计算机辅助制备烟碱分子印迹聚合物及其在烟碱纯化中的应用

Computer assisted preparation of nicotine molecularly imprinted polymer and its application in the purification of nicotine

基于密度泛函理论(DFT)对烟碱分子印迹聚合体系进行辅助设计,并优化了烟碱分子印迹聚合物(NMIPs)的制备工艺。以三氟甲基丙烯酸(TFMAA)为功能单体、乙二醇二甲基丙烯酸酯(EGDMA)为交联剂、偶氮二异丁腈(AIBN)为引发剂,烟碱与TFMAA摩尔比为1∶3、乙腈用量为60 mL时,所得NMIPs吸附效果较优,印迹因子为1.8。考察了NMIPs的吸附性能,并借助Scatchard模型分析发现:NMIPs存在高亲和和低亲和两类吸附结合位点,最大表观结合量为28.56 mg/g。利用所制备的NMIPs纯化烟草复烤尾气,使烟碱相对含量由63.58%上升至89.78%;经NMIPs纯化,新鲜烟叶挥发油中的烟碱相对含量由89.39%上升至95.71%。

The nicotine molecular imprinting polymerization system was designed based on the density functional theory(DFT),and the preparation process of nicotine molecular imprinting polymers(NMIPs)was optimized.Under the conditions of 2-(trifluoromethyl)acrylic acid(TFMAA)as functional monomer,ethylene glycol dimethacrylate(ECDMA)as cross-linking agent,azobisisobutyronitrile(AIBN)as initiator,the molar ratio of nicotine to TFMAA of 1:3,and the dosage of acetonitrile of 60 mL,the prepared NMIPs had better adsorption capacity,with the imprinting factor of 1.8.The adsorption performance of NMIPs was investigated by Scatchard analysis,it indicated that there were two types of binding sites with high and low affinity of adsorption in the NMIPs,and the maximum apparent binding amount was 28.56 mg/g.When the NMIPs were used to purify nicotine from tobacco regrilling tail gas and the volatile oil of fresh tobacco leaves,the relative contents of nicotine increased from 63.58%to 89.78%and 89.39%to 95.71%,respectively.