Electrochemical Determination of Environmental Hormone Nonylphenol Based on Composite Film Modified Gold Electrode

In this paper, a novel electrochemical sensor based on thiol-beta-cyclodextrin (beta-CD-SH) and graphene (GR) hybrid-modified gold electrode (beta-CD-SH-GR/Au) was prepared by electrochemical reduction of thiol-beta-cyclodextrin-graphene oxide (beta-CD-SH-GO/Au). The composite of beta-CD-SH/GO was directly synthesized on the surface of Au electrode by electrochemical polymerization using the chrono amperometry, and then reducted by cyclic voltammetry (CV). Meanwhile, the electrochemical behavior of nonylphenol (NP) was studied by CV and differential pulse voltammetry (DPV). It was found that the oxidation current on beta-CD-SH-GR/Au electrode was much higher than on the Au, beta-CD-SH/Au and beta-CD-SH-GO/Au electrodes. The oxidation potential shifted negatively, indicating that the beta-CD-SH-GR/Au electrode had obviously catalytic activity on the oxidation of NP. Under the optimized conditions, the oxidation peak current exhibited a good linear relationship in the concentration range from 0.07 to 70 mu mol L-1 (R = 0.9952) and the detection limit was 0.061 mu mol L-1 (S/N = 3). The prepared electrode was successfully applied to the determination of NP with the recovery from 92.36% to 105.6%, showing a practical prospect in real samples. (C) 2015 The Electrochemical Society. All rights reserved.