Simultaneous Determination of Magnesium Ascorbyl Phosphate, Ascorbyl Glucoside, Kojic Acid, Arbutin and Hydroquinone in Skin Whitening Cosmetics by HPLC

 

SHOU-CHIEH HUANG¹, CHENG-CHIN LIN¹, MING-CHUAN HUANG^1* AND KUO-CHING WEN²

^1. Bureau of Food and Drug Analysis, Department of Health, Executive Yuan, 161-2 Kunyang St., Nangang District, Taipei City 115, Taiwan (R.O.C.)
^2. Department of Cosmeceutics, China Medical University, 91 Hsueh-Shih Rd., North Section, Taichung City 404, Taiwan (R.O.C.)

(Received: November 13, 2002; Accepted: September 29, 2003)

ABSTRACT

   A high performance liquid chromatographic method was developed for simultaneous determination of 5 whitening ingredients: magnesium ascorbyl phosphate, ascorbyl glucoside, kojic acid, arbutin and hydroquinone decomposed from arbutin in cosmetics. Samples were extracted with 0.05 M KH₂PO₄ buffer solution (pH 2.5) and analyzed using a Cosmosil 5 C18-AR-II column. A mixture of 0.05 M KH₂PO₄ buffer solution (pH 2.5) and methanol (99:1, v/v) was used as mobile phase. The UV detector was set at 280 nm. Pyridoxine was used as an internal standard. The related coefficients, R², of regression equations of the 5 standard curves were 0.9998-1.0000. The relative standard deviations of the 5 ingredients for intraday and interday analysis were less than 2.4%. The average recoveries of these 5 ingredients spiked in sample ranged from 93.5% to 103.3%. The relative standard deviations of average recoveries were less than 1.3%. The limits of quantitation in cosmetics were 80.0, 20.0, 3.0, 15.0 and 10.0 mg/mL for magnesium ascorbyl phosphate, ascorbyl glucoside, kojic acid, arbutin and hydroquinone, respectively.

Key words: magnesium ascorbyl phosphate, ascorbyl glucoside, kojic acid, arbutin, hydroquinone, whitening cosmetics, HPLC