Non-enzymatic detection of Glucose using a capacitive nanobiosensor based on PVA capped CuO synthesized via co-precipitation route

Here, we report the fabrication and application of a novel capacitive nanobiosensor for the non-enzymatic detection of glucose. Polyvinyl alcohol capped copper oxide (PVA-CuO) nanoparticles were used for the non-enzymatic detection of glucose. PVA-CuO nanoparticles were synthesized using the co-precipitation method. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), contact angle and transmission electron microscopy (TEM) studies were performed to study the phase, crystallinity, shape, wettability and morphology of the prepared nanoparticles. Capacitance measurements were carried out for the detection of glucose, repeatability and reproducibility using impedance analyzer. Also, interference study was performed to see the specificity of the capacitive biosensor towards glucose detection. These results were further confirmed by electrochemical measurement (frequency response analysis). XRD study confirmed the monoclinic structure of the CuO without any impurities and average crystallite size obtained is 12 nm. FE-SEM study showed nearly rod-like nanostructure of the PVA-CuO. The contact angle study confirmed the hydrophilic nature of PVA-CuO with a contact angle of 57°. TEM study confirmed the nanocrystalline nature of the material and nearly rod-like structures. Capacitance study showed a decrease in capacitance with the increase in glucose concentration. The PVA-CuO film showed similar currents in the reproducibility and repeatability studies. The interference study was performed for common interfering agents and confirmed the high specificity of the prepared capacitive biosensor towards the glucose. These results were further confirmed by frequency response analysis.