同位素稀释-顶空气相色谱-质谱联用法测定化妆品中的二噁烷残留量

建立了化妆品中二噁烷的同位素稀释-顶空气相色谱-质谱联用测定方法。称取2 g化妆品样品于顶空样品瓶中,加入1 g氯化钠及20 mg/L氘代二噁烷内标溶液1 mL,再加入9 mL水。密封后摇匀,置于顶空进样器中,在70℃平衡40 min。气液平衡后的上部气体经HP-5 MS石英毛细管气相色谱柱(30 m×0.25 mm×0.25μm)分离后,采用选择离子扫描模式进行质谱定性及定量分析。二噁烷的方法定量限为2.5 mg/kg;在2.5~50 mg/kg的3个添加水平范围内的平均回收率为90.5%~104.0%,相对标准偏差为1.26%~3.98%。本方法准确、简便、快速,能够满足化妆品样品中二噁烷残留量的检测要求。

Determination of dioxane residue in cosmetics by isotope dilution-headspace gas chromatography-mass spectrometry

A comprehensive analytical method based on isotope dilution-headspace gas chromatography-mass spectrometry was developed for the determination of dioxane residue in the cosmetics. Cosmetic sample (2 g) was placed in a headspace vial. Then, 1 g sodium chloride, 1 mL d₈-dioxane solution (20 mg/L) and 9 mL water were added. The vial was sealed and heated at 70 ℃ for 40 min. The qualitative and quantitative analyses were carried out for the analyte in selected ion monitoring (SIM) mode after the chromatographic separation on an HP-5MS column (30 m×0.25 mm×0.25 μm). The limit of quantification (LOQ) for dioxane was 2.5 mg/kg. The mean recoveries were 90.5%-104.0% at the spiked levels of 2.5-50 mg/kg with the relative standard deviations in the range of 1.26%-3.98%. The method is accurate, simple, rapid, and applicable for the inspection of dioxane residue in cosmetics.