麻黄碱印迹聚合物合成条件对其形态及结合特性的影响

印迹聚合物合成条件对聚合物性能的影响是分子印迹技术中的一项重要研究内容。以左旋麻黄碱为印迹分子,甲基丙烯酸为功能单体,使用不同的交联剂和致孔剂合成了印迹聚合物,并对所得到的印迹聚合物的比表面积、孔结构和结合特性进行了评价。研究结果说明合成的印迹聚合物对印迹分子具有很好的亲和能力及选择性。致孔剂可以影响聚合物比表面积的大小及单体组成。氯仿是甲基丙烯酸-乙二醇二甲基丙烯酸酯和甲基丙烯酸-季戊四醇三丙烯酸酯聚合链的良溶剂,导致了比表面积及孔容较小的聚合物结构；而以乙腈为致孔剂得到的聚合物有较大的比表面积。共聚物中羧基含量的测定结果也说明,在预聚溶液中单体浓度相同的条件下,以不同的致孔剂进行合成得到的聚合物中甲基丙烯酸的比例不同。聚合物的比表面积及单体浓度的差别都可能导致聚合物的结合容量不同。

Study of the Influence of Synthesis Conditions on the Morphology and Binding Property of (-)-Ephedrine Imprinted Polymers

Contribution of the synthesis parameters to the properties of the polymer is one of the major interests in the study of molecular imprinting technology. To have a better understanding of the influence of polymerization conditions on the polymer morphology and binding property, (-)-ephedrine imprinted polymers synthesized with different cross-linkers (ethylene glycol dimethacrylate (EDMA) and pentaerythritol triacrylate (PETRA)), porogens (chloroform and acetonitrile) and monomer concentrations were compared. The resulting polymers were characterized with their pore structure, texture and binding affinities by BET and equilibrium adsorption method. The selectivity of the polymer was evaluated with chromatographic (analysis.) The results suggested that CHCl_3 is a good solvent for methacrylic acid (MAA)-EDMA and MAA-PETRA polymer chains which resulted in smaller polymer surface area. Quantitative determinations of the carboxyl groups in the polymer indicated that polymers synthesized with the same pre-polymerization composition except porogen can have different concentrations of functional monomer in their structures. The study showed that porogen in the molecular (imprinting) synthesis can affect the morphology and composition of the polymers, which influence the binding affinity of the polymers.