Evaluation of diuretics in pharmaceuticals by high-performance liquid chromatography with a 0.05 mol dm–3 sodium dodecyl sulfate–3% propanol mobile phase

The use of micellar liquid chromatography for the determination of diuretics in pharmaceutical preparations is studied. Micellar mobile phases containing sodium dodecyl sulfate (SDS), with and without different alcohols, are considered in order to determine the most appropriate combination. The elution behaviour of each diuretic in an unmodified micellar mobile phase is related to the solute–micelle association constants and the stationary phase-water partition coefficients. Diuretics of high, intermediate and low efficacy, contained in several pharmaceutical preparations, are determined using a 0.05 mol dm–3 SDS–3% propanol micellar mobile phase and a C18 column.