[Oriented immobilization of human IgG by protein A on imaging ellipsometry biosensor].
The biosensor based on optical imaging ellipsometry, can be used to detect directly, without labeling, the surface concentration of biomolecules on solid surface. The feasibility of using protein A to immobilize antibody on the silicon surface of the imaging ellipsometry biosensor was investigated in this study. The results showed that the anti-IgG immobilized by the protein A on silicon surface could bind effectively human IgG, and the human IgG immobilized on silicon surface by protein A bound more polyclonal antibody molecules than that immobilized on silicon surface directly, suggesting that protein A might block the surface to prevent the absorption of human IgG on surface directly, which might compromise its native configuration. The silicon surface modified with protein A is expected to be used to immobilize a variety of antibodies, as protein A can bind selectively the Fc regions of many mammalian IgG. The combination of imaging ellipsometry and the protein A surface modification has the potential to be developed into immunoassays of high sensitivity.
Meng
Yan-Li
YL
National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080, China.
Wang
Zhan-Hui
ZH
Jin
Gang
G
D015374:Biosensing Techniques / Q000379:methods*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D007074:Immunoglobulin G / Q000737:chemistry*; D013205:Staphylococcal Protein A / Q000737:chemistry*
D007074:Immunoglobulin G; D013205:Staphylococcal Protein A