Electrochemical determination of paclitaxel using a poly(3-nitro-L-tyrosine)/WC NPs modified gold electrode

Given critical therapeutic role and formulation challenges for paclitaxel, the accurate quantification of PAC in pharmaceutical products and biological samples is of great importance. In this study, we developed a novel electrochemical sensor by electropolymerizing 3-nitro tyrosine on a gold electrode, followed by modification with tungsten carbamide (WC) nanoparticles to enhance conductivity and surface area. Scanning electron microscopy confirmed a uniform nanostructured coating with high electroactive surface roughness. The fabricated P3NLT/WC/AuE sensor exhibited a distinct oxidation signal at −1.13 mV, which shifted positively upon interaction with PAC, indicating a selective recognition process between the polymeric layer and the drug. Using differential pulse voltammetry, the sensor displayed a broad linear dynamic range (1.33E-09 mol.L -1 to 5.42E-06 mol.L -1 ) and an ultra-low detection limit of 1.20E-11 mol.L -1 . The applicability of the developed platform was validated through the determination of PAC in commercial injection formulations, achieving recovery rates between 99.01% and 101.02%. These results highlight the P3NLT /WC/AuE sensor as a promising, sensitive, and selective analytical tool for pharmaceutical quality control and therapeutic drug monitoring of paclitaxel in clinical practice.