Novel high sensitivity SPR sensor based on surface plasmon resonance technology and IMI waveguide structure

Abstract

Surface plasmon resonance (SPR) technology features convenient and rapid detection and high sensitivity; it does not need to mark samples and can maintain molecular activity. In this study, we investigate the symmetrical IMI waveguide structure of glass–silver film–ethanol and realize the high sensitivity of the SPR sensor in a low-temperature environment. We determined the relationship between the change in ethanol temperature and SPR resonance angle via the relationship between the refractive index of the liquid sensing material and the ambient temperature. Results show that the SPR sensor transmittance is as high as 95%. As the temperature increases, the resonance angle of the new Kretschmann configuration decreases, which is suitable for low-thermal sensing. Changing the proportion of the ethanol solution structure has no effect on the resonance phenomenon. The sensitivity of the sensor reaches −0.408°/°C. The device can effectively improve the accuracy and anti-interference ability of the angle scanning SPR sensor and has good application and promotion value.