Enhanced surface plasmon resonance immunosensing using a streptavidin-biotinylated protein complex

In this paper, we present a novel strategy for improving the sensitivity of surface plasmon resonance immunosensing using a streptavidin-biotinylated protein complex. 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 cross-linking network of molecules so that the amplification of the response signal will be realized due to the big molecular size of the complex. The results show that the amplification strategy causes a dramatic improvement of the detection sensitivity. hIgG protein could be detected in the range of 0.005-10 mug ml(-1).