A New Route to Glucose Sensing Based on Surface Plasmon Resonance Using Polyindole

In the present study, we report the first polyindole-modified metal (Au) as a glucose sensor utilizing surface plasmon resonance (SPR) technique. Polyindole (PIn) was deposited by spin coating to modify the surface of the gold disk. Sensor surface was prepared by immobilizing glucose oxidase on the polyindole-modified gold disk. Different concentrations of glucose were taken to analyze the sensor response. A change in refractive index of the film was observed due to the chemical reactions of glucose with glucose oxidase. The response of the sensor is fast and highly sensitive to low concentrations of glucose and the sensitivity increases in the range of 0.075–0.5 μM. The use of Au/polyindole (PIn/Au) substrates for SPR-based study of bio-molecular sensing has been demonstrated.