Spr Characteristics Of The Complex Refractive Index Measurement

Surface Plasmon Resonance (SPR) sensor has attracted ever increasing research interest for it's very sensitive to refractive index changes of medium, and it has great application potential in many fields, such as biologyy, chemistry, medicine and many other fields. In this paper, two different coupling of SPR sensor structure was studied based on the principle of SPR.After deeply discussed the principle of SPR phase-interrogation with prism coupling for testing the complex refractive index, relative experimental setup was designed and established. We used deionized water and ethanol as a standard sample to verify our experiments, and measured the complex refractive index of 20% Intralipid^TM and fresh leporine blood, whose results had a good consistency with the data obtained using other methods. Therefore SPR-phase modulation technology is expected to become a new way to test complex refractive index of biological tissue, which will have some application value in future.SPR based on metallic periodic structures can improve the characteristic of SPR sensor. The plane-wave expansion transfer-matrix method and finite element method were carried out to simulate the transmission of metallic periodic structure SPR. The simulation results showed that the periodic SPR has a higher resolving power and a better noise-resistance ability. In addition, the structure parameters of the periodic structures are optimized in order to obtain better characteristics of the sensor.The complex refractive index measurement of biological tissues with SPR phase-interrogation and research for SPR periodic structure are both the groping works now, which will has reference value for extending its applying field and improving its characteristic.