Construction of a dual-signal molecularly imprinted photoelectrochemical sensor based on bias potential control for selective sensing of tetracycline

Abstract

The abuse of tetracycline antibiotics can lead to excessive environmental and food residues, causing allergic reactions that endanger health. Therefore, it is important to develop a sensitive method for sensing tetracyclines. Herein, a dual-signal molecularly imprinted photoelectrochemical sensor based on Au/ZnIn₂S₄ was created for the trace determination of tetracycline hydrochloride in water and milk. The anodic and cathodic photocurrents can be generated by controlling the bias potential of ZnIn₂S₄. The deposition of Au nanoparticles on ZnIn₂S₄ enhanced the absorption of visible light, facilitating carrier migration to enhance the photocurrent signal. The two independent signals do not interfere with each other, and validate each other to improve the confidence of the detection results. Combined with the specific recognition ability of molecular imprinting technology, the constructed sensor can detect tetracycline in the range of 1–500000 nM for both anode and cathode under optimal conditions, with the detection limit of 0.82 nM for the anode and 0.67 nM for the cathode. In addition, the sensor has satisfactory performance in actual samples and has some application prospects in antibiotic video detection.