Bird nest-like zinc oxide nanostructures for sensitive electrochemical glucose biosensor

Abstract

In this research, a novel bird nest-like zinc oxide (BN-ZnO) nanostructures were prepared by a simple solvothermal method. A sensitive electrochemical glucose biosensor was for the first time developed based on the immobilization of glucose oxidase (GOx) on nanostructured BN-ZnO modified electrode. The BN-ZnO nanostructure and the resultant biosensor were characterized by scanning electron microscope, X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy, and electrochemical impedance spectroscopy. BN-ZnO nanostructures have large specific surface area and can load large amounts of GOx molecules. Meanwhile, BN-ZnO provides an excellent microenvironment to retain the native bioactivity of enzymes and to promote direct electron transfer between GOx and electrode surface. The proposed biosensor shows a wide linear range of 0.005–1.6 mmol/L, high sensitivity of 15.6 mA L mol−1 cm−2 with a low detection limit of 0.004 mmol/L. The resulting biosensor also shows excellent selectivity, acceptable stability and reproducibility, and can be successfully applied in the detection of glucose in human serum samples at −0.37 V.