Determination of three constituents in compound ketoconazole ointment by RP-HPLC

Objective  To establish a RP-HPLC method for determination of ketoconazole, mupirocin and mometasone furoate in compound ketoconazole ointment. Methods  RP-HPLC was conducted on a Intersil ODS-3 column (250 mm×4.6 mm, 5 μm), with methanol-PBS with pH 5.5 (65:35) as the mobile phase and the column temperature was 45 ℃. The flow rate was 1.0 ml/min, and the detection wavelength was 248 nm. Results  The methodological verification showed that ketoconazole, mupirocin and mometasone furoate had a good linearity (r≥0.9995). The inter/intra-day precisions were less than 3.0%, The recovery rates were between 90% and 108%. The stability and repeatability of RSD were also less than 3.0%, which met the requirements of method validation. The contents of the three components in three batches were determined by the new method. Conclusion  The method is simple and reliable. It can provide a basis for the quality control of compound ketoconazole ointment and lay a foundation for its quality standard research.