Determination of Musk Xylene in Cosmetics by Solid Phase Extraction-Isotope Dilution-Gas Chromatography Tandem Mass Spectrometry
A comprehensive analytical method based on solid phase extraction-isotope dilution-gas chromatography tandem mass spectrometry has been developed for the determination of musk xylene in cosmetics.Various cosmetic samples,including cream,lotion,powder,shampoo and lipstick,were extracted under ultrasonication.The extract was centrifuged,and the upper solution was concentrated by rotary evaporator.The reconstructed solution was then cleaned up by Sep-Pak Silica solid phase extraction cartridge.Qualitative and quantitative analysis was carried out under the MRM mode after the chromatographic separation on DB-5 MS(30 m×0.25 mm,0.25 μm) capillary column.The limit of quantitation(LOQ) for musk xylene was 5 μg/kg.The mean recoveries at the three spiked levels of 5-50 μg/kg were 81.1%-86.9%,with the intra-day precision less than 10% and the inter-day precision less than 12%.The method is accurate,rapid,sensitive and adapt to the inspection of musk xylene in cosmetics.