Abstract: Molecularly imprinted polymer microspheres (MIPMs) were prepared by precipitation polymerization of methacrylic acid (MAA) and ethylene dimethacrylate (EDMA) using cholesterol (CHO) as template molecule in toluene-acetonitrile mixed solvent (9:1, j). The MIPMs were investigated in equilibrium binding experiment and Scatchard analysis to evaluate the binding characteristics and recognition mechanism of MIPMs in aqueous solution. Scatchard analysis showed that two classes of binding sites were produced in the polymer matrix under the studied concentration. Their dissociation constant (Kd) and apparent maximum binding capacity (Qmax) were 0.86 mmol/L, and 80.4 mmol/g for high affinity binding sites and 0.39 mmol/L and 61.6 mmol/g for low affinity binding sites. The CHO imprinted polymer micro-spheres synthesized in this method had better performance and could be used for separation, enrichment and analysis of CHO.

Key words: cholesterol, molecularly imprinted polymer microspheres, precipitation polymerization

摘要： 以胆固醇为模板分子、甲基丙烯酸为功能单体、乙二醇二甲基丙烯酸酯为交联剂，在甲苯-乙腈(9:1, j)混合溶剂中沉淀聚合制备了分子印迹聚合物微球. 采用平衡结合法和Scatchard模型评价了该聚合微球的结合性，考察了其吸附行为. 结果表明，胆固醇分子印迹聚合微球中形成两类不同的结合位点，得到高亲和性结合位点的离解常数和最大表观吸附量分别为0.86 mmol/L和80.4 mmol/g，低亲和性结合位点解离常数和最大表观吸附量分别为0.39 mmol/L和61.6 mmol/g. 此方法合成的分子印迹微球对胆固醇有较好的结合性能，可用于胆固醇的分析检测.

关键词: 胆固醇, 分子印迹聚合微球, 沉淀聚合