High-sensitivity bioinformation acquisition based on SPR biosensor
Xiaofeng Rong , Fangfang Liu, Yan Deng, Xinglong Yu (Department of Precision Instrument and Mechanology,TsinghuaUniversity,Beijing 100084,China)
High sensitivity of surface plasmon resonance (SPR) detection is of vital importance for expanding it’s application . It refers to sensing chip, light path, signal acquisition system and signal processing. Sensing chip, signal acquisition and signal processing are the most important factors. Sensitivity of the signal acquisition system is acquired, through analysing the SPR spatial phase modulation micro-array detecting system and SPR light intensity micro-array detecting system in this article. Detailed dependency of system sensitivity on photodetector is also analyzed based on light intensity and phase detection, and the measure of properly choosing and designing signal acquisition system is put forward. Results show that the sensitivity and resolution of phase detection is higher than that of light intensity detection. And light detection could achieve the same resolution level as 10-4 RIU, while phase detection could achieve the same resolution level as 10-6 RIU.