HPLC analysis for the contamination of hydroquinone in skin-whitening herbal cosmetic cream.

Abstract

The purpose of this study was to investigate the contamination of hydroquinone in skin-whitening herbal cosmetic cream sold commercially in the area of Khon Kaen city. A high performance liquid chromatographic method equipped with diode array detector was used for the analysis of hydroquinone in these products. Sample preparation was performed by using methanol for extracting hydroquinone from herbal cosmetic cream. The analysis was carried out using Hypersil^®ODS C18 column and a mixture of methanol:water in the ratio of 40:60 was used as the mobile phase. The UV detector was Set at 289 nm for the detection of hydroquinone.The coefficient of determination (R² ) for the regression equation of the standard curve was 0.9999. The relative standard deviations for within-day and between-day were less than 2%. The limit of detection and limit of quantitation were 0.01 and 0.1 µg/ml, respectively. From the analysis of twenty-three samples, hydroquinone was detected in four samples. The amounts of hydroquinone were in the range of 2.06-3.29 %w/w. Thus, there should be concern about the contamination of hydroquinone, which will lead to the quality control improvement of these products in the future.