Determinação de minoxidil em formulações farmacêuticas usando permanganometria

Abstract

A titrimetric procedure for the determination of minoxidil using KMnO4 as oxidizing agent is described. The best conditions were optimized considering the H2SO4, KMnO4 and minoxidil concentrations, the temperature of the system and the order of addition of the reactants. The method was applied to commercial samples and compared with the results from a standard chromatographic procedure. Recoveries from 94.5 to 95.2 % were observed depending on the sample. Comparison with the chromatographic procedure reveled relative errors of -1.00 to – 5.26 %. The method was relatively fast, easy to perform and can be a low cost alternative for pharmaceutical samples in which minoxidil concentration is relatively high.