Glucose biosensor electrode fabrication based on CuO /ZnO nanostructures

Abstract

Abstract Zinc oxide nanowires (ZnO NWs) were successfully synthesized by Zn-metal evaporation and deposition of a thin metal film about 20 µm on quartz substrates. Followed by the subsequent oxidation process in the air at 550 oC for 4h. Copper oxide nanoparticles (CuO NPs) were then deposited on ZnO NWs, using the drop-casting technique. The crystal structure and morphology of ZnO nanowires were investigated by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results of XRD confirmed that the ZnO has the Wurtizite polycrystalline structure along [101] direction. The SEM images revealed that the highest density of ZnO nanowires was distributed over a large area of the substrate with many wrinkles. The current response to glucose of the CuO/ZnO/Qz electrode gives a linear dependence range from 50 µM to 500 µM of glucose. The typical sample of CuO/ZnO NWs was used for a glucose biosensor electrode. It was found that CuO NPs layer on ZnO NWs has well improved the performance of the electrode and increased the electrocatalytic ability towards glucose oxidation.