顶空-气质联用法测定卷烟包装材料中苯不确定度评定

Evaluation of Uncertainty of Volatile Benzene in Cigarette Packing Material by HS-GC/MS

采用顶空-气相色谱/质谱联用法分析卷烟包装材料中苯的残留不确定度,通过建立数学模型,分析不确定度的主要来源,计算各个不确定度分量,将不确定度合成,得到该分析方法的测量不确定度评定方法。结果表明,样品测定过程中总的重复性引起的测量不确定度所占权重最大,其次是拟合标准工作曲线所引入的不确定度,配制标液过程中引入的测量不确定度所占权重最小。通过统计分析发现,回收率与100%差异不显著,当苯残留含量为0.010 mg.m-2时,该分析方法的测量扩展不确定度为0.001 mg.m-2(k=2)。

An analytical method to determine volatile benzene in cigarette packing was presented by headspace gas chromatography mass spectrometry （HS-GC/MS）, and the method for the uncertainty measurement was evaluated. The mathematical model of measurement was set up. The different parts of uncertainty were analyzed. The combined standard uncertainty was calculated, and the evaluation of the uncertainty of this analytical method was observed. The results indicate that the uncertainty of the repeatability is the largest factor contributed to the combined uncertainty. The next is caused by the benzene content calculation using the standard curves, and the uncertainty of preparing the standard solution is low. In addition, the recovery values of this method with 100% is not significant by statistic analysis. When the content of benzene residue is 0. 010 mg· m^-2 , the expanded uncertainty is 0. 001 mg·m^-2 （k=2）.