Pioneer electrochemical approach for the determination of Metaxalone in biomedical and environmental samples using W: TiO₂/S-GCN@CPE sensor

This study focuses on developing a rapid, easy-to-use, and sensitive sensor for the electroanalytical detection of Metaxalone (MXL) for the first time. A novel sensor was created by combining sulfur-incorporated graphitic carbon nitride (S-GCN) with tungsten-doped titanium oxide nanoparticles (W: TiO₂ NPs) in a carbon paste, which was then loaded into a polytetrafluoroethylene (PTFE) tube. The synthesized modifiers were characterized using SEM, XRD, and FTIR techniques to understand their structural, morphological, and functional features, contributing to the electrocatalytic activity of the modified sensor (W: TiO₂/S-GCN@CPE). Comparative analysis showed that W: TiO₂/S-GCN@CPE achieved higher detection currents than the unmodified carbon paste electrode (CPE). Cyclic voltammetry (CV) and square wave voltammetry (SWV) were used to detect and quantify MXL electrochemically. The electrode's physicochemical properties were studied under optimal conditions within a potential range of 0.3 V to 1.5 V. The W: TiO₂/S-GCN@CPE showed a detection limit of 0.85 x 10^-8 M and demonstrated linearity over a concentration range of 0.1–100 x 10^-7 M. The sensor's selectivity against interference from metal ions was also assessed. In practical applications, the developed electrode effectively detected MXL in spiked water, tablets, and biological samples, showing significant detection capacity and good recovery rates. Additionally, the electrode demonstrated stability across multiple measurements, positioning W: TiO₂/S-GCN@CPE as a promising sensor for MXL detection.