A nonenzymatic amperometric glucose sensor based on three dimensional nanostructure gold electrode

A nonenzymatic amperometric glucose sensor was established based on the electrocatalytic oxidation of nanoporous gold (NPG) toward glucose. The NPG electrode was prepared by a facile, rapid one-step square-wave oxidation reduction cycle (SWORC) within 5 min. The prepared NPG electrode had high roughness, excellent electrocatalytic activity toward glucose electrooxidation and was characterized by scan electron microscopy (SEM), atomic force microscope (AFM) and cyclic voltammetry (CV). The CV was also used to evaluate the electrochemical response of the NPG electrode to the glucose oxidation in 0.01 mol L−1 NaOH solution. Under the optimal conditions, the NPG electrode showed a good linear relationship between the current response signal and the glucose concentrations in a range from 2 μmol L−1 to 1.375 mmol L−1 and 1.375 mmol L−1 to 15 mmol L−1 with a detection limit of 0.5 μmol L−1 (S/N = 3). In addition, the nafion was selected as the protective film to enhance specificity of the developed glucose biosensor, and the physiological levels of ascorbic acid (0.1 mmol L−1) and uric acid (0.02 mmol L−1) only had negligible interferences to the glucose detection. This new glucose sensor exhibited a fast amperometric response, high sensitivity and selectivity, and it was successfully used to detect the glucose in human serum sample with a satisfactory result.