The use of an electrode modified by polyvinylpyrrolidone film with a gold deposit for voltammetric determination of tetracycline in milk

Abstract

© 2019 Kazan Federal University. All Rights Reserved. Gold deposit immobilized on the surface of glassy carbon electrodes (GCE) and included in the polymer film of polyvinylpyrrolidone (Au-PVPr) shows electrocatalytic properties toward tetracycline oxidation. The catalytic effect observed at the GCE modified by gold deposit is expressed in a multiple increase of the current of antibiotic oxidation and in a decrease of the potential on 250 mV in comparison with the GCE. A two-fold increase in the oxidation current of tetracycline has been recorded on the GCE coated by the PVPr film with gold deposit (Au-PVPr-GCE) in comparison with its oxidation at the Au-GCE. The working conditions for the immobilization of the Au-PVPr composite on the GCE have been found. A method for voltammetric determination of tetracycline on the Au-PVPr-GCE has been proposed. Linear dependence of the current at this electrode on the tetracycline concentration has been observed in the range from 1·10–7 to 1·10–3 mol·L–1. The developed voltammetric method has been tested in determination of the tetracycline content in milk.