Low-cost electrochemical sensor based on montmorillonite for antibiotic tetracycline hydrochloride detection

Tetracycline hydrochloride (TC(HCl)) has been extensively used as veterinary drugs and food additives in feed, but the abuse of TC(HCl) poses a great threat to the ecological environment and human health. In this paper, TC(HCl) in aqueous solution was successfully probed by an iron cation exchanged montmorillonite modified glassy carbon electrode (Fe-Mt/GCE) via a direct voltametric method. The electrochemical response sensitivity of Fe-Mt-150/GCE is 27.1 µA µM−1 cm−2. Compared with the traditional electrode, the Fe-Mt/GCE exhibits higher response current intensity in the rapid scanning process, which should be contributed to the larger surface area and more active sites of the modified electrode for the oxidation reaction of TC(HCl). Additionally, it is found that higher scanning corresponds to better signal, implying there are enough active sites in Fe-Mt/GCE for TC(HCl) detection. The machine learning method was further employed to explore the optimum parameters. The predicted data are highly consistent with the experimental data, which were verified by the testing phase in machine learning. The application of machine learning to describe and summarize the data may bring new ideas to the future researches. Montmorillonite could be potentially applied as an electrochemical sensor for antibiotic tetracycline hydrochloride detection due to its low cost and easy fabrication.