Electrochemical Sensing of Nitrofurazone and Semicarbazide on an Au-Ag Film Fabricating from a Deep Eutectic Solvent

A facile electrochemical sensor is reported for the highly selective and sensitive detection of nitrofurazone (NFZ) and its metabolites, semicarbazide (SC), by using an Au-Ag modified electrode. The Au-Ag film was produced on a Cu foil by electrodeposition in a choline chloride-urea-glycerol ternary deep eutectic solvent containing gold (III) ions and silver (I) ions. Cyclic voltammetry (CV) indicates that the co-deposition of Au-Ag would be feasible. The morphology, crystallinity, and composition of Au-Ag deposits were characterized via scanning electron microscopy (SEM), powder X-ray diffractometer, and X-ray photoelectron spectroscopy (XPS). Under the optimal condition, the Au-Ag modified electrode shows a wider linear concentration range of 1.99–643.49 μ M with a low detection limit of 0.2 μ M for NFZ. The corresponding linear range of SC is 7.94 to 482 μ M, and the detection limit is 1.01 μ M. It also demonstrated good anti-interference ability against various common interfering substances. Finally, the modified electrode was successfully applied in the real samples, and the average recoveries for NFZ and SC were 100.59% and 101.01%, respectively. The present electrochemical strategy is promising to broaden the practical electrochemical application in the environment.