Determination of methylparaben, propylparaben and chlorpromazine in chlorpromazine hydrochloride oral solution by high-performance liquid chromatography

A reversed-phase high-performance liquid chromatographic assay method was developed and validated for the simultaneous determination of methylparaben and propylparaben preservatives and chlorpromazine hydrochloride active component in a liquid oral pharmaceutical formulation. The method separated the analytes as well as some degradants and other components, providing good resolution and moderate tailing. The performance of various C-18 columns was compared. There were significant differences in selectivity and only a few phases showed acceptable tailing without the addition of triethylamine modifier in the mobile phase. (C) 1998 Elsevier Science B.V.