Nonenzymatic biosensor based on CuxO nanoparticles deposited on polypyrrole nanowires for improving detection range

CuxO (CuO and Cu2O composite) nanoparticles modified polypyrrole (PPy) nanowires were fabricated and used as a biosensor for detecting glucose (GLC). PPy nanowires were prepared through electrodeposition, while CuxO nanoparticles were deposited on PPy nanowires by electrodeposition and electrochemical oxidation in situ. The scanning electron microscopy images showed the CuxO nanoparticles aligned along the PPy nanowires uniformly and the average size of CuxO nanoparticles is about 90 nm. The electrocatalytic activity of CuxO/PPy/Au towards GLC was investigated under alkaline conditions using cyclic voltammetry and chronoamperometry. The sensor exhibited a linear range up to 8 mM of GLC, which is more than two times of most of the existing non-enzymatic GLC sensors based on CuO or Cu2O. The sensitivity of the sensor is 232.22 mu AmM(-1)cm(-2) and detection limit is 6.2 mu M (at signal/noise=3). Moreover, the sensor showed excellent selectivity, reproducibility and stability properties. These excellent performances make CuxO/PPy/Au a good nonenzymatic GLC sensor. (C) 2012 Elsevier B.V. All rights reserved.