气相色谱-质谱法测定大气颗粒物中多环芳烃化合物的方法改进

Method improvement for determining polycyclic aromatic hydrocarbon compounds in atmospheric particulates by gas chromatography-mass spectrometry

目的为更准确了解空气滤膜中16种多环芳烃的含量,对气相色谱质谱检测方法进行了改进。方法本文采用两根不同的色谱柱分别对16种多环芳烃进行分离,用质谱进行检测,超声波提取样品滤膜上的多环芳烃,进样量提高到4μl,并且优化了程序升温的条件。结果 16种多环芳烃分离效果DB-EUPAH色谱柱更优于HP-5MS色谱柱,尤其DB-EUPAH色谱柱能够把样品中苯并(b)荧蒽、苯并(k)荧蒽、苯并(j)荧蒽3种同分异构体完全分开,提高了苯并(b)荧蒽、苯并(k)荧蒽定量的准确度;16种多环芳烃在0.5μg/L^20μg/L和20μg/L^500μg/L的浓度内,线性关系均良好,相关系数在0.997~0.999 9,加标回收率在86%~113%,进样6次的相对标准偏差为1.86%~5.69%。结论改进后的方法能获得满意的分离效果,定量更准确,方法的准确度和精密度均较好。

Objective To more accurately understand the contents of 16 polycyclic aromatic hydrocarbons(PAHs) in air filter membranes,gas chromatography mass spectrometry(GC-MS) detection method was improved.Methods 16 PAHs were separated by two different chromatographic column and determined by mass spectrometry(MS).PAHs in filter membranes are extracted by ultrasonic,the injection quantity was increased to 4 μL,and the temperature-programmed condition was optimized.Results The separation efficiency of DB-EUPAH chromatographic column to 16 PAHs was better than HP-5 MS chromatographic column.Especially,Benzo(b) fluoranthene(BbF),Benzo(k)fluoranthene(BkF) and Benzo(j) fluoranthene(BjF) Isomers in sample were enough to separate.The accuracy of quantitative determination of Benzo(b) fluoranthene(BbF),Benzo(k) fluoranthene(BkF) was enhanced;the correlation coefficients of 16 PAHs in PM 2.5 were within 0.997-0.999 9 in the range of 0.5 μg/L-20 μg/L and 20 μg/L-500 μg/L.The recoveries of 16 PAHs were within 86%-113%.The RSD of injecting six times was within 1.86%-5.69%.Conclusion The improved method can obtain satisfactory separation effect,the quantification is more accurate,and the accuracy and precision of the method are better.