沉淀聚合法制备孔雀石绿分子印迹聚合物微球

Preparation of malachite green molecularly imprinted polymer microspheres via precipitation polymerization

以孔雀石绿为模板分子,甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,偶氮二异丁腈为引发剂,乙腈为溶剂,采用沉淀聚合法制备了孔雀石绿分子印迹聚合物微球。紫外光谱研究表明模板分子和功能单体通过氢键作用形成1 2型配合物;利用静态平衡吸附实验研究了印迹聚合物对模板分子的结合能力,Scatchard分析表明,印迹聚合物中存在两类不同的结合位点,高亲和性位点的平衡离解常数Kd1=11.223μg.mL-1,最大表观结合量Qmax1=4.45×102μg.g-1;低亲和性位点的平衡离解常数Kd2=156.25μg.mL-1,最大表观结合量Qmax2=5.033×103μg.g-1。

Molecularly imprinted polymer （MIP） microspheres were prepared via precipitation polymerization with malachite green（MG） as template, a-methacrylic acid（MAA） as functional monomer, ethylene glycol dimethacrylate（EGDMA） as crosslinker and acetonitrile as solvent. The interaction between the MG and MAA was determined by UV-Vis adsorption spectrum. The results showed that the MG-MAA complex of 1：2 stoichiometric mole ratio was obtained by cooperative hydrogen bonds. Equilibrium adsorption experiment was carried out to examine the binding ability of the MIP microspheres. Scatchard analysis showed that two classes of binding sites were formed in the imprinted polymers.The calculated dissociation constant Kd1 and the apparent maximum binding capacities Qmax1 for the high affinity sites were 11.223 μg·mL-1 and 4.45× 10^2 μg·mL-1, while Kd2 and Qmax2 for the low affinity sites were 156.25 μg·mL-1 and 5.033×10^3μg·mL-1, respectively. Key words： malachite green; molecularly imprinted polymers; precipitation polymerization