Perfection And Optimization Of An Angle-scanning SPR Sensor System

Surface plasmon resonance (SPR) is a type physical optical phenomenon. It use evanescent wave as a probe to detect the optical variety of medium surface. Since the SPR sensor technology was used in the field of biochemical sensors, it obtained wide attention in the scientific community and commercial institutions due to its excellent sensitivity and real-time response characteristics. It has become the international research focus in the field of chemical detection, and has been gradually applied in the field of proteomics, drug screening and development, food safety, and clinical diagnosis.In this paper, the research status of SPR sensors and its application field is introduced at first. Then, the working mechanism and detection principle of surface plasmon wave (SPW) and surface plasmon resonance (SPR) are analyzed, and the prism type SPR sensor of Kretchsrnann structure is emphatically discussed. Matlab software is used to simulate and analyze several main factors affect SPR, which provides the basis for the selection of suitable SPR components. Based on the previous research, improvement and integration of the software and hardware are implemented, and some modules such as sampling system are added. A pump, which velocity can be adjusted, and a small sample pool are designed. The STC12C5410AD microcontroller is used to control the peristaltic pump for sampling. Controlling circuit of the goniometer is optimized for stable working and these electric circuits are integrated on a PCB. VC++ software programming is used to realize the integration of the control interface. By using this interface, the detection signals can be displayed and stored in real time, and goniometer and peristaltic pump can be controlled at the same time.This home-made SPR sensor and the experimental platform are used to measure air, water and glucose solution. Results show that with the increase of refractive index the location of the resonance angle also increases gradually, and the instrument has good repeatability and stability.