Simple and highly sensitive assay of axitinib in dosage form and biological samples and its electrochemical behavior on the boron-doped diamond and glassy carbon electrodes

Abstract

Abstract Axitinib, which is a potent and highly selective inhibitor, differs from previously used drugs by its higher activity potential of inhibition of vascular endothelial growth factor receptor tyrosine kinase. The sensitive, time-saving, and environmentally friendly voltammetric methods were developed, for the first time, for the quantification of axitinib using glassy carbon and boron-doped diamond electrodes. The effect of the pH, supporting electrolyte, and scan rate on the peak current and potentials of axitinib were studied for both electrodes. Using cyclic voltammetry, two irreversible anodic peaks, Ep1 and Ep2, were observed at 1.10 V and 1.22 V for glassy carbon, 1.15 V, and 1.30 V for boron-doped diamond electrodes, respectively, in 0.1 M sulfuric acid. By cyclic voltammetry, the electrochemical oxidation process of axitinib showed diffusion-controlled using the boron-doped diamond electrode; while it exhibited adsorption-controlled using the glassy carbon electrode. The mechanism of the oxidation process was evaluated with model compounds. The calibration curves were linearly obtained in the concentration ranges of 8\u202f×\u202f10−8-2\u202f×\u202f10−6 M and 6\u202f×\u202f10−7-8\u202f×\u202f10−5 M for adsorptive stripping differential pulse voltammetry using the glassy carbon electrode and differential pulse voltammetry using the boron-doped diamond electrode, respectively. The proposed sensors were utilized for the quantification of axitinib in pharmaceutical dosage forms and biological samples with excellent recovery and precision results. The limit of quantifications was calculated as 2.84\u202f×\u202f10−9 and 3.67\u202f×\u202f10−8 M in serum samples in pH 2.0 Britton Robinson buffer on glassy carbon and boron-doped diamond electrodes, respectively. The proposed methods were also evaluated in the presence of some potentials interference compounds and ions.