Voltammetric determination of Auramine O with ZIF-67/Fe2O3/g-C3N4-modified electrode

Abstract

In the present work, the synthesis of ZIF-67/Fe₂O₃/g-C₃N₄ and its use for voltammetric determination of Auramine O are demonstrated. The resulting materials were characterized by means of X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, and nitrogen adsorption/desorption isotherm. The composite composes of polyhedron ZIF-67 particles evenly decorated with flocculent Fe₂O₃/g-C₃N₄ and has a specific surface area of 600 m².g^− 1. Cyclic voltammetry and differential pulse voltammetry were performed to investigate the electrochemical behavior of Auramine O at ZIF-67/Fe₂O₃/g-C₃N₄-modified electrode. An excellent linear relationship between the anodic peak current and Auramine O concentration was found in the range of 1.9–17 µM under the optimized experimental conditions. The proposed electrochemical method exhibits high repeatability with a low detection limit of 0.65 µM. This method was successfully employed to the determine Auramine O in pickled vegetable samples, showing excellent agreement with the results obtained from HPLC analysis.