Glucose biosensor based on immobilization of glucose oxidase in poly(o-aminophenol) film on polypyrrole-Pt nanocomposite modified glassy carbon electrode

Novel Pt nanoclusters embedded polypyrrole nanowires (PPy-Pt) composite was electrosynthesized on a glassy carbon electrode, denoted as PPyPt/GCE. A glucose biosensor was further fabricated based on immobilization of glucose oxidase (GOD) in an electropolymerized. non-conducting poly(o-aminophenol) (POAP) film that was deposited on the PP`y-Pt/GCE. The morphologies of the PPy nanowires and PPy-Pt nanocomposite were characterized by field emission scanning electron microscope (FE-SEM). Effect of experimental conditions involving the cycle numbers for POAP deposition and Pt nanoclusters deposition, applied potential used in glucose determination, temperature and pH value of the detection solution were investigated for optimization. The biosensor exhibited an excellent current response to glucose over a wide linear range from 1.5 x 10(-6) to 1.3 x 10(-2) M (r = 0.9982) with a detection limit of 4.5 x 10(-7) M (s/n = 3). Based on the combination of permselectivity of the POAP and the PPy films, the sensor had good anti-interference ability to ascorbic acid (AA), uric acid (UA) and acetaminophen. The apparent Michaelis-Menten constant (K) and the maximum current density (I.) were estimated to be 23.9 mM and 378 mu A/cm(2) respectively. In addition, the biosensor had also good sensitivity, stability and reproducibility. (c) 2006 Elsevier B.V. All rights reserved.