Determination of methylparaben, propylparaben, triamcinolone acetonide and its degradation product in a topical cream by RP-HPLC.

A novel reversed-phase high-performance liquid chromatographic (RP-HPLC) method was developed and validated for the determination of active component triamcinolone acetonide, its degradation product triamcinolone (occurring in formulation after long-term stability tests) and two preservatives presented in the cream-methylparaben and propylparaben, using hydrocortisone as an internal standard. The chromatographic separation was performed on a Supelco Discovery C18 column; the mobile phase for separation of all compounds consists of a mixture of acetonitrile and water (40:60 v/v). The analysis time was less than 9 min, at a flow rate of 0.6 mL min(-1) and detection at 240 nm. The method was found to be applicable for routine analysis (stability tests, homogeneity) in the pharmaceutical product topical cream Triamcinolon cream 0.1%.