Optimization of cleaning and analytical method for determination of arbutin, hydroquinone and kojic acid in cosmetic products

Hydroquinone, arbutin and kojic acid are herbal-based skin whitening compounds that are used in many cosmetics. Today, the lack of side effects of arbutin and kojic acid has made them a valuable alternative to hydroquinone. Due to the toxic effects of whitening compounds, it is necessary to control the amount of use of these in the whitening products so that their concentration is within the permissible range.

Therefore, the purpose of this study was to identify and quantify these three compounds in anti-lacquer products. In this research, the best separation of analytes has been tried by changing the HPLC mobile phase.

Different samples were taken from the supply level. After extraction and preparation of samples, the solution was injected into HPLC-UV. In order to optimize the method, three different mobile phases were used to identify the compounds. By comparing the obtained peaks with the standard peaks, the Whitening compounds were identified and quantified.

The results showed that hydroquinone and kojic acid were applied in three products and arbutin in one product and the concentration of all the compounds used were within the standard range. Four out of the eight companies surveyed did not correctly identify the compounds used in their products.

Reverse Phase HPLC-UV is also one of the best methods for determination and quantification the whitening compounds and water composition: acetonitrile with a ratio of 80:20 v/v is the most appropriate mobile phase in this method.