吲哚-3-乙酸分子印迹聚合物的合成及吸附性能分析

摘要

以吲哚-3-乙酸（indole-3-acetic acid，IAA）为模板、甲基丙烯酸为功能单体、乙腈为致孔剂，采用本体聚合法合成了对 IAA 有特异性识别的吲哚-3-乙酸分子印迹聚合物（IAA-MIP）。红外光谱分析表明，IAA 是以氢键形式结合在聚合物的空腔中。等温吸附线及 Scatchard 分析表明，洗脱模板后的 IAA-MIP 结合 IAA 的能力比空白印迹聚合物（NIP）强，且有2种结合方式，其解离常数分别为 K D1＝1·04×10－6 mol·L－1和 K D2＝9·23×10－6 mol·L－1，最大表观结合位点分别为 B max1＝0·10μmol·g－1和 B max2＝0·28μmol·g－1。对植物样品的固相萃取实验表明，洗脱模板后的IAA-MIP 对 IAA 具有较强的特异性吸附能力。%Using indole-3-acetic acid(IAA)as template and methacrylic acid as functional monomer and ace-tonitrile as porogen,indole-3-acetic acid molecular imprinted polymers(IAA-MIP)that had specific recognition to IAA were synthesized by bulk polymerization.Infrared spectroscopy indicated that IAA was hydrogen bond-ed in the cavity of the polymers.Adsorption isotherm and Scatchard analysis showed IAA-MIP removed tem-plate had higher affinity to IAA than non-imprinted polymers(NIP).There were two binding modes between IAA-MIP and IAA,the dissociation constants were K D1 = 1.04× 10 -6 mol·L-1 and K D2 =9.23× 10 -6 mol· L-1 ,the maximum apparent binding capacity were B max1 =0.10 μmol·g-1 and B max2=0.28 μmol·g-1 .Experi-ments of solid-phase extraction from plant sample solutions showed IAA-MIP removed template had specific ad-sorption ability for IAA.