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

Abstract

In this paper, a novel electrochemical sensor based on thiol-β-cyclodextrin (β-CD-SH) and graphene (GR) hybrid-modified gold electrode (β-CD-SH—GR/Au) was prepared by electrochemical reduction of thiol-β-cyclodextrin-graphene oxide (β-CD-SH—GO/Au). The composite of β-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 β-CD-SH—GR/Au electrode was much higher than on the Au, β-CD-SH/Au and β-CD-SH—GO/Au electrodes. The oxidation potential shifted negatively, indicating that the β-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 μmol L−1 (R = 0.9952) and the detection limit was 0.061 μmol 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.