Study On The HPLC Detection Technology Of Forbidden Colorants In Cosmetics

Pigment Red 53, Acid Violet 49, Solvent Red 49, Basic Violet 1, Pigment Orange 5, Sudan Blue 2 and Sudan IV have certain toxical effect on human health. They get more and more attention in the cosmetics safety issue product by consumers. In this paper, an accurate analysis method for 7 kinds of forbidden colorants in cosmetics, namely, Pigment Red 53, Acid Violet 49, Solvent Red 49, Basic Violet 1, Pigment Orange 5, Sudan Blue 2 and Sudan IV was investigated systematically in order to improve the traditional techniques. This method was achieved easily and suitable for skeleton laboratory.The research consists of two parts.Part one, a method to detect the 7 forbidden colorants in cosmetics by high performance liquid chromatography was established. The samples were extracted with acetonitrile, isolated by a Luna Q18 liquid chromatographic column (150 mm×2 mm,5μm) with a mobile phase include acetonitrile-CH3COONH4 and detected at wavelength of 530 nm by Ultraviolet-Vis detector. The research results indicated that the lowest limit of detection (LOD) are 3-40 μg·g-1 for 7 forbidden colorants, and the average recoveries ranged from 86.67%-98.67%, the relative standard deviation (RSD) were 4.11%-7.25% respectively.Part two, a method to detect the 7 forbidden colorants in cosmetics simultaneously by liquid chromatography-mass spectrometry was established. The samples were extracted with acetonitrile, isolated by a Luna C18 (150 mm×2.1 mm i.d,5μm) with a mobile phase include methanol-water. The sample was separated by liquid chromatography and detected with the multiple reaction monitoring mode by mass spectometry. The research results indicated that the lowest limit of detection (LOD) are 0.03～0.4μg.g-1 for 7 forbidden colorants and the average recoveries from 86.67%～98.22%, the relative standard deviation(RSD) was 4.01%～7.01%.The above-mentioned method is simple, rapid, high sensitivity, good reproducibility. The detection limit, recovery, precision and other technical indexs meet the domestic requirements for 7 forbidden colorants in cosmetics testing, monitoring and confirmation.