中文摘要：

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-ESIMS/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100μL氘代混合内标后用10mL100mmol/L醋酸铵水溶液萃取,萃取液过水相滤膜后直接进行LC-ESIMS/MS检测。选用AgilentZorbaxEclipseXDB-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0.007μg/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。

英文摘要：

N-nitrosonornicotine （ NNN） ,4-（ methylnitrosamino）-1-（ 3-pyridyl）-1-butanone （ NNK） ,N-nitro-soanatabine （ 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 mo-nitoring （ 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.