Advanced electrochemical sensor based on nickel sulfide-tungsten carbide nanocomposite for trace detection of chlorpromazine in animal-based foods.

Detection of unauthorized drug residues in animal-derived foods is essential due to associated health risks. Chlorpromazine (CPZ), a toxic antipsychotic drug occasionally misused in livestock, necessitates sensitive detection techniques. This study introduces an electrochemical sensor utilizing a glassy carbon electrode modified with a nickel sulfide‑tungsten carbide (NiS/WC) nanocomposite. The composite was synthesized via hydrothermal methods and characterized using XRD, FT-IR, SEM, and XPS, confirming its structure and surface properties. Electrochemical evaluation through cyclic and differential pulse voltammetry demonstrated improved electron transfer and catalytic efficiency. The sensor achieved a broad linear detection range (0.027-2940 μM) with a low detection limit of 14.8 nM for CPZ. It showed excellent repeatability (RSD < 2%), selectivity against common interferents, and high operational stability. Application to real meat samples yielded high recovery rates, indicating strong practical potential. This sensor provides a reliable, sensitive platform for CPZ detection in food safety monitoring.