Characterization of a self-assembled monolayer of thiol on a gold surface and the fabrication of a biosensor chip based on surface plasmon resonance for detecting anti-GAD antibody.
A biosensor chip utilizing surface plasmon resonance (SPR) was fabricated for detecting anti-glutamic acid decarboxylase (GAD) antibody, which is an indicator of the presence of type I diabetes mellitus. The sensor surfaces were constructed from various thiol mixtures of different molar ratios of 3-mercaptopropionic acid (3-MPA) to 11-mercaptoundecanoic acid (11-MUA). To determine the surface characteristics of the different alkanethiol monolayers, several quantitative and kinetic measurements were carried out. The extent of immobilization of streptavidin (SA) and biotin-GAD (the anti-GAD receptor) and the immune response of anti-GAD antibody against GAD were measured using the SPR biosensor. The terminal functional group of a thiol has different effects on the adsorption and covalent binding of protein depending on the steric hindrance. The protein chip described herein permits simple, rapid detection of anti-GAD antibody.
Lee
Jung Wook
JW
Department of Chemical Engineering, Sungkyunkwan University, Suwon 440-746, South Korea.
Sim
Sang Jun
SJ
Cho
Sung Min
SM
Lee
Jeewon
J
D000906:Antibodies / Q000032:analysis*; D005968:Glutamate Decarboxylase / Q000276:immunology*; D006046:Gold; D013438:Sulfhydryl Compounds; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D013997:Time Factors
D000906:Antibodies; D013438:Sulfhydryl Compounds; D006046:Gold; D005968:Glutamate Decarboxylase