Wu Xiangyang, Goswami Kisholoy, Shimizu Ken D
Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA.
J Mol Recognit. 2008 Nov-Dec;21(6):410-8. doi: 10.1002/jmr.912.
In this study, molecularly imprinted polymers (MIPs) prepared using a multifunctional and a monofunctional monomer were compared with respect to their affinities, selectivities, and imprinting efficiencies for organophosphates. This is of interest because multifunctional monomers have higher affinities than traditional monofunctional monomers for their target analytes and thus should yield MIPs with higher affinities and selectivities. However, polymers containing multifunctional monomer may also have a higher number of unselective, non-templated binding sites. This increase in background binding sites could lead to a decrease in the magnitude of the imprinting effect and in the selectivity of the MIP. Therefore, phosphate selective imprinted and non-imprinted polymers (NIPs) were prepared using a novel multifunctional triurea monomer. The binding properties of these polymers were compared with polymers prepared using a monofunctional monourea monomer. The binding affinities and selectivities of the monomers, imprinted polymers, and NIPs were characterized by NMR titration, binding uptake studies, and binding isotherms. MIPs prepared with the triurea monomer showed higher binding affinity and selectivity for the diphenylphosphate anion in organic solvents than the MIPs prepared with the monofunctional monomer. Surprisingly, the binding properties of the NIPs revealed that the polymers prepared using the multifunctional and monofunctional monomers were very similar in affinity and selectivity. Thus, the multifunctional monomers increase not only the affinity of the MIP but also enhance the imprinting effect.
在本研究中，对使用多功能单体和单功能单体制备的分子印迹聚合物（MIP）在对有机磷酸酯的亲和力、选择性和印迹效率方面进行了比较。这一点很重要，因为多功能单体对其目标分析物的亲和力高于传统单功能单体，因此有望产生具有更高亲和力和选择性的MIP。然而，含有多功能单体的聚合物也可能具有更多非选择性、非模板化的结合位点。这种背景结合位点的增加可能导致印迹效应的幅度和MIP的选择性降低。因此，使用新型多功能三脲单体制备了对磷酸盐具有选择性的印迹和非印迹聚合物（NIP）。将这些聚合物的结合特性与使用单功能单脲单体制备的聚合物进行了比较。通过核磁共振滴定、结合摄取研究和结合等温线对单体、印迹聚合物和NIP的结合亲和力和选择性进行了表征。与使用单功能单体制备的MIP相比，用三脲单体制备的MIP在有机溶剂中对磷酸二苯酯阴离子表现出更高的结合亲和力和选择性。令人惊讶的是，NIP的结合特性表明，使用多功能和单功能单体制备的聚合物在亲和力和选择性方面非常相似。因此，多功能单体不仅增加了MIP的亲和力，还增强了印迹效果。
