异丙醇-(NH4)_2SO_4-H_2O双水相体系样品前处理结合GC/MS测定化妆品中苯系物

Determination of benzene series in cosmetics samples through isopropanol-(NH_4)_2SO_4-H_2O aqueous two-phase method for samples pretreatment combined with gas chromatography/mass spectrometry

本文用异丙醇-（NH4）2SO4-H2O双水相体系高效提取化妆品中的苯系物（BTEX,苯、甲苯、乙苯、对二甲苯、间二甲苯和邻二甲苯）,结合气相色谱-质谱联用（GC-MS）实现了对化妆品中六种BTEX的快速准确测定。实验主要考察了双水相体系的形成条件,并探讨了双水相体系对BTEX的萃取效率。实验结果表明：异丙醇不仅具有较好的破乳性能,而且对样品中BTEX有较高的提取效率;硫酸铵具有较好的盐析分相作用;化妆品中BTEX的萃取率与异丙醇水溶液的体积分数有关,当双水相体系中水与异丙醇的体积之比约为3∶2时,异丙醇与化妆品中的BTEX可接触充分,萃取率较高。该方法对化妆品中BTEX的测定回收率为81.1-98.2%,检出限为1.1-3.9 ng·g。

Based on isopropanol-（ NH4 ） 2SO4-H2O aqueous two-phase system, the benzene series in cosmetics samples were quick determined by gas chromatography/mass spectrometry. The influence factors on formation of solvent-salt-H2O system were discussed in depth. And the influence of the aqueous two phase system on extraction of benzene series in cosmetics samples was investigated detailedly. The results showed that isopropanol has superbly abilities to damage the emulsion of samples and to extract BTEX from samples efficiently. Ammonium sulfate got high efficiency for salting out phase separation. In the procedures of cosmetics samples pretreatment, the BTEX extraction rate is related to the volume fraction of isopropyl alcohol. When the volume ratio of water and iso-propyl alcohol in aqueous two-phase system is approximately 3 -2,the isopropyl alcohol and BTEX in cosmetics can be fully contact, and the extraction rate is higher. The spiked recoveries by this proposed method were 81. 1 - 98. 2 % , and the detection limits were in the range of 1. 1 -3. 9 ng·g.