Determinação de Naproxeno em fármacos utilizando o sistema de análise por injeção em batelada (BIA) em eletrodo de carbono vítreo modificado com alumina

Abstract

Quality control of medicines is paramount importance to ensure their effectiveness and reduce the occurrence of undesirable effects caused by the presence of more or less active ingredients, impurities and/or degradation products. For this, analytical techniques have been recommended in pharmacopoeias, involving classical and instrumental methods, mainly for the quantification of active ingredients in pharmaceutical formulations. Quantitative analyzes were performed to comparatively evaluate the performance of the clean and modified alumina glass carbono eletectrode (GCE) as an electrochemical sensor for detection of naproxen (NPX) in pharmaceutical formulations using the batch injection analysis system (BIA) and the results obtained were compared with commonly used methods, high performance liquid chromatography (HPLC) and UV-Vis spectrophotometry. NPX is an important non-steroidal anti-inflammatory drug widely used in general pain relief, which justifies the importance of its analysis. The proposed method was applied to three samples of popularly consumed drugs. Preliminary studies showed that it is not possible to determine NPX in bare GCE due to the large adsorption on its surface. Therefore, this work presents modification of GCE with alumina for the determination of NPX besides the application of a cleaning potential and agitation system. to obtain reproducible and stable responses (RPD = 5.2% for n = 10), with low limit of detection and quantification (LD = 0.32 mol L-1 | LQ = 1.08 mol L-1), high analytical frequency of 120 injections/hour.