A facile and sensitive electrochemical sensor for non-enzymatic glucose detection based on three-dimensional flexible...

A novel three-dimensional nickel hydroxide/polyurethane (Ni(OH)₂/PU) electrode was prepared by a simple and environmentally friendly method and used for non-enzymatic detection of glucose. The Ni(OH)₂/PU electrode was obtained by one-pot hydrothermal method of loading nickel hydroxide on a cheap, easily available and flexible polyurethane sponge, which is facile and energy-saving. The porous structure of the polyurethane sponge provides a large surface area and a rich electrochemical active site for the electrode, which is beneficial to the oxidation reaction of glucose on the surface of the electrode with Ni(OH)₂. The Ni(OH)₂/PU electrode structure was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The cyclic voltammetry test was used to study the catalytic performance of Ni(OH)₂/PU electrode for oxidation of glucose and the chronoamperometry was used to investigate the detection performance of Ni(OH)₂/PU electrode on glucose. The results indicate that this non-enzymatic glucose sensor had a high sensitivity of 2845 μA mM^-1 cm^-2, a low detection limit of 0.32 μM (S/N = 3), a detection range of 0.01-2.06 mM and response time of less than 5 s. In addition, the Ni(OH)₂/PU electrode had excellent selectivity, reproducibility and stability and also exhibited effective detection of glucose in fetal bovine serum (FBS). In summary, Ni(OH)₂/PU electrode had broad prospects as an excellent candidate for non-enzymatic glucose sensors. The study also opens up a facile and energy-saving approach for preparing three-dimensional (3D) functionalized polymer electrode via hydrothermal method as electrochemical sensors.