Amperometric glucose biosensor based on NiFe2O4 nanoparticles and chitosan

A novel glucose biosensor was fabricated by integrating glucose oxidase (GOx) with chitosan/NiFe2O4 nanoparticles (CHIT/NiFe2O4NPs) on a glassy carbon electrode (GCE). The properties of CHIT/NiFe2O4NPs/GOx were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–vis spectroscopy, Fourier transform infrared spectroscopy (FTIR) and electrochemical impedance spectroscopy (EIS). The GCE modified with the CHIT/NiFe2O4NPs/GOx showed excellent electrocatalytical response to the oxidation of glucose when ferrocene carboxylic acid was used as an artificial redox mediator, which was studied by cyclic voltammetry (CV). Different parameters including GOx concentration, working potential and pH of supporting electrolyte that governed the analytical performance of the biosensor, have been studied in detail and optimized. The biosensor was applied to detect glucose with a linear range of 1 × 10−4–2.0 × 10−2 mol L−1. The biosensor exhibited excellent performance for glucose at applied potential of 0.6 V with a fast response time (<4 s).