First report on green electrochemical sensing of bepotastine besilate based on tungsten doped vanadium dioxide nanoparticles: DFT assisted mechanistic insight

A pioneering green electroanalytical sensor was introduced for a precise and environmentally considerate quantification of bepotastine besilate (BPST); a second-generation antihistaminic drug for treating allergic rhinitis and pruritus. The surface morphology and the electrochemical behavior of the tungsten-doped vanadium dioxide nanoparticles based screen printed sensors (W–VO₂NPs-SPCEs) were fully characterized by SEM, EDX, cyclic voltammetry (CV), and electrochemical impedimetric spectroscopic measurements (EIS). The developed sensors showed enhanced performance against BPST in BR-buffer at pH 5 within the linear dynamic concentration range from 0.02 to 3.65 µg mL −1 , and LOD value 0.006 µg mL −1 . Deep and comprehensive molecular orbital and electroanalytical studies suggested oxidation of the piperidine nitrogen atom (N13) through the transfer of one proton/two-electrons mechanism. The W–VO₂NPs-SPCEs exhibited high mechanical stability, measurement reproducibility, prolonged storage lifetime, and adequate selectivity against BPST. Based on the enhanced sensitivity and selectivity of the W–VO₂NPs based sensors, BPST residues were monitored in the marketed pharmaceutical tablets, ophthalmic formulation, and synthetic aqueous humor liquid samples. The degradation behavior and dissolution profile of bepotastine in pharmaceutical tablets were also reported.