Carbon black-integrated tungsten disulfide nanohybrid for the electrochemical quantification of propyl gallate in food safety monitoring

The use of food-grade antioxidants remains characteristically challenging owing to their potential adverse effects and substandard quantification practices. In addition, detection and quantification of propyl gallate in food matrices poses significant risks to human health and environment are adequately adhered to. This novel study implements a new approach on using tungsten disulfide (WS₂) and carbon black (CB) nanocomposite to develop an electrochemical sensor for detecting propyl gallate at low concentration levels. The sensor's functionality was assessed using cyclic voltammetry and differential pulse voltammetry. Its performance was assessed for sensitivity, stability, repeatability, and practical application on real samples. The WS₂@CB-coated glassy carbon electrode (WS₂@CB/GCE) demonstrates excellent performance with broad linear detection range of 0.02–550 μM and a very low limit of detection at 7 nM. Moreover, the sensor was found to maintain 95.64 % of initial current response after 1 month, showcasing remarkable stability, repeatability (RSD: 1.08 %), reproducibility (RSD: 0.8 %), and overall stability (RSD: 2.5 %) when evaluated using standard repeated measurements. Analysis of real samples from food matrices, which are cooking oils and peanut butter, were found to have notable recovery percentages of 95.0 %–98.0 % and 96.0 %–99.0 % respectively, verifying the sensors' reliability for practical use.