DEVELOPMENT AND VALIDATION OF AN RP-HPLC METHOD FOR SIMULTANEOUS ESTIMATION OF METHYLPARABEN AND PROPYLPARABEN IN HERBAL CREAM FORMULATION

Preservatives play a crucial role in maintaining the microbiological stability and safety of cosmetic and herbal formulations. Methylparaben (MP) and propylparaben (PP) are widely used preservatives; however, their accurate and simultaneous determination in complex herbal matrices remains analytically challenging. The present study describes the development and validation of a simple, rapid, and reliable reverse-phase high-performance liquid chromatography (RP-HPLC) method for the simultaneous estimation of methylparaben and propylparaben in an herbal cream formulation. Chromatographic separation was achieved on a C18 column (250 × 4.6 mm, 5 μm) using a mobile phase consisting of potassium dihydrogen phosphate buffer, methanol, and triethylamine in the ratio of 347:650:3 (v/v/v), at a flow rate of 1.0 ml/min with UV detection at 272 nm. The retention times for methylparaben and propylparaben were found to be approximately 3.95 and 6.28 minutes, respectively, with good resolution and peak symmetry. The developed method was validated in accordance with ICH Q2(R1) guidelines for system suitability, specificity, linearity, accuracy, precision, range, and robustness. The method showed excellent linearity with correlation coefficients greater than 0.999 for both analytes. Accuracy studies demonstrated recoveries in the range of 98–102%, while precision studies yielded %RSD values below 2%. The method was found to be robust against small deliberate variations in chromatographic conditions. The validated RP-HPLC method is suitable for routine quality control analysis of methylparaben and propylparaben in herbal cream formulations.