摘要
为研究在卷烟烟气总粒相物和人体pH条件下，游离态、两种单质子化形式和二质子化形式尼古丁的相对百分含量，在气相和水相B3LYP／6．311＋＋G（却）水平，分别对3种形式尼古丁的稳定构象进行了优化，计算了气相和水相玻尔兹曼分布百分比、气相质子结合能、玻尔兹曼加权溶剂化能等物理化学参数，并根据尼古丁的pKa常数计算了中式卷烟烟气总粒相物中游离态形式在总尼古丁中的含量。计算结果显示：（1）在气相中，两种单质子化形式尼古丁共存，两者可以相互转化，处于动态平衡中；（2）在气相中尼古丁的单质子化主要发生在吡啶环N原子上，在水相中尼古丁的单质子化主要发生在四氢吡咯环N原子上；（3）在中式卷烟烟气总粒相物中游离态形式在总尼古丁中的含量约为0．3％-1．9％。
The conformational percentage of nicotine in free, mono-protonated and dipronated forms in cigarette smoke were investigated under pH value of human body. Stable conformations of nicotine were optimized separately at B3LYP/6-311＋＋G （d,p） level in gas phase and water phase. Boltzrnann populations in gas phase and water phase, proton affinity, Boltzmann weighted solvation energy and other chemical parameters were also calculated. Ratio of free-state nicotine to total nicotine in Chinese-style cigarette smoke was calculated according to pKa constant of nicotine and pH value. Results showed that： （1） in gas phase, two forms of mono-protonated nicotine coexisted in dynamic balance; （2） in gas phase, mono-protonation of nicotine mainly occurred on the pyridine nitrogen, while on pyrrolidine nitrogen in water phase; （3） ratio of free-state nicotine to total nicotine in Chinese-style cigarette smoke ranged from 0.3% to 1.9%.
出处
《中国烟草学报》
EI
CAS
CSCD
北大核心
2016年第3期1-9,共9页
Acta Tabacaria Sinica
基金
云南省科技厅项目"引导类工业[2014]01号"
中国烟草总公司科技项目"110201402040"
关键词
尼古丁
单质子化尼古丁
玻尔兹曼分布
密度泛函理论计算
nicotine
mono-pronated nicotine
boltzmann population
density functional theory calculation
