没食子酸磁性表面分子印迹聚合物的制备与选择性识别性能

羟基苯甲酸类化合物用途广泛,极性较强,在复杂水溶液体系中这些类似物的分离纯化与分析非常困难。 本文以磁性Fe₃O₄纳米颗粒为载体,没食子酸(GA)为模板分子,制备了磁性表面分子印迹聚合物(MIP)。 利用透射电子显微镜、红外光谱、磁强测定等检测手段对MIP进行了结构表征。 并对其吸附性能进行研究,比较了该MIP对GA及其它3种结构类似物的吸附性能差异。 结果表明,制备的以GA为模板的磁性分子印迹聚合物为核壳球形结构,键合牢固,对GA的吸附动力学符合准二级动力学方程模型,吸附过程属于Langmuir单分子层吸附。 该聚合物对GA表现出优异的选择性识别能力,其吸附量(318 K时37.736 mg/g)远远高于结构类似物。 该磁性分子印迹聚合物对模板分子不仅具有特异识别能力,而且能够磁控分离,分离效率高,可用于固相萃取。

Preparation and Selective Recognition Property of Magnetic Surface Molecularly Imprinted Polymers with Gallic Acid as Template

Hydroxybenzoic acid compounds are used widely and have strong polarity. The separation, purification and analysis of their analogues in complex aqueous solution are very difficult. In this paper, magnetic surface molecularly imprinted polymer(MIP) was prepared using nano magnetic Fe₃O₄ as the carrier and gallic acid(GA) as the template molecule, and characterized by transmission electron microscopy, infrared spectroscopy and magnetic intensity measurement. Then its adsorption properties and adsorptive selectivity were studied by the static adsorption and dynamic adsorption experiments to compare the adsorption properties of GA on MIP with those of 2,4-dihydroxybenzoic acid, salicylic acid and benzoic acid. The results show that the MIP with GA as the template has a core-shell structure with a strong bonding effect, the adsorption process belongs to Langmuir monolayer adsorption and the adsorption kinetics can satisfy the pseudo-second-order kinetic equation model. The MIP exhibits an excellent selectivity for GA, and its adsorption capacity(37.736 mg/g at 318 K) is much higher than those of other structural analogues. The MIP prepared by this method can not only recognize the template molecule, but also be magnetically controlled. The high separation efficiency is applicable to the solid phase extraction.