气相色谱-三重四极杆串联质谱法检测环境空气中的多环芳烃

建立了气相色谱-三重四极杆串联质谱检测环境空气中多环芳烃的方法，并利用同位素稀释法对多环芳烃进行了测定。将该方法应用于华南地区某大型石化企业周边环境空气中多环芳烃的检测，并与气相色谱-质谱方法进行了对比。结果表明，该方法的仪器检出限（0.01~0.15 μg/L）和定量限（0.03~1.5 μg/L）均优于气相色谱-质谱法（0.1~0.8 μg/L和0.3~3.5 μg/L），并有更好的灵敏度与选择性。当利用气相色谱-质谱作为检测手段时，回收率指示物氘代菲和进样内标六甲基苯均受到了杂质的严重干扰，影响了定量结果的准确性，而三重四极杆串联质谱很好地解决了这些问题。实际样品分析时，标准曲线中16种多环芳烃相对响应因子的相对标准偏差为2.60%~15.6%，氘代化合物的回收率为55.2%~82.3%，空白加标样品的回收率为98.9%~111%，平行样品的相对标准偏差为6.50%~18.4%，采样空白含量范围为未检出~44.3 pg/m³，实验室空白含量范围为未检出~36.5 pg/m³。上述研究表明，分析环境空气中的多环芳烃时，气相色谱-三重四极杆串联质谱方法值得推广。

Analysis of polycyclic aromatic hydrocarbons in air samples by gas chromatography-triple quadrupole mass spectrometry

A method of gas chromatography coupled to triple quadrupole tandem mass spectrometry (GC-MS/MS) has been optimized for the determination of polycyclic aromatic hydrocarbons (PAHs) in air samples. In the analysis step, isotope dilution was introduced to the quantification of PAHs. The GC-MS/MS method was applied to the analysis of the real air samples around a big petrochemical power plant in South China. The results were compared with those obtained by gas chromatography coupled to mass spectrometry (GC-MS). The results showed that better selectivity and sensitivity were obtained by GC-MS/MS. It was found that the external standard of deuterated-PAHs and internal standard of hexamethyl benzene were disturbed seriously with GC-MS, and the problems were both solved effectively by GC-MS/MS. Therefore more accurate quantification results of PAHs were obtained with GC-MS/MS. For the analysis of real samples, the RSDs of relative response factors ranged from 2.60% to 15.6% in standard curves; the recoveries of deuterated-PAHs ranged from 55.2% to 82.3%; the recoveries of spiked samples ranged from 98.9% to 111%; the RSDs of parallel specimens ranged from 6.50% to 18.4%; the concentrations of field blank samples ranged from not detected to 44.3 pg/m³; and the concentrations of library blank samples ranged from not detected to 36.5 pg/m³. The study indicated that the application of GC-MS/MS on the analysis of PAHs in air samples was recommended.