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The nanoparticle-plasmon resonance
for proteomics
Bongsu, Jung
Jaehun, Seol
Final Project, ME381R
December 2 ,2004
Table of contents
• Proteomics
• Motivation
• Particle surface plasmon resonance
• Fabrication method for nanostructure– Nanosphere lithography– Ultraflat nanosphere lithography
Proteomics
• Completing DNA map is not sufficient to elucidate biological function
• DNA or mRNA can’t encode the arrangement for cell signal pathway or a metabolic cascade
• Poor correlation between protein and mRNA• Post-transcriptional regulation of gene
expression problem
Motivation :Why Surface Plasmon Resonance ?(as non-labeling method)
• Current fluorescent labeling technique for proteomics is complicate and labor intensive job
• Fluorescent labeling method gives interference and photobleaching to data
• SPR is real-time, very sensitive, easy to use non-labeling technique for proteomics
Metal Nanoparticles as SensorsLocalized SPR:
• localized: Localized oscillation of an electron density wave- Probing only a very thin layer around each particle- Each particle acts as its own sensor- High field enhancements at edges- Very easy detection (UV-Vis)
Problems with localized SPR:• Size and shape have strong influence
on the resonance• Shape difficult to control above
40 nm diameter• Non-spherical particles difficult to
preserve
oEakiak
P)4
32
4)(1()2(4
)1(3
3322
Stationary depolarizationDynamic depolarization from phase difference on larger particle
Radiation damping correction
Dipole vs quadrupole resonance
J. Phys. Chem. B 2003, 107, 668-677
Dipole and quadrupole resonance is controlled by size of spheres
Dipole and quadrupole resonance is controlled by size of spheres
J. Phys. Chem. B 2003, 107, 668-677
Strong field enhancement in non-spherical shape
Journal of cluster science Vol. 10, No2. 1999, 295-317
DDA simulated electric field contours with for various shapes. (a) The innermost contour represents the grid boundaries of a 30nm sphere. The drop in intensity is from 50 to 1. (b) 2:1 spheroid has high field intensity to the high curvature periphery of the particle. The drop in intensity is from 125 to 1. (c) The truncated tetrahedron has high field intensity near the tip. The drop in intensity is from 500 to 1.
(a) (b) (c)
Huge field enhancement at tip of triangle shape when compared to spherical shape
Huge field enhancement at tip of triangle shape when compared to spherical shape
Fabrication technique : Nanosphere Lithography
•Spin-coating technique
•Slow vertical withdrawal of a substrate technique
•Tilting a substrate technique
•Horizontal movement of a substrate
Depositing method :
Fabrication technique : Nanosphere Lithography
Slow vertical withdrawal method
Appl. Phys. Lett., Vol. 77, No. 17, 23 October 2000
Fabrication technique : Nanosphere Lithography
Horizontal movement method
H, height of meniscus
R, Humidity ratio
T, temperature
C, Concentration ratio of liquid
W, Width of cuvette
Speed of horizontal movement
S, Shape of meniscus
Substrate, glass
Fabrication technique : Nanosphere Lithography
Main principles for producing monolayer
• Capillary force (Surface tension )due to meniscus formation
• Convective flow due to water evaporation
Particle convective flow
Water convective flow
Water evaporation
Surface tension
Fabrication technique : Nanosphere Lithography
Monolayer masking principle for periodic pattern of nanostructure
J. Vac. Sci. Technol. A, Vol. 13, No. 3, May/Jun 1995J. Phys. Chem. B, Vol. 103, No. 19, 1999
Frey, W., Woods, C. K., Chilkoti, A.:Adv. Mat. 12 (20), 1515 (2000)
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7
1
2
3
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1 Sphere deposition2 Metal M1 evaporation3 Sphere removal4 Metal M2 evaporation5 Low viscosity epoxy6 Mechanical support7 Dry lift-off
Fabrication technique : Ultraflat Nanosphere Lithography
Fabrication technique : Ultraflat Nanosphere Lithography
Advantages of UNSL
• Sharp corner and edges are well preserved
• Only one side is exposed to surface
• Various choices of substrate
J. Phys. Chem. B 2000, 104, 10549-10556
Conventional NSL
Conventional NSL UNSLUNSL
Adv. Mater. 2000, 12, No. 20, October 16