Biocompatibility and Conductometric Property of Sol-Gel Derived ZnO/PVP Nanocomposite Biosensor Film

Nanocrystalline ZnO and ZnO/PVP nanocomposite films have been prepared by the sol-gel dip-coating technique from zinc acetate precursor on silicon wafer and Pyrex glass substrates. The films were characterized using atomic force microscopy for morphology, and X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy for chemical analysis. Thermally untreated and annealed films were studied in order to analyze the influence of temperature on the formation and properties of the films. The films have a uniform void-free surface and the grain size increases with the annealing temperature. The cell viability assays indicate that the growth rate of BPH cells incubated in the presence of ZnO was significantly reduced (35% of the control) compared to that of untreated controls, indicating antibacterial activity of ZnO as a result of the generation of hydrogen peroxide. The sensor characteristic of ZnO/PVP nanocomposite was also demonstrated by measuring the change in conductivity upon exposure to superoxide anion radical.