Biochip Array Detection based on Plasmon Resonance and Evanescent Wave Induced Scattering
Date Issued
2005
Date
2005
Author(s)
Lee, Hao-Ran
DOI
en-US
Abstract
DNA-modified metallic nanoparticles can be used as probes molecules to detect the specific DNA sequences, many hybridization strategies can be used to design the microarray. We know that when the metallic nanoparticles immobilize on the metal surface, the SPR angle will changing with the type, number, and distribution of the nanoparticles. In another hand, the scatter and the absorption behavior of the nanoparticles will also changing with the situation describing above. That means if we plating metal on the glass substrates and use the metallic nanoparticle as our labeling method, we may read the same chip by two total different mechanisms, one is the scattered signals caused by the nanoparticles itself and the other is the reflected signals caused by the changing dielectric constant of effective medium. We attempt to design a new microarray system based on plasmon resonance, and propose a new array detecting structure that can read the information contained in a chip both through the SPR spectrum and the evanescent wave induced scatter.
(1).By transmission, we can get the spacial information that can used to perform the griddling in the following procedure.
(2).Through the prism coupling, we can get the reflected signal of the chip.
(3).Through the excitation of evanescent wave, we can get the scattered signal emitted from the metallic nanoparticles.
About the experimental method, the transmission signals can get from the scanner, the reflecting signals were obtained from the Kretschmann mode, and the investigations on scatter signals so far were performed by wave guide coupling method. About the preliminary achievement, we have successfully aligned the reflecting images by the scanned images, and can further integrate the streaming reflecting images into the integrated image. About the scattering signals experiment, we already can observe the evanescent wave induced scattering through the wave guide coupling method, under this structure, we can detect the scattered signal from the 14.6pM 40nm gold nanoparticles. Therefore the proposed structure of this thesis has been proved possible preliminarily. If the structure works, it may replace the conventional fluorescent labeling method and becomes a more sensitivity, reliable biochip platform. But the practical realization still needs more efforts to achieve.
Subjects
生物晶片
電漿共振
漸逝波
金屬奈米粒子
biochip
plasmon resonance
evanescent wave
metallic nanoparticle
Type
thesis