| An HPLC method was developed for the determination of acid yellow 36,pigment red 53∶1,pigment orange 5,sudan Ⅱ and sudan Ⅳ in cosmetics.The extraction conditions of five prohibited coloring agents in cosmetic samples,including wax,powder and liquid,were investigated.Using tetrabutylammonium hydroxide as an ion-pair reagent,the optimum chromatographic conditions of the prohibited coloring agents were investigated.The optimal conditions were as the follows:stationary phase：Hypersil C18（4.6 mm×250 mm,5 μm）,mobile phase：acetonitrile(A）-0.01 mol/L tetrabutylammonium hydroxide and 0.01 mol/L citric acid(pH 8.2,B）,flow rate：1.0 mL/min,column temperature：30 ℃ and detection wavelengths：416,484,514 nm.The calibration curves of five prohibited coloring agents showed good linearities in the range of 0.2-50 mg/L with correlation coefficients more than 0.999 and LODs（S/N=3） of 0.2-0.5 mg/L.The five prohibited coloring agents were verified by HPLC-MS/MS.At three spiked levels,the average recoveries were between 85% and 102%,with relative standard deviations of 0.5%-3.6%.The method was accurate,simple and rapid,and could be used to determine acid yellow 36,pigment red 53∶1,pigment orange 5,sudan Ⅱ and sudan Ⅳ in cosmetics. |