Analysis of salicylic acid, arbutin and corticosteroids in skin whitening creams available in Pakistan using chromatographic techniques

Abstract

Background: A simple, new and efficient reversed-phase high-performance liquid chromatography method was developed and validated for the separation of most popular ingredients in skin whitening creams.

Methods: For RP-HPLC analysis, a Hibar(®) C18 250 mm × 4.6 mm, 5 μm column (Merck Millipore, Carolina, USA) as stationary phase with a mobile phase consisting a mixture of acetonitrile, methanol and water 40 : 40 : 20 (pH 7.0), respectively, at flow rate of 0.8 mL min(-1) (total run time 10 min) at room temperature was used. Detection was performed at 254 and 280 nm using photodiode array detector. The method was validated in accordance with ICH guidelines with respect to linearity, accuracy, precision, specificity, limit of detection and quantification.

Results: The method results in excellent separation of skin whitening agents in cosmetic creams. The method is specific for salicylic acid, arbutin, cortisone, hydrocortisone, betamethasone valerate and betamethasone dipropionate. The calibration curve of skin whitening agents was linear with the regression analysis showed r(2) ≥ 0.999. %RSD for inter- and intraday precision were determined as 0.461 and 0.329 for salicylic acid, 0.427 and 0.317 for arbutin, 0.360 and 0.346 for cortisone, 0.336 and 0.350 for hydrocortisone, 0.463 and 0.339 for betamethasone valerate and 0.385 and 0.372 for betamethasone dipropionate, respectively. LOD and LOQ were calculated as 0.48 and 1.20 μg mL(-1) for salicylic acid, 0.09 and 0.22 μg mL(-1) for arbutin, 0.07 and 0.18 μg mL(-1) for cortisone, 0.06 and 0.24 μg mL(-1) for hydrocortisone, 0.07 and 0.20 μg mL(-1) for betamethasone valerate and 0.02 and 0.06 μg mL(-1) for betamethasone dipropionate. The recovery of skin whitening agents were 97.18% for salicylic acid, 97.99% for arbutin, 98.30% cortisone, 97.63% for hydrocortisone, 98.65% for betamethasone valerate and 98.18% for betamethasone dipropionate, respectively. According to this study, salicylic acid is present in 87.88% skin whitening creams, arbutin in 96.97%, cortisone in 60.60%, hydrocortisone in 48.48%, betamethasone valerate in 15.15% and betamethasone dipropionate present in 12.12% cosmetic creams available in Pakistan.

Keywords: HPLC-PDA; corticosteroids; skin whitening creams.