Prickly nickel nanowires grown on Cu substrate as a supersensitive enzyme-free electrochemical glucose sensor

Abstract

A novel and supersensitive enzyme-free electrochemical glucose sensor fabricated on copper substrate by in situ growing three-dimensional (3D) prickly nickel nanowires (PNNWs) using an electroless strategy is explained for the first time. The surface morphology of PNNWs is characterized by field emission scanning electron microscopy (FESEM) and energy dispersive X-ray diffraction (EDX) microanalysis. Electrochemical performance of the Cu-Ni-PNNWs electrode for sensing of glucose is investigated by cyclic voltammetry and chronoamperometry in alkaline solutions. The Cu-Ni-PNNWs electrode showed a great enhanced electrocatalytic activity toward oxidation of glucose, in comparison with its platform, Cu-Ni, prepared by electrodeposition of Ni on Cu electrode. Under optimized conditions, the sensor showed a linear response in a wide range of glucose concentrations, from 3.0×10−6 to 2.0×10−3M, with a large sensitivity (4243μAcm−2mM−1) and low detection limit of 0.1μM. The sensor is 1.5 times more sensitive than the recently reported (2900μAcm−2mM−1) for nonenzymatic detection of glucose using porous nickel nanostructures. In addition, the Cu-Ni-PNNWs electrode is successfully tested for determination of glucose in human blood sample. The experimental results revealed a good reproducibility, long-term stability and high selectivity with no interference from other oxidizable species accompanying glucose in matrix of the real samples.