3-吲哚羧酸的性质对其印迹聚合物印迹效率的影响

Influence of Properties of Indole-3-Carboxylic Acids on Their Molecular Imprinting Efficiency

以3-吲哚丙酸(IPA)和3-吲哚丁酸(IBA)为模板分子,4-乙烯基吡啶(4-Vpy)为功能单体,乙二醇二甲基丙烯酸酯为交联剂,乙腈为致孔剂,利用非共价本体聚合法,制备了印迹聚合物P(IPA)和P(IBA),并用色谱法评价了其分子识别性能。结果表明,P(IPA)和P(IBA)分别对IPA和IBA具有分子识别能力,静电作用在其分子识别过程中起重要作用。此外,对P(IPA)、P(IBA)和同样条件下制备的3-吲哚乙酸(IAA)印迹聚合物P(IAA)的分子识别能力进行了比较,乙腈为流动相时,P(IAA)、P(IPA)和P(IBA)对各自模板分子的印迹因子IF值分别为大于6.00,4.27和2.28,即随着3-吲哚羧酸羧基碳链的增长,其印迹效率降低。结果表明,在P(IPA)和P(IBA)中,分别存在与对应的模板分子互补的印迹空穴;随着3-吲哚羧酸酸性的降低,印迹聚合物的印迹效率降低。

Molecular recognition abilities of molecularly imprinted polymers of 3-indolepropionic acid（P（IPA））and 3-indolybutyric acid（P（IBA））were prepared using 3-indolepropionic acid and 3-indolybutyric acid as template molecule,respectively,4-vinylpyridine（4-Vpy）as functional monomer,ethyleneglycol dimethacrylate（EGDMA）as cross-linker and acetonitrile as porogen by bulk non-covalent imprinting technique.The molecular recognition performances were evaluated by high performance liquid chromatography. The results showed that both P（IPA）and P（IBA）exhibited molecular recognition ability for IPA and IBA,respectively,in the mobile phase of acetonitrile.The affinity and specificity of the two polymers reduced in acetonitrile/HAc mobile phase,which proved that electrostatic interaction played an important role in the molecular recognition processes.In addition,the comparison of molecular recognition ability was made among P（IPA）,P（IBA）and P（IAA）,which was synthesized under the same conditions as P（IPA）and P（IBA） except for the template molecule.The imprinting factors（IF）were larger than 6.00,4.27 and 2.28 for IAA,IPA and IBA,respectively,in acetonitrile mobile phase,i.e.the imprinting efficiency decreased with the increase of the carbon-number in the indole-3-carboxylic chain.The study confirmed that there were cavities with the shape and orientation of the functional groups complementary to those of IPA and IBA,respectively,in P（IPA）and P（IBA）.And the molecular imprinting efficiency reduced with the decrease of the acidity of the indole-3-carboxylic acid.