Determination of Chromium(¢ö) and Chromium(¢ó) in Cosmetics by High Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry

KeyWord:high performance liquid chromatography-inductively coupled plasma mass spectrometry(HPLC-ICP-MS)  cosmetics  chromium(¢ö)  chromium(¢ó)

Abstract:

      A method was developed for the simultaneous determination of chromium(¢ö) and chromium(¢ó) by high performance liquid chromatography-inductively coupled plasma mass spectrometry(HPLC-ICP-MS).The sample was extracted with 10 mmol/L EDTA solution(pH 7.0).The chromatographic separation was performed on an Agilent Bio-WAX column(4.6 mm¡Á50 mm,5 ¦Ìm) utilizing 0.075 mol/L nitric acid(pH 7.0) as mobile phase.Identification and quantitation were achieved by ICP-MS.Under the optimal conditions,the linear ranges for Cr(¢ö) and Cr(¢ó) were observed from 0 ¦Ìg/L to 100 ¦Ìg/L with correlation coefficients(r2) of 0.999 9.The limits of detection for Cr(¢ö) and Cr(¢ó) were 6 ¦Ìg/kg and 2 ¦Ìg/kg,and the limits of quantitation were 18 ¦Ìg/kg and 6 ¦Ìg/kg,respectively.Average recoveries for Cr(¢ö) and Cr(¢ó) at three spiked levels ranged from 85.1% to 113% with relative standard deviations of 0.4%-4.6%.Through the analysis of actual samples,Cr(¢ö) and Cr(¢ó) were detected out in cream lotion and powder cosmetics.With good reproducibility and high sensitivity,this method is suitable for the simultaneous determination of Cr(¢ö) and Cr(¢ó) in different types of cosmetics as Cr(¢ö) is stable under neutral conditions.