液相色谱-串联质谱法测定卷烟主流烟气中的四种致癌物

N-亚硝基降烟碱（NNN）、4-（亚硝基甲氨基）-1-（3-吡啶基）-1-丁酮（NNK）、N-亚硝基新烟草碱 （NAT）和N-亚硝基假木贼碱（NAB）是4种广泛存在于烟草和烟气中的致癌物,准确测定其含量对评估其对人体健康的影响有着重要的作用。采用液相色谱-电喷雾串联质谱(LC-ESI MS/MS)技术建立了卷烟主流烟气中NNN、NNK、NAT和NAB的测定方法,并将其用于中国烤烟和混合型卷烟主流烟气的分析。卷烟主流烟气通过剑桥滤片捕集,捕集烟气后的滤片在加入100 μL氘代混合内标后用10 mL 100 mmol/L醋酸铵水溶液萃取,萃取液过水相滤膜后直接进行LC-ESI MS/MS检测。选用Agilent Zorbax Eclipse XDB-C18色谱柱,以流动相0.1%(v/v)乙酸水溶液和0.1%（v/v）乙酸甲醇溶液梯度洗脱,质谱检测采用正离子扫描,多反应监测模式。NNN、NNK、NAT和NAB的检出限分别为0.019、0.002、0.008和0.007 μg/L,回收率为84.9%～104.5%,相对标准偏差(n=8)为2.96%～6.65%。该方法的检出限低,特异性好,适用于卷烟主流烟气中NNN、NNK、NAT和NAB释放量的检测。

Determination of four carcinogens in mainstream cigarette smoke by liquid chromatography-tandem mass spectrometry

N-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N-nitrosoanatabine (NAT) and N-nitrosoanabasine (NAB) are the most abundant carcinogens identified in tobacco and tobacco smoke. The accurate quantifications of NNN, NNK, NAT and NAB are necessary to evaluate its impact on the public health. A liquid chromatography-electrospray tandem mass spectrometry (LC-ESI MS/MS) method was developed to simultaneously determine NNN, NNK, NAT and NAB in mainstream cigarette smoke. Mainstream smoke was collected in a Cambridge filter pad and then was extracted by 10 mL 100 mmol/L ammonium acetate after 100 μL of mixed deuterated internal standards was added. Then the extract was detected by using positive electrospray ionization on a tandem mass spectrometer in multiple reaction monitoring (MRM) mode. NNN, NNK, NAT and NAB were separated on a Zorbax Eclipse XDB-C18 column with the gradient elution using mobile phase A (0.1% acetic acid in water) and mobile phase B (0.1% acetic acid in methanol). The detection limits for NNN, NNK, NAT and NAB were 0.019, 0.002, 0.008 and 0.007 μg/L, respectively. The recoveries were varied from 84.9% to 104.5% for Chinese Virginia cigarettes and the relative standard deviations (n=8) ranged from 2.96% to 6.65%. This proposed approach, which provides a higher sensitivity and specificity, is suitable for the determination of NNN, NNK, NAT and NAB in mainstream cigarette smoke.