Ultra-trace detection of sulfathiazole, an anti-infective agent and environmental contaminant, using electrochemical sensing with holmium vanadate-graphene oxide nanocomposites

Abstract

BackgroundThe study elucidates the electrochemical capabilities of a newly synthesized nanocomposite, constituting Holmium Vanadate (HV) shielded by Graphene Oxide (GO), targeted at the ultra-sensitive detection of Sulfathiazole (STA), a prevalent antibiotic and environmental pollutant. This innovation stands as a significant stride in environmental nanotechnology, addressing the critical need for precise pollutant monitoring tools. MethodsA hydrothermal technique facilitated the synthesis of the HV@GO nanocomposite, which was subsequently subjected to detailed electrochemical characterization to uncover its intrinsic properties. The redox current responses of Glassy Carbon Electrodes (GCE), in varied configurations including GO/GCE and HV/GCE, were meticulously analyzed through cyclic voltammetry (CV) experiments. Further, a calibrated analysis, integrating both CV and amperometric techniques, was employed to establish optimal conditions for STA detection, encapsulating key parameters like concentration, pH, and scan rate. The analysis was extended to real-world contexts, evaluating the performance of the sensor in river water and urine samples spiked with STA. Significant FindingsThe HV@GO/GCE displayed marked electrocatalytic activity, demonstrating an augmented redox peak current and a notable peak potential separation, thereby establishing itself as a potent tool for STA detection. Impressively, it achieved a low detection limit of 2.94 nM, manifesting both high sensitivity and stability. Additionally, the sensor showcased remarkable resistance to potential interfering substances, indicating its robust applicability in complex environmental matrices. The preliminary tests affirm the sensor's efficacy in ultra-sensitive STA detection, proposing a promising pathway for the monitoring of drug pollutants in various environmental mediums.