Observation of Glucose Concentration in Water using Surface Plasmon Resonance

A surface plasmon resonance (SPR)-based biosensor in the Kretschmann configuration is used to detect glucose concentration. Here, we use SPR sensor, both experimentally and in simulation, for refractive index sensing where glucose solution of various concentrations is chosen as model. For the experiment part, the varied glucose concentrations were injected into a small reaction chamber encapsulating the non-functionalized thin gold (Au) SPR film, where the reflectivity and resonance angle changes were monitored in real-time. Finite Difference Time Domain (FDTD) was conducted to simulate the plasmon resonance modulation under various concentration dependent refractive indices. As the sensing descriptors, we utilized resonance angle and half width at half maximum (HWHM). As a result, both resonance angle and HWHM increase linearly to glucose concentration.