation through biological object. The system consists of two receivers, which are located on the limbs of a goniometer in direction of transmitted and reflected light. Receivers are able to move along the limbs, determining the most appropriate signal/noise ratio in specific areas for particular biological environment. The signal is processed by exclusive software «IMSOB» [2].The most rational way for designated authors of the study during a multi-element photometry is creation measuring system on the basis of photodiodes, the signal from which is controlled by the microcontroller. To solve programming the micro controller is the author has carried out electronic simulation of a multi-element photometric system in the environment of PROTEUS (Labcenter Electronics). Based on the results of the simulation be the model design of the measuring system (Fig 1.) using photodiodes 4 (BPW21R), ampli-fiers 5 (LM358), multiplexor 6 (MPC508), microcontroller 7 (АTmega8535) and photometric sphere with 32 mm radius.

References

[1] N. V. Bezugla, U. V. Chmyr, O. V. Kuzmenko and M. O. Bezuglyi, Ua Patent No. 75382.[2] O. V. Kuzmenko, N. V. Bezugla and M. O. Bezuglyi, Ua Patent No. 44754.

Fig. 1. System for parallel spatial photometry of scattered radiation by biological objects


Elastic Light Single-Scattering Spectroscopy for Detection of Dysplastic Tissues

M. Canpolat, T. Denkceken, A. Akman, E. Alpsoy, R. Tuncer, M. Akyuz, M. Baykara, S. Yucel, I. Bassorgun, M. A. Ciftcioglu, G. A. Gokhan,

E. Inanc Gurer, E. Pestereli, S. KaraveliAkdeniz University, Turkey


Elastic light single-scattering spectroscopy (ELSSS) system has been developed and tested in diagnosis of cancerous tissues of different organs. ELSSS system consists of a miniature visible light spectrometer, a single fiber optical probe, a halogen tungsten light source and a laptop. Measurements were performed on excised brain, skin cervix and prostate tumor specimens and surrounding normal tissues. Single fiber optical probe with a core diameter of 100 µm was used to deliver white light to and from tissue. Single optical fiber probe mostly detects singly scattered light from tissue rather than diffused light. Therefore, measured spectra are sensitive to size of scatters in tissue such as cells, nuclei, mitochondria and other organelles of cells. Usually, nuclei of tumor cells are larger than nuclei of normal cells. Therefore, spectrum of singly scattered light of normal tissue is different than tumor tissue. The spectral slopes were shown to be positive for normal brain, skin and prostate tissues and negative for the tumors of the same tissues. Sign of the spectral slopes was used as a discrimination parameter to differentiate tumor from normal tissues for the three organ tissues. Sensitivity and specificity of the system in differentiation between tumors from normal tissues were 93% and %100 for brain, 87% and 85% for skin, 93.7% and 46.1% for cervix and 97% and 87% for prostate.


A Program to Assist in Recognition of Emotional States

B. ChoinskiPolitechnical University of Gdańsk, Gdańsk, Poland


The paper introduces the interaction between an application and a device monitoring eye movements in real time. The purpose of this article is an attempt to describe the observed links between arousal, anxiety, stress and a complex logical task. Authors would like to present the current state of knowledge regarding the biological mechanisms of emotion elicitation and the mechanisms underlying motivation. The program, which was created for the purpose of the experiment, is to assist in determining the state of arousal and the increase/decrease of the arousal, while measuring the effectiveness of the logical tasks. As a result of arousal or lack of it some people can react inappropriately to the stimulation, which can reduce the quality of mental life of the individual. Researchers want to start experiments which may help to define the optimal level of arousal for people performing tasks associated with visual processing and requiring abstract thinking (colors, figures, emotions shown in facial images) in order to solve a test properly and to achieve the best possible result. The authors also intend to connect the application to other devices that can determine current arousal or its changes and to use the application for relaxation techniques.

References

[1] Górski J. et al., Fizjologiczne podstawy wysiłku fizycznego (2002).[2] Strelau J. et al., Psychologia. Podręcznik akademicki (2004).[3] Traczyk W. Z., Fizjologia człowieka w zarysie (2002).


Optical Properties of ZnO Nanorods Grown by Chemical Bath Deposition

M. O. Eriksson1, Z. N. Urgessa2, J. R. Botha2, K. F. Karlsson1, P. Bergman1, P. O. Holtz1

1 Department of Physics, Chemistry, and Biology, Linkoping University, Linkoping, Sweden2 Department of Physics, Nelson Mandela Metropolitan University, Port Elizabeth, South Africa


Modifying the diameter and post growth annealing of ZnO nanorods grown by chemical bath deposition enables control of optical properties such as photoluminescence (PL) intensity and exciton lifetimes. The optical properties of the nanorods have been studied by micro-PL spectroscopy. The ZnO nanorods are grown by immersing a ZnO seed coated Si substrate in a mixture of hexamine and Zn(NO3)26H2O in deionized water while heating the reactants in a water bath. Nanorods with diameters from 30 nm to 150 nm have been synthesized, and post growth annealing at various temperatures has been performed. [1] The PL spectra are dominated by near band edge (NBE) emission in the ultraviolet spectral range at low temperature. As the temperature of the ZnO nanorods is increased, free exciton emission appears and defect related emission [2–4] becomes more pronounced. The defect related emission intensity can be increased in relation to the NBE emission by annealing. Smaller nanorod diameters result in a higher concentration of defect states with respect to the volume of the nanorods, and a reduction of the PL intensity (see Fig. 1). Carrier lifetimes in the range of less than five picoseconds to several hundred picoseconds have been observed. The lifetime of the D0X state increases for annealed nanorods, because of a reduction of certain defect states. Reducing the rod diameter results in an NBE emission with a more clear biexponential decay. Varying the diameter of the ZnO nanorods and annealing them are methods for tuning their optical properties.

2 2.5 3 3.5 4

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nts/

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x500

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Fig. 1. µPL spectra of ZnO nanorods with average diameters of 120 nm and 30 nm, obtained at (a) room temperature, and (b) at 5 K.

References

[1] Z. N. Urgessa et al., Growth and Characterization of ZnO Nanorods Using Chemical Bath Deposition, PhD Thesis, Nelson Mandela Metropolitan University, (2012).

[2] K. Vanheusden et al., Mechanisms behind green photoluminescence in ZnO phosphor powders, Journal of Applied Physics, vol. 79, p. 7983–7990 (1996).

[3] M. Liu et al., Point defects and luminescence centres in zinc oxide and zinc oxide doped with manganese, Journal of Luminescence, vol. 54, p. 35–42 (1992).

[4] S. A. Studenikin et al., Fabrication of green and orange photoluminescent, undoped ZnO films using spray pyrolysis, Journal of Applied Physics, vol. 84, p. 2287–2294 (1998).


Identification of Deposits on Contactlens Surface

S. Fomins1, I. Zakutajeva2, M. Ozolinsh1, 2 1 Institute of Solid State Physics, Riga, Latvia

2 Optometry and Vision Science Dept. University of Latvia, Riga, LatviaE-mail: [email protected]

Modern soft contact lens surface is irrigated by tear fluid while placed on the eye cornea. Most used hydrogel and siliconehydrogel contact lenses absorb proteins and lipids. Depending on the surface physical and chemical properties protein deposits should be potentially different from lipid deposits (jelly bumps, mucin balls), which are observable with biomicroscope in clinical practice. Deposits formed structures are microscopic and don`t produce any noticeable optical behaviour in transmitting light. To observe lipids and proteins contact lens with its basis was placed on the transparent circular disk (Fig. 1). Four white LEDs were used as a light source set up from the four sides in 45 degree angle to the plane. Transparent disk allowed light to pass only through the circular basis of the contact lens, leaving the central part clear and dark for observation. Light entering the basis of the lens filled the inner part of it with light. Most of the contact lens surface appeared dark (transparent) and only in places of differing diffraction bright spots were observed. CCD camera was used capture the images of light scattered by structures on the surface of contact lenses. Due to saturation at the disk only central part around 10 mm in diameter become available for the analysis. Microscopic structures produced a cloud like films on the contact lens surface, while bigger parts appear as more bright singular entities. Results of the proposed analysis are comparable to the sessile drop technique detected surface wetting angle results. Technique has a potential for further microscopic and spectroscopic development.

Fig. 1. Surface of the SiH contact lens.

Acknowledgement

The research is supported by the ERAF project No 2010/0259/2DP/2.1.1.1.0/10/APIA/VIAA/137.

Reference

Lorentz et al., Lipid deposition on hydrogel contact lenses: how history can help us today, Optom Vis Sci. 84(4), 286-295 (2007).


Bi-Spectral Palm Image Acquisition for Person Recognition

R. Fuksis, M. Pudzs, R. Ruskuls, T. Eglitis, D. Barkans, M. GreitansInstitute of Electronics and Computer Science, Riga, Latvia


Increased identity fraud in last years stimulates a new biometric system development. To obtain higher precision and also higher security against biometric parameter falsification, developers more often use more than one biometric parameter, therefore building multimodal biometric systems. However by increasing the amount of biometric data to be processed, the complexity of the data processing and the cost of the hardware also increase. Authors propose the bi-spectral palm biometric system that is implemented in FPGA based hardware for real time image processing. System consists of an image acquisition module that is being operated in visible and near-infrared light spectrum for palm print and palm vein image acquisition. If bi-spectral method is used, the falsification of biometric parameters, by showing the photo of a palm to the system, is significantly reduced. Because only real palm will provide unique parameters both in visible and infrared spectrum while a photograph of a palm shown to the system will provide the same information in both spectral images. Authors also use previously developed image processing method that provides a fast and unique information extraction from captured images. This method is called Non-Halo Complex Matched Filter (NH-CMF) [1]. Also the amount of data after the filtering is significantly reduced to reduce complexity of post-filtering computations. To provide secure and fast comparison of the biometric data a biometric encryption method called BioHash [2] is also implemented in order to secure the sensitive biometric information. Finally obtained biocode is compared on the smart card for additional safety. A complete multi-modal biometric system that employs a match-on-card concept with a real-time image processing is shown in Fig. 1.

Fig. 1. Multi-modal biometric system.

References

[1] M. Pudzs, et al. Complex 2D matched filtering without Halo artifacts. In Systems, Signals and Image Processing (IWSSIP), 2011 18th International Conference on, 1–4, 2011.

[2] R. Belguechi, et al. Biohashing for Securing Minutiae Template. In Pattern Recognition (ICPR), 2010 20th International Conference on, 1168–1171, 2010.


Correlation Mapping Method of OCT for Visualization Blood Vessels in Brain

O. A. Izotova, A. L. Kalyanov, V. V. Lychagov Saratov State University, Saratov, RussiaE-mail: [email protected]

The brain is the center of the nervous system of almost all living organisms. It serves the essential functions – centralized control over the other organs of the body, the behavior of the organism and all its activity. The diseases of brain are life-threatening and may cause to death. One of such diseases is intracranial hemorrhage (ICH). It is a major problem especially among newborn babies [1]. Intracranial hemorrhage usually hasn’t got obvious symptoms, and because of that can’t be determined with the help of standard methods [2]. So, in order to understand the nature of the disease, the microcirculation of blood is analyzed. The microcirculation serves key functions within the body including regulation of blood pressure, body temperature, blood flow within tissues and delivery of nutrients and removal of metabolic waste products. So, structural changes of it can lead to the various diseases. On this basis a series of experiments was done. These experiments, in which laboratory rats were exposed to stress and injections of adrenaline, showed, that latent stage of ICH is characterized by decrease of venous blood outflow and the loss of sensitivity of sagittal vein to vasoconstrictor effect of adrenaline. So, stress-related changes of the cerebral venous blood flow (CVBF) can be the source of this disease.In this paper registration CVBF was made with the help of commercially available Thorlabs Swept Source OCT System, using the correlation mapping method [3, 4]. In this method values of correlation coefficient of several images are analyzed. It values are on the range of 0 ± 1. If in the region are big structural changes, it takes the value 0. If the regions are static, correlation coefficient is 1. In the result of the algorithm the correlation map was obtained. By the resulting map the diameter and volume of vessels were calculated, which is necessary for examination of effects of adrenalin to the vessels and identification symptoms of ICH.

References

[1] Gaupta S. N. et al., Intracranial hemorrhage in term newborns: management and outcomes, Pediatr. Neurol. No. 40, P. 1–12 (2009).

[2] Osborn D. A. et al., Hemodynamic and antecedent risk factors of early and late periventricular/intraventricular hemorrhage in premature infants, Pediatrics. No.112, P. 33–39 (2003).

[3] Enfield J. et al., In vivo imaging of the microcirculation of the volar forearm using correlation mapping optical coherence tomography (cmOCT) ,Biomedical Optics Express. Vol. 2, No. 5. P. 1184–1193 (2011).

[4] Enfield J. et al., Correlation mapping method for generating microcirculation morphology from optical coherence tomography (OCT) intensity images, J. Biophotonics Vol. 4, No. 9, P. 583–587 (2011).


Assessment of Efficiencies of Electroporation and Sonoporation Methods by Fluorescence RGB Imaging Method

D. Jakovels1, A. Lihachev1, J. Spigulis1, S. Satkauskas2, M. Tamosiunas2, C. W. Lo3, W. S. Chen3

1 Biophotonics Laboratory, Institute of Atomic Physics and Spectroscopy, University of Latvia, Riga, Latvia2 Vytautas Magnus University, Kaunas, Lithuania

3 Department of Physical Medicine & Rehabilitation, National Taiwan University, Taipei, TaiwanE-mail: [email protected]

Local electroporation (EP) and sonoporation (SP) can be used for targeted delivery of drugs and genes. The efficiency of the therapy usually is evaluated by fluorescence microscopy, flow cytometry. Fluorescence spectrometry has been reported as the non-invasive, low cost and sensitive method for the determination of drug uptake. Green fluorescence protein (GFP) can be used as a marker indicating efficiency of the procedure. Fluorescence intensity of GFP can be attributed to delivered concentration of drugs or genes.The aim of this study was to build simple RGB device for fluorescence in vivo imaging that could be used for efficiency assessment of EP and SP methods by measuring distribution and accumulation of GFP concentration. Device for fluorescence in vivo imaging is based on the color RGB camera and 473 nm cw laser. It was proposed that qualitative and quantitative evaluation of GFP presence in the skin can be expressed as ratio of intensities at green (G) and red (R) channels:

cGFP = I(G)/I(R).

20 laboratory in vivo measurements on mice were performed to test the method. Examples of color images of fluorescence overlapped with parameter cGFP maps are shown in Fig. 1.

Fig. 1. Color images of fluorescence overlapped with parameter cGFP maps.

References

[1] S. Satkauskas, et al. “Towards the mechanisms for efficient gene transfer into cells and tissues by means of cell electroporation.” Expert Opin Biol Ther 12, 275–86 (2012).

[2] K. C. Tsai, et al. “Differences in gene expression between sonoporation in tumor and in muscle.” J Gene Med 11, 933–940 (2009).


Low-coherent Measurement Method of Human Blood Hematocrit

M. Jedrzejewska-SzczerskaGdansk University of Technology, Department of Metrology and Optoelectronics, Gdańsk, Poland


Measurement of blood parameters is important since it provides information on the total ability of patient. One of the important analytes is the blood hematocrit (HCT), defined as the ratio of packed red blood cells volume to whole blood volume. During the last thirty years low-coherence measurement methods have gained popularity because of their unique advantages. They enable measurements of the absolute value of the optical path differences, which is still an unsolved problem in high-coherent interferometry. Furthermore, the use of the spectral signal processing makes this method immune for any change of the optical system transmission. The developed low-coherent fiber-optic set-up for hematocrit measurement has been made from: an optical processor (Optical Spectrum Analyzer Ando AQ6319 with wavelength resolution of 1 nm, wavelength accuracy of ±50 pm and close-in dynamic range of 60 dB). As a low-coherence source the superluminescent diode with Gaussian spectral intensity distribution (Superlum Broadlighter S1300-G-I-20) with following optical parameters: l0 = 1290 nm, Dλ = 50 nm has been used. As a sensing interferometer a low-finness fiber-optic Fabry-Perot interferometer has been implemented. With the use of elaborated low-coherent system with Fabry-Perot interferometer, the hematocrit value of numerous blood sample has been measured. Experimental investigation has given a series of recorded spectra. In fig. 1a the measured signals of the blood sample with HCT = 35.2% is shown. Mathematical processing of the measured signals provided information about measurand from the spectrum of signal is shown in Fig. 1b.

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a) b)Fig. 1. a) Measured signal of the blood sample with HCT = 35.2%; b) Experimental results of the change of number of signal spectra fringes vs. hematocrit value: dots – measured value, dash line – regression

line. (R2 – determination coefficient of statistical model of HCT vs. number of fringes relationship)

The results of experimental works showed that implemented experimental set-up provided good quality of the measured optical signals by offering great value of visibility of the measured signal, exhibits immunity for changes of the optical signal polarization and got simple configuration. The investigation of this method confirms its ability for the hematocrit control with appropriate measurement accuracy.


Reliability and Validity of Optoelectronic Method for Biophotonical Measurements

K. Karpienko, M. S. WrobelGdansk University of Technology, Department of Metrology and Optoelectronics, Gdańsk, Poland


Reliability and validity of measurements is of utmost importance when assessing measuring capability of instruments developed for research. In order to perform an experiment which is legitimate, used instruments must be both reliable and valid. Reliability estimates the degree of precision of measurement, the extent to which a measurement is internally consistent. Validity is the usefulness of an instrument to perform accurate measurements of quantities it was designed to measure. Statistical analysis for reliability and validity control of low-coherence interferometry method for refractive index measurements of biological fluids. The low-coherence interferometer is sensitive to optical path difference between interfering beams. This difference depends on the refractive index of measured material. To assess the validity and reliability of proposed method for blood measurements, the statistical analysis of the method was performed on several substances with known refractive indices. Analysis of low-coherence interferograms considered two approaches: counting the number of interference fringes and the mean distances between them. Performed statistical analysis for validity and reliability consisted of Grubb’s test for outliers, Shapiro-Wilk test for normal distribution, T-statistic and Levene’s test. Overall the tests proved high statistical significance of measurement method with p-value < 0.001 of measurement method.

References

[1] Jędrzejewska-Szczerska M. et al., Low-Coherence Fibre-Optic Interferometric Sensors, Acta Physica Polonica, 4, 624–646 (2011).

[2] Kimberlin C. L. et al., Validity and reliability of measurement instruments used in research, American Journal of Health-System Pharmacy, 65(23), 2276–2284 (2008).


Blue Autofluorescence of Biological Fluids and Carbon Nanodots and Its Eventual Use in Clinical Praxis

A. Kuznetsov1, A. Frorip1, M. Ots-Rosenberg2, A. Sunter2 1 AS Ldiamon, Tartu, Estonia

2 Tartu University, Tartu, EstoniaE-mail: [email protected]

Non-protein blue fluorescence (λemmax = 410 – 430 nm) of biological fluids (BFBF) (serum, urine, hemodialysate) is not identified yet. BFBF has similarity with BF of carbon nanodots (CND) aqueous solutions. The aim of this presentation is twofold: 1) to scrutinize the optical properties of BFBF and BFCND and 2) to find the correlations between BFBF and clinically acknowledged characteristics of chronic kidney disease patients (CKD Pt) such as C-reactive protein, creatinine, urea etc. Results. Thorough experimental study conducted on BFBF and sugar derived CND revealed that up to eight optical parameters coincide or correlate strongly: main excitation/emission maxima; excitation/emission spectra; spectral shift of emission bands to the long wave length region by decrease of excitation energy Eexc (“red shift”); change of emission bands width; asymmetry parameters of emission bands; fluorescence intensity dependence on pH; “hidden” structure in the absorption spectra around 320 nm; specific intensity increase at 385 nm after reaction with aluminium salts. Linear correlation (R2 ~ 0.7) between the intensity of BFBF in hemodialysates of CKD Pts and CRP concentration in serum has been found. The same holds for creatinine and urea in HD.

Normalised blue �uorescence

y = 0.0031x + 0.1592R2 = 0.6807

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 20 40 60 80 100 120 140 160 180CRP, mg/L

Inte

nsit

y, a

.u.

Conclusion

We presume that BFBF and BF of carbohydrates derived carbon nanodots have a common origin. Two phenomena can be investigated from the single physical position what helps to identify BFBF and use it for clinical monitoring.


Fluorescence Lifetime Spectroscopy: Potential for In-vivo Estimation of Skin Fluorophores

Changes after Low Power Laser Treatment

A. Lihachev, I. Ferulova, J. SpigulisInstitute of Atomic Physics and Spectroscopy, University of Latvia, Riga, Latvia


Fluorescence lifetime detection system (Fig. 1.) has been used for detection of in-vivo skin autofluorescence lifetimes [1]. The aim of this study is estimation of quantitative changes of skin endogenous fluorophores changes after low power cw laser provocation. Autofluorescence lifetimes of in-vivo normal skin were consequentially registered at 405 nm, 470 nm and 510 nm picosecond laser excitation. The skin autofluorescence lifetimes were registered before and after cw laser provocation via y-shape optical fibre. Skin optical provocations were performed during 1 min by several visible low power cw lasers with power density up to 20 mW/cm2 [2, 3].

PC and SPC-150

Photon counting detector PMC-100-4

Pico-second laser

shape optical �ber

Sample

e.g. skin

Fig. 1. Picosecond fluorescence lifetime setup for detection of skin autofluorescence lifetimes.

References

[1] T. Vo-Dinh, Biomedical Photonics Handbook, Tuan Vo-Dinh, ed. (SPIE PRESS, WA USA, 2003). [2] A. Lihachev et al., Low power cw-laser signatures on human skin, Quant. Electron., v. 40, No. 12,

1077–1080, (2010).[3] I. Ferulova et al., Influence of low power CW laser irradiation on skin hemoglobin changes, Proc.

SPIE 8427, 84273I (2012).


Fluorescence Spectroscopy for Estimation of Anticancer Drug Sonodestruction in Cell Culture

A. Lihachev1, M. Tamosiunas2, S. Satkauskas2, J. Spigulis1 1 Institute of Atomic Physics and Spectroscopy, University of Latvia, Riga, Latvia

2 Biology Department, Vytautas Magnus University, Kaunas, LithuaniaE-mail: [email protected]

Anticancer drug and gene delivery in to the cell can be achieved by local delivery of high intensity ultrasound. This drug delivery process is called by sonoporation [1]. It is believed that and sonoporation induce transient pores in the plasma membrane allowing non-permeate molecules to get access into the cells. This technique has gained widespread application in biotechnology and medicine [2]. However, the impact of ultrasound on pharmacological and optical properties of targeted drug is not completely understood as well as destruction of drug molecules under high intensity ultrasound. In this paper we studied the impact of high intensity ultrasound on drug fluorescence and pharmacological properties by means of fluorescence spectroscopy [3]. Fluorescence decay of anticancer drug (bleomycin) during applied high intensity ultrasound in shown in Fig. 1.

0 1 2 3 4 50.2

0.4

0.6

0.8

1.0

Nor

mal

ized

�uo

resc

ence

(r.u

.)

Time, min

357 nm

Fig. 1. Bleomycin fluorescence decay kinetic during applied high intensity ultrasound. Bleomycin fluorescence was excited by 270 nm UV-LED. Kinetic was obtained at a wavelength of 357 nm,

applied ultrasound pressure 500 kPa.

References

[1] S. Satkauskas et al., Towards the mechanisms for efficient gene transfer into cells and tissues by means of cell electroporation, Expert Opin Biol Ther, vol. 12, pp. 75–86, 2012.

[2] K. Ferrara et al., Ultrasound microbubble contrast agents: fundamentals and application to gene and drug delivery, Annu Rev Biomed Eng., vol 9, pp. 415–447, 2007.

[3] J. Lesins et al., Fluorescence\ spectroscopy for the detection of cell electroporation efficiency, Kaunas University of Technology, ISSN 2029-33870, pp. 246–249, 2011.


Development of Multispectral Imaging Method for Skin Pathology Diagnostics

I. Lihacova1, A. Derjabo2, A. Bekina1, J. Zaharans1, J. Spigulis1

1 Biophotonics Laboratory, Institute of Atomic Physics and Spectroscopy, University of Latvia, Riga, Latvia 2 Latvian Oncology Centre, Riga, Latvia


A multispectral imaging method was developed using multispectral imaging camera Nuance EX. Spectra from skin and skin pathologies- nevus, basal cell carcinoma and melanoma- was acquired in range from 450 to 950 nm with step 10 nm. The spectral curve differences of different pathologies were analysed and specific melanoma parameter was developed. The greatest spectral differences between melanomas and other skin pathologies were observed at three wavelengths – 540 nm, 650 nm and 950 nm. From the literature, it is known that 540 nm corresponds to the maximum absorption of the blood haemoglobin [1], at 650 nm melanin absorption is more pronounced [1, 2], and at 950 nm dermal melanin can be seen [3]. Melanoma diagnostic parameter was expressed by the following formula:

, (1)

where OD540, OD650 and OD950 are the optical densities at 540 nm, 650 nm and 950 nm.Melanoma diagnostic parameter has been successfully used in the clinic. Overall, 17 histologically confirmed melanomas and 65 nevi identified by dermatologists were investigated in this study [4]. Sensitivity of the approach was 94% and specificity was 89%.The image processing technique was improved and adapted for modified Dino-Lite video microscope [5]. A simplified form of Eq. (1) was used:

, (2)

where I545, I660 and I940 represents the intensities of the skin-reflected light from 545 nm, 660 nm and 940 nm light- emitting diode (LED) light source. LEDs’ wavelengths were chosen close to wavelengths from Eq. (1). For the further method’s development the reference method, for instance confocal microscopy, would be required.

References

[1] S. Prahl: Tabulated molar extinction coefficient for hemoglobin in water. [http://omlc.ogi.edu/spectra/hemoglobin/summary.html]

[2] T. Sarna et al.: The physical properties of melanin. [http://omlc.ogi.edu/spectra/melanin/eumelanin.html]

[3] R. Anderson et al., “The optics of human skin,“ J Invest Derm, 77(1):13–19 (1981).[4] I. Diebele et al., “Clinical evaluation of melanomas and common nevi by spectral imaging,” Biomed

Opt Express, 3(3): 467–472 (2012).[5] A. Bekina et al., “Multispectral assessment of skin malformations by modified video- microscope,”

Latvian Journal of Physics and Technical Sciences, 5(49), 4–8 (2012).


Methodology for Assessment of Low Level Laser Therapy (LLLT) Irradiation Parameters in Muscle Inflammation Treatment

M. Mantineo1, 2, A. M. Morgado1, 2, J. P. Pinheiro3

1 IBILI – Institute for Biomedical Research on Light and Image, Faculty of Medicine, University of Coimbra, Portugal

2 Instrumentation Center, Department of Physics, University of Coimbra, Portugal3 Faculty of Medicine, University of Coimbra, Portugal


Several studies in human and animal models show the clinical effectiveness of low level laser therapy (LLLT) in reducing some types of pain, treating inflammation and wound healing [1–5]. However, more scientific evidence is required to prove the effectiveness of LLLT since many aspects of the cellular and molecular mechanisms triggered by irradiation of injured tissue with laser remain unknown. We evaluate the effect of different LLLT parameters (wavelength, dose, power and type of illumination: pulsed or continuous) in the treatment of inflammation induced in the gastrocnemius muscle of Wistar rats, through the quantification of four representative cytokines (TNF-α, IL-1β, IL-2 and IL-6) [6–8] and histological analysis of muscle tissue. Here, we present a new methodology concerning animal’s treatment with laser dose evaluation for continuous illumination.During the development of our work, we found that following the three Rs principle (Reduction, Replacement and Refinement) [9] was of key importance, since it enabled us to minimize the quantity of animals used for the experiments while preserving statistical relevance. Moreover, following the ARRIVE guides [10] to perform a detailed work including all the necessary sections was equally important.

References

[1] J. D. Carroll. “Photomedicine and LLLT literature watch” Photomed. Laser Surg., vol. 27, no. 5, p. 829, Oct. 2009.

[2] V. Campana, et al. “He-Ne laser on microcrystalline arthropathies” J. Clin. Laser Med. Surg. 21, 99–103. 2003.

[3] F. Aimbire, et al. “Effect of LLLT Ga-Al-As (685 nm) on LPS-induced inflammation of the airway and lung in the rat” Lasers Med. Sci. 20, 11–20. 2005.

[4] V. Campana, et al. “The relative effects of He-Ne laser and meloxicam on experimentally induced inflammation” Laser Therapy 11, 36–41. 1999.

[5] R. Martin. “Laser-accelarated inflammation/pain reduction and healing” Pratical Pain Management 3, 20–25. 2003.

[6] A. M. B. Bilate, “Inflamação, citocinas, proteínas de fase aguda e implicações terapêuticas,” Temas de Reumatologia Clínica 8, 47–51. 2011.

[7] J. L. Gallin, “Inflammation,” in Fundamental Immunology, W. E. Paul, ed., Raven Press, pp. 721–733. 1989.[8] D. K. Male, et al., Advanced Immunology, J.B. Lippincoll Company, Gower Medical Publishing. 1991.[9] Russell, R. Burch. “The principles of humane experimental technique”. Publisher, Methuen, 1959.[10] C. Kilkenny, et al. “Improving Bioscience Research Reporting: The ARRIVE Guidelines for Reporting

Animal Research”. PLoS Biology. Volume 8. June 2010.


Applicability of Diffusion Approximation in Analysis of Diffuse Reflectance Spectra

from Healthy Human Skin

P. Naglic1, L. Vidovic2, M. Milanic2, L. L. Randeberg3, B. Majaron2

1 Faculty of Mathematics and Physics, University of Ljubljana, Slovenia 2 Jožef Stefan Institute, Ljubljana, Slovenia

3 Norwegian University of Science and Technology, Trondheim, NorwayE-mail: [email protected]

Measurement of diffuse reflectance spectra (DRS) is a popular experimental approach to non-invasive determination of tissue optical properties, as well as objective monitoring of various tissue malformations. In skin, e.g., DRS depend and can in principle be used to quantitatively assess various lesion specifics such as concentrations of epidermal melanin and dermal blood, oxygen saturation level, epidermal and dermal thickness, etc. Propagation of light in strongly scattering media, which is governed by Boltzmann transport equation, is often treated in so-called diffusion approximation (DA). The major advantage of such an approach is that it offers enclosed analytical solutions for tissues with layered structure, which includes human skin. Despite the fact that DA solutions are known to be inaccurate near strongly absorbing structures and tissue boundaries [1, 2], the practicality of this approach makes it quite popular, especially when it comes to solving the inverse problem of extracting some of the above mentioned tissue properties from DRS.In our study, we analyse the discrepancies between DRS spectra obtained using the DA solutions for three-layer skin models and more accurate predictions from Monte Carlo (MC) modelling for the same skin structure and chromophore content. In contrast with earlier similar reports, we perform a quantitative analysis of the artefacts which result from the above discrepancies when extracting the parameters of skin structure and composition by fitting the DA solutions to the MC spectra. Tentative conclusions from such analysis will be tested also on measurements of seasonal changes of DRS in human volunteers.

References

[1] T. Spott and L. O. Svaasand, Appl. Opt., vol. 39, 6453–6465 (2000)[2] L. L. Randeberg et al., “Performance of diffusion theory vs. Monte Carlo methods”, Proc. SPIE,

vol. 5862, 58620O (2005).


Water Detection in Skin by Dual-Band Photodiodes

I. Saknite, E. Kviesis, J. SpigulisBiophotonics Laboratory, Institute of Atomic Physics and Spectroscopy, University of Latvia, Riga, Latvia


The concept of non-invasive skin assessment has an important role in every-day work for medical doctors. Simple spectral imaging systems have been used for analysis of chromophore (bilirubin, haemoglobin) mapping in bruises, birthmarks and other skin lesions by differences in diffuse reflectance images at different wavelengths in the visible range. Water in this sense can also be regarded as a chromophore as its absorption spectrum has significant differences in visible and near-infrared spectral range, and its concentration distribution in skin could be interesting when non-invasively looking at different skin lesions and in determination of skin moisture level [1]. In this study, a dual-band photodiode (Thorlabs) was used as a detector together with illumination of three different LEDs of wavelengths 1400 nm, 1200 nm, and 980 nm. Fig. 1. shows the spectral sensitivity of the dual-band photodiode, spectra of illumination LEDs, as well as the theoretical water absorption spectrum [2].With the new experimental setup, images of skin areas of a different moisture level were acquired for mapping of water. Results show that this method is very promising in an accurate determination of moisture level in skin.

Fig. 1. Spectral sensitivity of the photodiode, spectra of illumination LEDs, and relative absorption spectrum of water.

References

[1] I. Saknite, et al., Determination of chromophore distribution in skin by spectral imaging, Proceedings of SPIE, vol. 8474, 84740K (2012).

[2] Web page http://omlc.ogi.edu/spectra/


Muscle Tissue Saturation in Humans Studied with Two Non-invasive Optical Techniques: a Comparative Study

A. Shaharin1, E. K. Svanberg2, 3, I. Ellerstrom3, A. A. Subash1, D. Khoptyar1, S. Andersson-Engels1, J. Akeson3

1 Department of Physics, Lund University, Lund, Sweden, 2 Department of Anaesthesiology and Intensive Care Medicine, Lund University,

3 Skane University, Hospital, Malmö, SwedenE-mail: [email protected]

The motivation of this work is to perform a comparative study between the two noninvasive optical techniques for measuring Muscle tissue saturation (StO2), the first one is Photon Time-of-flight spectrometer (PTOFS) developed in the Group of Biophotonics, Lund University, and the other is a Continuous Wave Near Infrared Spectroscopy system (INVOS 5100C Regional Saturation Monitor; Somanetics Corporation, Troy, MI, USA). Analytically, StO2 is defined by ratio between the amount of oxygenated hemoglobin by total amount of hemoglobin. Thus,

Tissue Saturation,

INVOS 5100C measures light attenuation in tissue using two wavelengths to evaluate the concentration of de-oxygenated and oxygenated haemoglobin. The attenuation of injected photons in the tissue of interest is affected by both absorption and scattering by tissue chromophores and the spectroscopic system of INVOS 5100C is unable to separate this two effects. However PTOFS enables the determination of the optical properties i.e. scattering and absorption separately and thus gives more accurate result.

Fig. 1. Mean values (Standard Deviation in gray) of muscle tissue oxygenation (StO2) obtained by CW-NIRS(INVOS 5100C) and PTOFS measurements in 17 adult volunteers subjected to four

physiological events (I-IV). PTOFS 30 mm and PTOFS 40 mm indicate values obtained at 30 and 40 mm distance, respectively, between the source and the detectors.

To perform the study a campaign was arranged after the approval of the Regional Human Ethics Committee at Lund University, Sweden. And a written informed permission was obtained from the 21 (17 were taken for comparison) healthy adult volunteer participants (8 women and 13 men). The participant’s right arm was extended with the palm facing upwards and the PTOFS sensor along with two INVOS sensors were attached to it. A blood pressure cuff was attached to the upper side of the arm to observe provocations such as immediate venous and arterial occlusion or progressive venous through arterial occlusion. The oxygen saturation values obtained from CW-NIRS was in the range from 70–80%. However, from PTOFS it was in the range of 55–60%, which is much more realistic according to the normal physiology of muscle tissue.


Biophotonic Sensor of Small Changes in the NaCl Concentration in Aqueous Solution

L. Surazynski1, Sz. Buda2, M. Jedrzejewska-Szczerska1 1 Department of Metrology and Optoelectronics, Gdansk University of Technology, Gdansk

2 Faculty of Chemistry, Jagiellonian University, KrakowE-mail: [email protected]

Gathering information of a wide range of parameters is crucial in many fields. Networks of optical sensors are widely used in medicine, structural health monitoring and telemedicine. Optical sensors have gained popularity in those areas because of their unique advantages: relatively simple configuration, high resolution, low thermal inertia and potentially low cost. Furthermore, they have small size and weight. Being made from dielectric materials, they are immune to electromagnetic radiation.Method for detection of small changes in the NaCl concentration in aqueous solution is described. It is based on the use of optoelectronic sensors with detection layer (Fig. 1a). Such layer has been designed and elaborated. It can be noted from Fig. 1b. that detection layer confirmed its ability for making NaCl concentration changes measurement with appropriate parameters. Presented preliminary results can be the basis for building NaCl concentration sensor ready for practical applications.

a) b)

Fig. 1. a) sensor set-up; b) optical intensity vs. wavelength for different concentration of NaCl in aqueous solution: 1 – 0,1%; 2 – 0,2%; 3 – 0,5%; 4 – 1,0%.

Acknowledgment

This study was partially supported by the Foundation for Polish Science under the grant no. 173/UD/SKILLS/2012 as well as DS Programs of the Faculty of Electronics, Telecommunications and Informatics, Gdańsk University of Technology.

References

[1] F. Baldini, Analytical and Bioanalytical Chemistry, 393, 1089 (2009)


Biocidal Effects of Silver and Zink Oxide Nanoparticles on the Bioluminescent Bacteria

M. V. Taran1, N. F. Starodub1, A. M. Katsev2, M. Guidotti3, V. D. Khranovskyy4, A. A. Babanin3, M. D. Melnychuk1

1 National University of Life and Environmental Sciences of Ukraine, Kyiv, Ukraine2 Crimean State Medical University, Simferopol, Ukraine

3 CNR-Institute of Molecular Sciences and Technology, Milano, Italy4 Linkoping University, Linkoping, Sweden


Nanotechnology is a relatively young area of science which is rapidly entering into our lives and very quickly developing. At the same time, the nanoparticles themselves are not something entirely new and can be obtained from the milling of materials or in the course of chemical reactions (Ju.A. Krutjakov, 2008). At present the industrial production of a variety of nanoparticles of hundreds of thousands of tons. The most “popular” are nanoparticles of carbon (nanotubes, fullerenes, graphene), silica, gold, silver, cupper, zinc oxide and titanium dioxide. In the nano state many substances acquire new properties and are biologically very active (I. Lopes, 2012).Data from various studies on the impact of nanoparticles on organisms rather contradictory, but forget about the seriousness of this problem is not necessary. Need to continue the investigations of the effects of nanoparticles on living organisms and to devise methods for their detection in the environment. In this regard the development of nano sciences and nanotechnology creates an additional anthropogenic factor which requires a detailed study. Research in this area has led to the emergence of nanotoxicology – the special section of toxicology which has task to assess the impact of nanoparticles on living organisms and the environment (C.S. Yah, 2012).It was investigated the effect of nano-particles of silver and zinc oxide in the combination with alginate on the bioluminescent bacteria of Photobacterium leiognathi Sh1. It was stated that silver nano-particles in the comparison with that from zinc oxide have a more high toxic effect on the bioluminescent bacteria. The nano-particles and their ions have the same effect but it was absent in case of their combination with alginate. The effective inhibiting concentration for silver nanoparticles was about 0,3–0,4 µg/ml and it was higher up to two times for such structures of zinc oxide. The absence of sodium chloride in the medium to be analyzed prevents the formation of colloidal particles of large size and effective inhibition concentrations of metal derivatives were declined. It was concluded that the biocidal action of metal nano-structures, in particular, NBS can be linked with the formation of metal (silver) ions when dissolved and due to the damaging effect of the nanoparticles themselves to the membrane of the bacterial cell and, as a result of it, increase their sensitivity to copper ions.

References

[1] Krutjakov Ju. A. et al., Synthesis and abilities of silver nano-particles: achievements and perspectives, Russian Chem. Rev., 77, P. 242–269 (2008).

[2] Lopes I. et al., Toxicity and genotoxicity of organic and inorganic nanoparticles to the bacteria Vibrio fischeri and Salmonella typhimurium, Ecotoxicol., 21, P. 637–648 (2012).

[3] Yah C. S. et al., Nanoparticles toxicity and their routes of exposures. Pak. J. Pharm Sci., 25, P. 477–491 (2012).


Micron Scale Dispersion Mapping for Tissue Recognition in Optical Coherence Tomography

N. Lippok1, 2, S. Murdoch1, F. Vanholsbeeck1

1 Department of Physics, The University of Auckland, New Zealand 2 Auckland Bioengineering Institute, The University of Auckland, New Zealand


Optical coherence tomography (OCT) is a non-invasive imaging technique based on low coherence interferometry that provides high resolution 3D images of small samples with a depth range of a few mm in turbid media1. Typically the depth resolution is inversely proportional to the light source bandwidth and can be as good as 1 µm in recent experiments. OCT has adapted methods that offer tissue differentiation and functional information such as elastography2 and speckle contrast3. Material differentiation can also be obtained by using the electric susceptibility of a medium. For example, absorption has been used to differentiate lipid from water4 and polarization sensitive OCT uses the tissue birefringence, i.e. the angular dependence of the refractive index, as a contrast agent5. Chromatic dispersion, i.e. the frequency dependence of the refractive index, is seen as detrimental in OCT as dispersion imbalance between the two arms of the interferometer degrades the resolution of the OCT setup. We have been working on different techniques, both hardware and software, to compensate for dispersion imbalance and to restore the system resolution to the theoretical prediction6,7. In some cases, the numerical techniques present the advantage of being able to measure the sample dispersion. Recently we have been working on using chromatic dispersion for material differentiation. Using a tri-band swept source configuration, we can identify water and lipid at a sample thickness of 40μm and 90μm, respectively. Our preliminary results reveal exciting prospects for medium identification or differentiation at a resolution suitable for OCT. This is possible even without dispersion calculation, by only evaluating the sign and magnitude of the walk-off. The successful encoding of lipid on such scales could have profound consequences for clinical applications and may aid the detection of lipid filled plaques in coronary arteries prior to rupture.

References

[1] D. Huang et al. “Optical coherence tomography,” Science 254, 1178 (1991).[2] J. Schmitt, “OCT elastography: imaging microscopic deformation and strain of tissue,” Opt. Express

3, 199 (1998).[3] T. R. Hillman et al. “Correlation of static speckle with sample properties in optical coherence

tomography,” Opt. Lett. 31, 190 (2006).[4] J. M. Schmitt et al. “Differential absorption imaging with optical coherence tomography,” J. Opt.

Soc. Am. A 15, 2288 (1998).[5] M. R. Hee et al. “Polarization-sensitive low-coherence reflectometer for birefringence

characterization and ranging” J. Opt. Soc. Am. B 9, 903 (1992).[6] N. Lippok et al. “Dispersion compensation in Fourier domain optical coherence tomography using

the fractional Fourier transform,” Opt. Express 20, 23398 (2012).[7] N. Lippok et al. “Single-shot speckle reduction and dispersion compensation in optical coherence

tomography by compounding fractional Fourier domains” accepted in Optics Letters.


A Development of Multispectral Approach to Evaluate the Cardiometabolic Risk Related to Alterations

in Body Composition

K. Volceka1, L. Ozolina-Moll1, E. Svampe1, J. Zaharans2, E. Zaharans2, Z. Marcinkevics1

1 Faculty of Biology, Department of Human and Animal Physiology, University of Latvia, Riga, Latvia2 Institute of Atomic Physics and Spectroscopy, University of Latvia, Riga, Latvia


With the increasing percentage of the populace becoming overweight, even obese, it has become increasingly important for early diagnosis of diseases associated with excess weight and obesity. Obesity is an important risk factor for many diseases that reduce life expectancy such as type 2 diabetes, cardiovascular diseases (CVD), metabolic syndrome and certain types of cancers. Nowadays there are no standardized criterions which allow early detection of diseases related to obesity, in addition, to differentiate metabolic bening and maling obesity. There is significant difference in body fat localisation. Scientific evidences reveal several physiological and genetic differences between intraabdominal visceral fat and peripheral subcutaneous fat. Such differences are also reflected in their contrasting roles in the pathogenesis of obesity-related cardiometabolic problems. Determination of thickness of different fat storages (visceral and subcutaneous), in addition to anthropometrical parameters and ultrasound measurements of intima-media thickness (IMT) in common carotid artery could become a progressive and precise CVD risk markers.Although there are a number of techniques for body composition (in particular, body adipose tissue) assessment in clinics and in field-survey, but the methods are primarily aimed to determine the absolute values of the parameters, be it total body fat percentage, adipose tissue volume or thickness of adipose tissue. An easily definable parameter that would relate to ultrasonographically determined IMT, which is closely related to adiposity, is needed.Therefore, an optic prototype for risk evaluation is proposed. The operating principles of the device are based on the light-tissue interaction and in the principle that the penetration depth increases with greater source-detector (SD) distance. The different kinds of human tissue, such as adipose tissue, skeletal muscle and skin, have different light interaction properties at different wavelengths.The probe of the prototype contains three light sources of multiple wavelengths situated at different distances (SD1, SD2, and SD3) from a photodetector. For the data analysis using the single wavelength method the ratios between these intensities is calculated in order to find an index. The high resolution B-Mode ultrasound imaging has been selected as a referent method for the subcutaneous adipose tissue thickness measurement in young healthy female students, as well as for measurement of IMT and visceral fat indices. The acquired optical data was complexly compared to ultrasonographically obtained data.


Novel Combined Fluorescence/Reflectance Spectroscopy System for Guiding Brain Tumor Resections – Hardware Considerations

Z. Xie, H. Xie, M. Mousavi, M. Brydegaard, J. Axelsson, S. Andersson-EngelsLund University Medical Laser Centre, Lund, Sweden


Glioblastoma multiforme (GBM) has long been known as the most common and aggressive form of brain malignancy. The morphological similarities of the malignant and surrounding tissue cause difficulties to distinct the tumors during surgery. In order to achieve better results in resecting malignant brain tumours, improved methods for precise tumor resection have long been investigated. High-resolution intraoperative ultrasound, image guided frameless stereotaxy, intraoperative CT or MRI imaging methods, and fluorescence microscopy are all adapted for the localization and identification of tumour tissue. Unfortunately none of these supplementary methods seem to provide sufficiently accurate information to solve all challenges for accurate surgical guidance. In order to assistant the resection during neurosurgery of malignant lesion in real time, an optical fiber based system is developed in this project. The idea in this project is to distinguish the tissue types by combining information from tissue auto-fluorescence, fluorescence from the contrast agent ALA-induced PpIX, as well as diffuse reflected light. Malignant glioma cells will take up ALA as a consequence of a damaged blood-brain-barrier in tumour tissue, and be converted it into strongly fluorescent protoporphyrin IX (PpIX). The PpIX concentration in the tumor can reach 50 times the concentration in the surrounding brain. With 405 nm excitation light, the PpIX would fluorescence intensively around 635nm. In order to build a compact system insensitive to ambient light, a multi-LED source including 5 LEDs (365 nm, 405 nm, 530 nm, 640 nm and white light) is employed. All LEDs are square-wave modulated at a high frequency. This allows lock-in detection to suppress any influence of 50 Hz ambient room light. The 5 LEDs are coupled to individual optical fibers. The distal ends of the fibers are surrounding a central detection fiber in an optical probe. The detection fiber guides the light back to a compact detection unit. This is constructed for directing light of different wavelengths to independent light detectors (1 Photodiode for 405 nm channels, and 4 Avalanche Photodiodes (APDs) for the other wavelength bands (510 nm, 530 nm, 640 nm, 660 nm). After efficient amplification electronics, the signals are directed to a data acquisition board (NI-DAQ card) for data acquisition and further signal processing. In the signal processing, the influence of noise is first reduced by signal filtering, and the signals are then multiplied by a calibration factor to provide a true signal level. The calibration considers optical losses in the signal path as well as detector efficiency. The internal gain in the APDs varies with the temperature. Therefore the temperatures of the APDs are measured and the correction factor is a function of temperature. The average signal strengths of each channel for certain time period are calculated. The different signals are now available for further signal processing and analysis.The system is tested in several laboratory experiments with liquid phantom, it is proved to have stable performance and high sensitivity to low PpIX concentration under strong ambient light sources. The next step is to test the system in clinics on superficial skin cancer at Skåne University Hospital in Lund and later in Glioblastoma surgeries an Linköping University Hospital. Analysis of the ability to distinguish different tissue types will be conducted utilizing multivariate calibration techniques, and such studies are planned.


Excitation-Emission Matrices Measurements of Human Cutaneous Lesions –

Tool for Fluorescence Origins Evaluation

A. Zhelyazkova1, E. Borisova1, L. Angelova1, E. Pavlova2, M. Keremedchiev2

1 Institute of Electronics, Bulgarian Academy of Sciences, Sofia, Bulgaria2 University hospital “Queen Jiovanna-ISUL”, Sofia, Bulgaria


Autofluorescence has been proven to be a very sensitive and accurate method for detection of early changes in many cancer types. This method has the potential to provide real-time diagnosis of malignant and premalignant skin tissue. However, skin is a very complex multilayered and inhomogeneous organ with spatially varying optical properties that complicate the analysis of the fluorescence spectra. Nevertheless of the difficulties related to detection and analysis of cutaneous lesions fluorescent data, this technique is one of the most prominent and widely applied in laboratorial and pre-clinical investigations for early skin neoplasia diagnosis.Many researchers proposed investigations using different excitation wavelengths and tried to determined whether the intensity of the fluorescence emission alone or in combination with spectral shape changes for a given excitation lambda, could be used to distinguish normal skin from neoplasia.We used spectrofluorimeter FluoroLog 3 (HORIBA Jobin Yvon, France) with additional fiber – optic module – F-3000, allows to measure the fluorescent properties of samples which can not be put in a standard cuvette, such as tissue samples.Ex vivo point-by-point measurements were taken from the excised tumour lesions and outwards from surrounding skin. Autofluorescence using different excitation wavelengths for differentiation of tummor and healthy tissue is detected, forming excitation – emission matrix of data. For the experiments we used freshly excised basal cell carcinoma (BCC) tumors and benign nevi material. Excitation applied is in 280–440 nm region. Fluorescence emission were measured between 300 nm and 800 nm.Our autofluorescence spectra recorded ex vivo are from endogenous fluorophores existing in the tissue. We do not expect to have signals from co-enzymes such as NADH, NADPH, FAD and flavins, due to their fast degradation in excised tissues. We measure fluorescence signals mainly from structural compounds in the skin and its lesions. Fluorescence spectrum in the range 320–370 nm excitation at UV range of the spectrum 250–290 nm is dominated by aromatic amino acids tyrosine, phenylalanine and tryptophan, structural proteins such as collagen (excitation maximum around 320–350 nm and emission maximum around 400–440 nm) and elastin (excitation maximum around 290–325 nm and emission around 340 and 400 nm), their cross-links, as well as keratin are observed in the EEM data received. The decrease in the fluorescence intensity of the malignant tissues is due to cancer induced destruction of collagen and elastin cross-links surrounding the tumor cells. Specific changes, related to tumour stage and type are evaluated and discussed in our report.

Acknowledgements

This work is supported by the National Science Fund of Bulgarian Ministry of Education, Youth and Science under grant № DMU-03-46/2011 “Development and introduction of optical biopsy system for early diagnostic of malignant tumors”.


Multimodal Imaging: Combined DUV, SHG and TPEF Microscopy

V. Zubkovs1, 2, F. Jamme2, S. Kascakova3, 4, F. Chiappini3, 4, F. Le Naour3, 4, M. Réfrégiers2

1 University of Latvia Institute of Chemical Physics, Riga, Latvia2 Synchrotron SOLEIL, beamline DISCO, Gif sur Yvette, France

3 University Paris-Sud, Institut Andre Lwoff, Villejuif, France4 INSERM U785, Villejuif, France


This study shows the advantages of combining nonlinear microscopies: Second Harmonic Generation (SHG), Two Photon Excitation Fluorescence (TPEF) and Synchrotron Deep Ultraviolet light (DUV) microscopy for research on pathological samples. The mentioned methods were used to analyse the two worldwide most common non-alcoholic fatty liver disorders: simple steatosis and non-alcoholic steatohepatitis (NASH) as well as collagen fibres organization in rat tail tendon. The experiments were performed at the synchrotron SOLEIL facility at bioimaging beamline DISCO.SHG is a coherent nonlinear phenomenon which has found many applications in microscopy of biological issues. For example: cartelization of renal fibrosis in kidney [1], imaging of starch grains [2], presentation of brain micro tubular network [3], scoring of liver fibrotic stages [4], etc. The method is highly selective for several compounds: collagen, amylopectin, myosin, and tubulin.Contrary to SHG, TPEF is an incoherent process. TPEF can be recorded simultaneously, but separately from SHG, providing information about endogenous compound composition. Due to deep penetration of near infrared light, a two photon microscopy has an advantage over conventional methods. DUV bright field microscopy is a high resolution technique. It is an excellent tool for non-destructive analysis of many intrinsic autofluorescent compounds in a specimen (tryptophan, tyrosine, elastin, collagen, lipopigments, etc. [5, 6]). In this study DUV microscopy was used for visualization of tryptophan and tyrosine distribution, as well as for collagen and elastin imaging in liver and rat tendon. Combination of SHG and DUV microscopies allowed characterising globular and fibrilar collagen types in liver pathological sections.

References

[1] Strupler, M., et al., Second harmonic microscopy to quantify renal interstitial fibrosis and arterial remodeling, Journal of Biomedical Optics, 13 (2008).

[2] Mazumder, N., et al., Stokes vector based polarization resolved second harmonic microscopy of starch granules, Biomedical Optics Express, 4, pp. 538–547 (2013).

[3] Kwan, A. C., et al., Optical visualization of Alzheimer’s pathology via multiphoton-excited intrinsic fluorescence and second harmonic generation, Optics Express, 17, pp. 3679–3689 (2009).

[4] Guilbert, T., et al., A robust collagen scoring method for human liver fibrosis by second harmonic microscopy, Optics Express, 18, pp. 25794–25807 (2010).

[5] Jamme, F., et al., Deep UV autofluorescence microscopy for cell biology and tissue histology, Biology of the cell, pp. 1–12, (2013).

[6] Wagnieres, G. A., et al., Invited Review ln Vivo Fluorescence Spectroscopy and Imaging for Oncological Applications, Photochemistry and Photobiology, 68, pp. 603–632 (1998).

Documents

PROGRAMME ABSTRACTS - LU · FP7-REGPOT-CT-2011-285912 Conference organizers Scientific Committee Prof. Janis Spigulis, Latvia – Chair Dr. Janis Alnis, Latvia Dr. Aigars Ekers, Latvia