Chitosan/polyaniline/graphene oxide-ferrocene thin film and highly-sensitive surface plasmon sensor for glucose detection

This work aims to develop a surface plasmon resonance (SPR) sensor based on Chitosan/Polyaniline/Graphene oxide-Ferrocene (CS/PANI/GOFc) composite thin film for glucose detection. The optimum formulation of the composite has been calculated from experimental refractive index data and using the effective medium theory (EMT). Then, the optimum composite, CS 25%/PANI 25%/GOFc 50%, has been prepared and evaluated in the design of the glucose sensor via modification of the SPR gold chip. Results demonstrate that the linear response of the SPR sensor is in the range of 0.5–100 µM of glucose with a sensitivity of 0.0202° μM−1. The Langmuir and Sips models have been used to analyze the binding affinity, which represents a higher affinity constant for the composite film compared to the bare gold chip.