Determination of Clobetasol Propionate in Cosmetic Products by High Performance Liquid Chromatography

Abstract

       The method for determination of clobetasol propionate in cosmetic products was developed. Sample was extracted from cosmetic product by methyl alcohol. Then, the extracted compound was analyzed by HPLC using Hypersil BDS C18 column (250 mm × 4.6 mm I.D., 5 μm) with a 1.0 ml/min flow rate of a (v/v) gradient elution of acetonitrile; water mobile phase starting from 33:67 for 10 minutes and then using gradient to 50:50 within 10 minutes and maintaining at 50:50 for 15 minutes, a 10 μl sample injection, and PDA detection monitoring at 240 nm. The results of method validation showed that the method was specific to the determination of clobetasol propionate, clobetasol propionate was separated with retention time of 30 minute and was not disturbed by other substances. The method was linear between concentration of standard solution and peak area over the range of 0.8 – 60 μg/ml with correlation coefficient 0.9996 and the correlation between concentration of standard adding to sample and detection concentration over the range 3.2 – 480 mg/kg. with correlation coefficient 0.9995. The limit of detection was 0.8 mg/kg. and limit of quantitation was 3.2 mg/kg. Accuracy was analyzed by the recovery and found in the range of 90 – 94%. The precision was demonstrated by %RSD in acceptable range of 0.8 – 4.7 with the acceptable, intermediate precision was shown by %RSD in acceptable range of 2.2 – 2.6. The relative uncertainty was 7.7%. In 2013, this validated method was used for quantitative analysis of clobetasol propionate in 11 lotion samples. The results showed that clobetasol propionate was detected in every sample in range 8.0 – 449.8 mg/kg. In conclusion, this method was suitable for analysis of clobetasol propionate in cosmetic products for consumer protection.