Biomedical Imaging and Sensing
Andrei Zvyagin
Centre for Biophotonics and Laser SciencePhysics, School of Physical SciencesBiomedical Engineering, School of Information Technology and Electrical Engineering
The University of Queensland
Projects
Coherence-domain imaging techniques, as applied to cells and live biological tissueFull-field Fourier domain optical coherence
tomography (3F-OCT)Synthetic-aperture confocal microscopy
Dialysis-assisted fibre optic spectroscopy for drug sensing in situ
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Full-field Fourier domain OCT
Digitalsensor
Obj
ect
Sweptsource
C
Fourierlens
f f
Coupler
•3D-data cube is acquired•Contains comprehensive information on the sample 3D structure and
its optical scatter•Signal-to-noise ratio is optimized•Suitable for ophthalmology applications in vivo•Relies on rapid broadly-tuneable laser swept-source
Dialysis-assisted fibre optic spectroscopy
Fluorophores
Tissue constituents
Illumination To spectrum analyzer
Setup for measuring fluorophore concentration in tissue using DAFOS. Inset, DAFOS sampling head. Illumination light guided through a fibre F, is emerging from the dialysis membrane DM, tip.
Illumination fibre
Microdialysis membrane
Tissue
Collection fibre
Needleibre
F
DM
•Small molecules, e.g. drugs, enter the
sampling head and detected
spectroscopically•Compared with traditional microdialysis
tool, DAFOS is rapid•The equilibrium between the solute and
intercellular fluid is established via
diffusion, DAFOS is potentially sensitive
and reliable• The use of high-fluence UV radiation is
now possible, as DAFOS can be light-
tight, and prevents large protein
complexes from entering the sampling
head• Enables in vivo applications of a range
of spectroscopic techniques
DAFOS
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Time response of DAFOS signal
Setup for measuring fluorophore concentration in tissue using DAFOS. Inset, DAFOS sampling head. Illumination light guided through a fibre F, is emerging from the dialysis membrane DM, tip.