Electrochemical Method for Analysis of Cholesterol Based on In Situ Synthesized Graphene Decorated with Zinc Oxide Nanoparticles

Graphene decorated with zinc oxide nanoparticles were synthesized in a single step. Through this process zinc oxide nanoparticles were deposited onto graphene nanosheets. The nano-composites were characterized using X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), energy dispersive spectroscopy (EDX), cyclic voltammetry and electrochemical impedance spectroscopy. The nanocomposite material displayed excellent catalytic properties toward Cholesterol in combination with cholesterol oxidase (ChOx). The cholesterol detection limit was found to be 5.0 mu mol L-1 and a sensitivity 1.3 mu A/mu M cm(2) with linear correlation coefficient R-2 = 0.980. The Cholesterol oxidation also followed the Michaelis-Menten kinetics with apparent Km of 46.5 mu M (C) 2013 The Electrochemical Society. All rights reserved.