顶空气相色谱法同时测定食品包装中氯乙烯与偏氯乙烯单体

Simultaneous Determination of Vinyl Chloride and Vinylidene Chloride in Food Packaging by Head-space Gas Chromatography

建立一种用于食品塑料包装中氯乙烯与偏氯乙烯含量的顶空气相色谱检测方法,对顶空平衡温度、平衡时间的影响进行研究,结果表明:平衡温度在80℃、平衡时间在30 min时,选用Stabilwax(30 m×0.25 mm,0.25μm)的毛细管色谱柱上能得到很好的分离;该方法中,氯乙烯单体的检出限为0.5 mg/kg,偏氯乙烯单体的检出限为1.0mg/kg。在0.1 mg/L^2.0 mg/L范围内线性关系良好,相关系数均大于0.999;平均加标回收率分别为90.0%~92.1%和85.0%~91.4%,相对标准偏差分别为2.5%~5.0%和2.3%~5.3%。

A method was established for simultaneous determination of vinyl chloride and vinylidene chloride in food plastic packaging by head-space gas chromatography. The effects of equilibrium temperature and equilibrium time on the determination were studied. The results showed that when choose Stabliwas capillary column （30 m×0.25 mm,0.25μm）, equilibrium temperature at 80 ℃ and equilibrium time at 30 min, the two groups of substances can get good separation; The detection limits of vinyl chloride and vinylidene chloride were 0.5 mg/kg and 1.0 mg/kg. The linear calibration curve was obtained in the range of 0.1 mg/L -2.0 mg/L with a linear correlation coefficient of 0.999. The average recoveries for vinyl chloride and vinylidene chloride were 90.0% ~92.1% and 85.0%~91.4%, with relative standard deviations of 2.5%~5.0% and 2.3%~5.3%.