Determination of 5 Prohibited Components in Cosmetics by Ultra-High Pressure Liquid Chromatography-Triple Quadrupole Tandem Mass Spectrometry Combined with QuEChERS

The method mentioned by the title was proposed for simultaneous determination of 5 prohibited components including cyclophosphamide, azacyclonol, aminopentamide, narcotine and metyrapene in different cosmetic matrices. The samples of water emulsion and essential oil cosmetics were extracted with methanol, and the samples of cream cosmetics were dispersed with saturated sodium chloride solution and extracted with anhydrous ethanol. Then both were purified with octadecyl silane boned silica gel (C₁₈). The targets were separated on Waters BEH C₁₈ column using a mixed solution of 0.1% (volume fraction) formic acid solution and acetonitrile at different volume ratios as the mobile phase for gradient elution. Multiple reaction monitoring (MRM) mode in mass spectrometry analysis was carried out under positive ion mode of electrospray ion source, and matrix matching method was used for quantitative analysis. As shown by the results, linear relationships between the corresponding peak areas and mass concentrations of 5 prohibited components were found in the range of 5-200 μg·L⁻¹, with detection limits (3S/N) in the range of 5-100 μg·kg⁻¹. Test for recovery at 3 concentration levels was conducted in different blank matrices, and the recoveries of 5 prohibited components ranged from 90.1% to 115%, with RSDs (n=6) of the determined values in the range of 2.0%-14%.