Journal of Electroanalytical Chemistry, Vol.778, 103-109, 2016
Electrochemical oxidation of nimesulide in aqueous acid solutions based on TiO2 nanostructure modified electrode as a sensor
Cyclic voltammetric and differential pulse voltammetric technique were used to investigate the oxidation behavior of nimesulide in these studies. An effort was made to use TiO2 nanoparticles to modify the electrode surface to accentuate an effective technique for the determination of nimesulide. XRD and SEM investigation were carried out to understand the morphology of TiO2 nanoparticles. Electro-oxidation studies for bare glassy carbon electrode and TiO2 modified glassy carbon electrode shows an enhanced sensitivity for nanostructure-modified electrode. The electrode prepared was used to develop a sensible method for the trace determination of nimesulide. A wide linear range between 40 mu M-100 mu M with LOD and LOQ337 nM and 11.2 nM were observed respectively. Further, it was observed that, two protons and two electrons were involved in the reaction mechanism with an irreversible and diffusion controlled electrode process at pH 2. In addition, charge transfer coefficient, heterogeneous rate constant, were calculated. (C) 2016 Elsevier B.V. All rights reserved.
Keywords:Drug analysis;Heterogeneous rate constant;Nimesulide;Oxidation;Titanium dioxide nanoparticles