Highly Sensitive Wavelength-Interrogating Prism-Based SPR Sensor With Fixed Angle Incidence

In the field of biosensing, a major innovation has been realized in this work: a wavelength-interrogating surface plasmon resonance (SPR) sensor incorporating a high-precision and high-resolution prism turntable system has been designed and constructed. The sensor not only retains the classical advantages of SPR sensors, such as high sensitivity, nonlabeling, real-time monitoring, and fast response, but also realizes a quantum leap in sensitivity at the critical incidence angle by introducing a unique prism coupling technique. The breakthrough of this research lies in the first experimental verification of the sensor’s sensitivity as high as 10 367 nm/RIU at an incidence angle of 52.8°, which is nearly five times higher than that of the conventional fiber-optic SPR sensors, marking a major breakthrough in the performance of SPR sensors. In addition, this study deeply explores the effect of the change of incidence angle on the sensor sensitivity, which provides a brand new thinking perspective for the traditional strategy of material to improve the sensitivity. Through both theoretical and experimental verification, this research not only opens up a new way for the development of SPR sensor technology but also predicts that this innovative system will have a widely application prospect in the field of biochemical detection.