NiO hedgehog-like nanostructures/Au/polyaniline nanofibers/reduced graphene oxide nanocomposite with electrocatalytic activity for non-enzymatic detection of glucose

A novel sensitive non-enzymatic glucose sensor was fabricated based on nickel oxide hedgehog-like nanostructures decorated ternary gold nanoparticles/polyaniline nanofibers/reduced graphene oxide nanocomposites (NiO/Au/PANI/rGO). The morphology and structure of NiO/Au/PANI/rGO nanocomposites were characterized by field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), Raman spectroscopy, and Fourier transform infrared (FT-IR). Electrochemical impedance spectroscopy (EIS) data also indicated the charge transfer of each layer decreased compared to the underneath layer. Electrocatalytic and electrochemical behavior of the modified electrode for the detection and measurement of glucose determined by cyclic voltammetry and amperometric methods. The results revealed that the NiO/Au/PANI/rGO nanocomposite modified glassy carbon electrode exhibited remarkable electrocatalytic performance toward glucose oxidation, with a wide linear range of 0.09–6 mM and a low detection limit of 0.23 μM based on a signal to noise ratio of 3. This electrode can effectively analyse glucose concentration in human serum samples, avoiding interference, and compared to the spectrophotometry method. Using the Student's t-test and F-test, there was no significant difference between the compared methods. Also this electrode is a promising non-enzymatic glucose sensor due to its fast response, good selectivity and stability and low overpotential.