关键词: 表面等离子体共振技术, 免疫传感器, 放大检测, 链霉亲和素-生物素化抗体复合物

Abstract: Surface plasmon resonance(SPR)immunosensor is a relatively new immunoassay technique and has been receiving more and more attention in recent years. However, a major disadvantage of SPR for bioanalytical applications is that low concentration or low molecular mass analytes could not be detected directly. Therefore, it is a challenging task to develop strategies for improving the detection limit/sensitivity of SPR. In this paper, authors present a novel strategy for improving the sensitivity of SPR immunosensing using streptavidin-biotinylated antibody complex. It is proven that the amplification strategy causes a dramatic improvement of the detection sensitivity. This amplification strategy is based on the construction of a molecular complex between streptavidin and biotin labeled protein. The complex can be formed in a crosslinking network of molecules so that the amplification of response signal will be realized due to the big molecular size of complex.

Key words: surface plasmon resonance technique, immunosensor, amplified assay, streptavidin-biotinylated antibody complex