Numerical Modeling on Anodic Chronopotentiometric Transients for the Electrochemical Sensing of Methyl Salicylate

A novel electrochemical sensing methodology for the detection of methyl salicylate concentration, [MeS] through chronopotentiometric transients under galvanostatic mode is devised. The oxidation potential shifted cathodically, with the increase in [MeS] due to the reduction in absolute anodic current density. Either if anodic current density (ia) is lowered or [MeS] is enhanced, then the rate of oxidation is prevailed by diffusion control rather than charge-transfer limitations. The determined exchange current density was 7.9 × 10–4 A dm–2. Discrete anodic oxidation current was estimated and is about 8.49 mA in the potential range 493 to 606 mV. I order chronopotentiometric transients are having comparatively larger (0.005 Volt min.–1) and positive than the subsequent higher order transients at [MeS] = 7 mM and at ia = 0.063 Adm–2. The lower detection limit of 7 mM can be achieved with an absolute error 0.005. Off mode potential decay depends on [MeS] and ia. The anodic oxidation of salicylate di-ion occurs through three electrons transfer whereas methoxide ion takes place through one electron transfer. Diclofenac shifts the anodic potential more negatively, even at low concentrations. Nonlinear numerical simulations, to interpose anodic potential with [MeS] were carried out using MATLAB®.