Institute of Analytical and Bioanalytical Chemistry, University of Ulm, Ulm, Germany.
Anal Chim Acta. 2012 Sep 26;744:68-74. doi: 10.1016/j.aca.2012.07.020. Epub 2012 Aug 1.
In molecular imprinting the porogen plays a decisive role, as it not only affects the physical properties of the resulting polymer including its porosity, the specific surface area, and the swelling behavior, but also governs the stability of the prepolymerization complex, which in turn decisively determines the recognition properties of the resulting molecularly imprinted polymer (MIP). In this study, the influence of the porogen on the selectivity of MIPs was investigated. Therefore, bulk MIPs against 4-nitrophenol using 4-vinylpyridine (4-VP) as functional monomer and ethylene glycol dimethacrylate (EDMA) as crosslinker were prepared in acetonitrile and chloroform. The recognition properties of both MIPs were evaluated during chromatographic studies using the respective porogenic solvents as mobile phase for both MIPs. Along with the characterization of the morphology of the obtained polymers via SEM and BET analysis, the beneficial nature of chloroform as porogen for imprinting 4-NP was experimentally demonstrated and verified by findings obtained from complementary molecular dynamics simulations. Moreover, the application of chloroform as mobile phase for the MIP prepared in acetonitrile and vice versa clearly demonstrated the dependence of the resulting recognition properties on the selection of the mobile phase.
在分子印迹中，致孔剂起着决定性的作用，因为它不仅影响聚合物的物理性质，包括其孔隙率、比表面积和溶胀行为，还控制着预聚合配合物的稳定性，而这反过来又决定了所得分子印迹聚合物（MIP）的识别性能。在这项研究中，研究了致孔剂对 MIP 选择性的影响。因此，使用 4-乙烯基吡啶（4-VP）作为功能单体和乙二醇二甲基丙烯酸酯（EDMA）作为交联剂，在乙腈和氯仿中制备了块状 MIP 对 4-硝基苯酚。在使用各自的致孔溶剂作为两种 MIP 的流动相的色谱研究中，评估了两种 MIP 的识别性能。除了通过 SEM 和 BET 分析对获得的聚合物的形态进行表征外，还通过互补的分子动力学模拟获得的结果，实验证明了氯仿作为印迹 4-NP 的致孔剂的有益性质。此外，将氯仿用作在乙腈中制备的 MIP 的流动相，反之亦然，这清楚地表明了所得识别性能对流动相选择的依赖性。
