Determinação de besilato de amlodipina e atenolol utilizando eletrodo de diamante dopado com boro e análise por injeção em batelada com detecção amperométrica

Abstract

There are no reports in the literature of electroanalytical methods for analysis of pharmaceutical formulations containing amlodipine besylate (AML) and atenolol (ATN). In this context, this study aimed to use the boron-doped diamond (BDD) electrode and the batch injection analysis (BIA) system for sequential determination of these compounds in pharmaceutical formulations. The sequential determination of the two compounds was performed by applying two potentials as a function of time using BR buffer pH 2.0 as supporting electrolyte. AML was selectively detected at +1.00 V and ATN at +1.65 V. An additional potential pulse (0.0 V / 300 ms; pulsed amperometric detection) was applied to avoid contamination/passivation of the BDD electrode surface. Under these conditions both compounds showed a linear response range of 5 to 25 μmol L-1 (r> 0.99), good repeatability (RSD < 3.2 %; n = 10), limits of detection 0.074 μmol L-1, limits of quantification 0.25 μmol L-1 and high analytical frequency (> 70 injections h-1). The results obtained with the proposed method were compared to those obtained by HPLC and similar results were obtained (at 95% of confidence level).