摘要
为快速筛选及确定合适的预聚体系,以高效制备对茶叶等食品中残留的溴氰菊酯具有特异识别能力的分子印迹聚合物,以溴氰菊酯为模板,采用Materials Studio软件和紫外光谱对预聚体系中功能单体和溶剂进行种类筛选及配比确定,辅助溴氰菊酯分子印迹聚合物的合成设计。对模板与不同功能单体预聚体系的结合能计算和光谱分析结果均表明溴氰菊酯与丙烯酰胺能形成更为稳定的复合物,且以乙腈为溶剂更有利于溴氰菊酯分子印迹聚合物的制备。差示紫外光谱计算进一步得出当溴氰菊酯与丙烯酰胺的化学配位比n=4时,可在乙腈溶液中形成稳定的预聚体系,其结合常数为6.614×10~5。基于上述结果,采用沉淀聚合法正交优化制备溴氰菊酯分子印迹聚合物,扫描电镜和静态平衡吸附试验结果表明所制备聚合物具有良好的多孔结构和特异吸附性,印迹因子为2.269,对3种结构类似物的分离因子均大于3.2。研究结果表明分子模拟和光谱分析方法对分子印迹预聚体系筛选和聚合物合成设计具有重要的指导意义。
To efficiently prepare decamethrin molecular(DM)imprinted polymers,the molecular dynamics simulation and ultraviolet spectrum were involved to study the preassembled system of DM and functional monomers in this paper.The binding energy(ΔE)between DM and three different functional monomers(acrylic acid,AA;acrylamide,AM;methacrylic acid,MAA)in different solvents(n-hexane,chloroform,acetone and acetonitrile)were calculated by molecular dynamics simulation.Results showed that the AM monomer and acetonitrile solvent had the highest stabilization energy for the pre-polymerization adducts.Additionally,the polymer obtained from the molar ratio of DM to AM at 1:4 to 1:6 may be more stable.Ultraviolet spectrum analysis results showed that there was strong interaction between DM and AM,the red shift degree of ultraviolet spectrum maximum absorption peak followed the order:AM>AA=MAA,and then indicated that AM was most suitable monomers for DM molecular imprinted polymers,which was consistent with the predictions based on the computer simulation.Differential ultraviolet spectrum showed that when acetonitrile used as solvent,one DM molecule could be combined with AA monomer in the ratio of 1:3 or AM monomer in the ratio of 1:4.However,it was difficult for DM to form stable complex with MAA because the fitting correlation coefficient of the equation was less than 0.86.Best performance was observed when chemical coordination ratio(n)between DM and AM was equal to 4,at this time,the fitting correlation coefficient of the equation was 0.997 3,and the binding constant K was 6.614×10^5.Based on the above computer simulation and ultraviolet spectrum analysis results,the molecularly imprinted polymers of DM were synthesized by the precipitation polymerization method with the AM as the functional monomer,and its synthetic formula was optimized through orthogonal experiment design.Then,the optimum imprinting conditions were established:1 mmol DM as the template molecule,4 mmol AM as the functional monomers,40 mL acetonitrile as the so
作者
李璐
周刘梅
解新安
李雁
Li Lu;Zhou Liumei;Xie Xinan;Li Yan(College of Food Science,South China Agricultural University,Guangzhou 510640,China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2019年第1期269-277,共9页
Transactions of the Chinese Society of Agricultural Engineering
基金
广州市科技计划项目(20160701140)
国家自然科学基金项目(31501471)
关键词
农药
分子动力学
紫外可见光谱
pesticide
molecular dynamics
ultraviolet visible spectroscopy
