New Insights on Naproxen Quantification Using Voltammetry and Graphite Electrodes: Development of an Optimized and Competitive Methodology

The present work describes a novel, simple and fast electroanalytical methodology for naproxen determination in pharmaceutical formulations. Naproxen's indirect quantification through an adsorption anodic wave was performed at a graphite bar electrode using differential pulse voltammetry. An anodic current maximum was recorded at a potential of -0.3 V referred to a saturated Ag/AgCl electrode, in the presence of 0.1 mol L-1 phosphates buffer at pH 7 as supporting electrolyte. The naproxen's oxidation is an irreversible diffusion-controlled process. A calibration plot was done from which a correlation coefficient of 0.990 was obtained with a sensibility of 4.19 ± 0.62 µA L µg-1, detection and quantification limits of 2.99 and 9.97 µg L-1 respectively.