对三聚氰胺(MEL)为模板,丙烯酰胺(AM)为功能单体,乙二醇二甲基丙烯酸酯(EGDMA)为交联剂的分子印迹组装体系分子模拟分析,辅助设计了三聚氰胺分子印迹聚合物,分析其印迹机理。结果表明:组装体系中发生相互作用的基团主要为MEL分子的三个氨基氢和三嗪环上的三个氮,AM中的氨基氢和羰基氧,EGDMA中羰基氧。AM的羰基氧比EGDMA对质子的亲和力强,易于形成氢键。AM中两个氨基氢靠近羰基的氨基质子形成氢键能力强。AM与EGDMA形成复合物的AVG△E均高于对应模板复合物体系,EGDMA比模板更有利于竞争单体。MEL与AM、EGDMA相互作用主要形成MEL-AM-EGDMA复合物,其次为MEL-3AM。最终MIPs中对MEL具有特异性识别的作用位点为AM的氨基氢和羰基氧和EGDMA中的羰基氧。选定c(MEL)∶c(AM)∶c(EGDMA)=1∶1∶10,即浓度分别为:c(MEL)=4 mmol/L,c(AM)=4 mmol/L,c(EGDMA)=40 mmol/L作为最优MEL-MIPs制备基础浓度。
By the molecular simulation analysis of molecularly imprinted assembly system,which using melamine MEL as template molecular,acrylamide AM as functional monomer and ethylene glycol dimethacrylate EGDMA as cross-linking agent,the MEL molecularly imprinted polymer was aided designed and the molecularly imprinted mechanism of MEL was analyzed. The results show that : the main interaction groups are three amino hydrogen of MEL and three nitrogen atoms in triazine ring, amino hydrogen and carbonyl oxygen of AM and carbonyl oxygen of EGDMA. The affinity of carbonyl oxygen of AM for proton is stronger than carbonyloxygen of EGDMA,it is easy to form hydrogen bond. Of the two amino hydrogen of AM,the amino proton near carbonyl has strong ability to form hydrogen bond. Both AVG △E of compounds formed by AM and EGDMA are higher than corresponding template compound system,EGDMA is better for winning monomer than template. The interaction of MEL, AM and EGDMA mainly form MEL- AM-EGDMA compound, followed by MEL-3 AM. Ultimately, the action sites of MIPs which have specific recognition on MEL are amino hydrogen and carbonyl oxygen of AM and carbonyl oxygen of EGDMA. c(MEL) :c(AM) :c(EGDMA)= 1 :1 :10,that is to say c(MEL) = 4 mmol/L,(AM) = 4 mmol/L and c(EGDMA) = 40 mmol/L are finally selected as the basic concentration for the preparation of best MEL-MIPs.