Enhanced performance of a surface plasmon resonance immunosensor for detecting Ab-GAD antibody based on the modified self-assembled monolayers.
To enhance the feasibility of surface plasmon resonance (SPR) immunosensor as a tool for diagnosing type I diabetes, we enhanced the sensitivity of immunoresponse for detecting the monoclonal anti-glutamic acid decarboxylase (GAD) antibody by modification of mixed self-assembled monolayers (SAMs). The effects of the different mixed SAMs were evaluated with respect to the degree of streptavidin immobilization, the degree of biotin-GAD immobilization, and the immunoresponse sensitivity. Consequently, the sensitivity of the immunoresponse for the detection of anti-GAD antibody was enhanced as a result of the reduction in steric hindrance brought about by using SAMs of heterogeneous lengths. The immunoresponse for detecting the monoclonal anti-GAD antibody was also enhanced with the reduction of the excess immobilization of biotin-GAD and the minimization of non-specific binding that resulted from the simple substitution of the spacer from a carboxylic-terminated SAM for the hydroxyl-terminated SAM.
Choi
Sue Hyung
SH
Department of Chemical Engineering, Sungkyunkwan University, 300 Chunchun-dong, Chanan-Gu, Suwon 440-746, South Korea.
Lee
Jung Wook
JW
Sim
Sang Jun
SJ
D000906:Antibodies / Q000032:analysis / Q000276:immunology; D015415:Biomarkers / Q000032:analysis; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D020099:Coated Materials, Biocompatible / Q000032:analysis / Q000737:chemistry; D003460:Crystallization / Q000379:methods; D003922:Diabetes Mellitus, Type 1 / Q000175:diagnosis / Q000276:immunology; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005968:Glutamate Decarboxylase / Q000032:analysis* / Q000276:immunology*; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation* / Q000379:methods; D020349:Surface Plasmon Resonance / Q000295:instrumentation* / Q000379:methods
D000906:Antibodies; D015415:Biomarkers; D020099:Coated Materials, Biocompatible; D005968:Glutamate Decarboxylase