A sensitive non-enzymatic glucose sensor in alkaline media based on Cu/MnO2-modified glassy carbon electrode

A novel and simple glucose sensor based on layer-by-layer (LBL) assembly of Cu and MnO2 nanoparticles on the glassy carbon electrode (Cu/MnO2/GCE) was constructed. The morphology and composition of the Cu and Cu/MnO2 on the electrode surface were observed by scanning electron microscopy and X-ray diffraction. Electrochemical experiments showed that the proposed Cu/MnO2/GCE exhibited excellent electrocatalytic properties to glucose. The oxidation peak currents of glucose on the Cu/MnO2/GCE were linearly related to glucose concentration in a wider linearity range from 0.25 mu M to 1.02 mM with a correlation coefficient of 0.9977. The sensitivity and detection limit was 26.96 mu A mM(-1) and 0.1 mu M (S/N = 3), respectively. The Cu/MnO2 nanocomposite-modified electrode presented attractive features such as high sensitivity, stability, reproducibility, and interference-free property. The applicability of the proposed method to the determination of glucose in serum samples was demonstrated with satisfactory results.