预浓缩-GC-MS/FID测定环境空气中116种挥发性有机物

Determination of 116 Volatile Organic Compounds in Ambient Air by Preconcentration-GC-MS/FID

采用预浓缩-气相色谱-质谱/氢火焰离子化检测器联用法(预浓缩-GC-MS/FID)结合Dean Switch中心切割和冷柱箱技术,建立了测定环境空气中116种挥发性有机物(VOCs)的分析方法。通过分析色谱程序升温、预浓缩系统一级冷阱、二级冷阱等条件对测定结果的影响,确定了最优参数,评估了此条件下的方法稳定性和准确性。结果显示,程序升温为-20℃~240℃、一级冷阱解析温度为5℃及二级冷阱捕集温度为-50℃时测定效果最佳,116种VOCs在0.50~20.0 nmol·mol^(-1)范围内线性良好,相关系数(R^(2))为0.994~0.9999;在5.00 nmol·mol^(-1)加标浓度水平下重复进样6次,加标回收率为91.2%~117%,相对标准偏差(RSD)为2.3%~12%。方法简便快速、稳定性好、准确度高,可用于环境空气中116种VOCs的定性定量分析。

An analytical method for the determination of 116 volatile organic compounds(VOCs)in ambient air was developed by using pre concentration-gas chromatoc-mass spectrometry/hydrogen flame ionization detector(pre concentration-GC-MS/FID)combined with Dean Switch center cutting and cold column box technique.By analyzing the influence of temperature rise in chromatographic program,primary cold trap and secondary cold trap in preconcentration system on the determination results,the optimal parameters were determined,and the stability and accuracy of the method were evaluated under these conditions.The results showed that the best results were obtained when the program temperature was -20℃~240℃,the analytic temperature of the primary cold trap was 5℃ and the trapping temperature of the secondary cold trap was -50℃.The 116 VOCs showed good linearity in the range of 0.50~20.0 nmol·moL^(-1),with a correlation coefficient(R2)of 0.994~0.9999;Repeat the injection 6 times at a concentration level of 5.00 nmol·moL^(-1),with a recovery rate of 91.2%~117% and a relative standard deviation(RSD)of 2.3%~12%.The method is simple,rapid,stable and accurate,and can be used for qualitative and quantitative analysis of 116 VOCs in ambient air.