α-生育酚分子印迹微球的制备与吸附性能评价

Synthesis of molecularly imprinted microspheres of α-tocopherol and evalua-tion of their absorption property

中文关键词:  α-生育酚  分子印迹聚合物微球  沉淀聚合法

英文关键词:α-tocopherol  molecularly imprinted polymer microspheres  precipitation polymerization

中文摘要:

      目的 采用沉淀聚合法制备α-生育酚分子印迹微球及条件优化, 并对其吸附性能进行评价。方法 以α-生育酚为印迹分子, 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, 在乙腈溶液中用沉淀聚合法合成了α-生育酚分子印迹聚合物微球, 采用扫描电镜观察聚合物的形貌特征, 并对影响其形貌的因素进行优化。结果 最佳合成条件为: 乙腈为反应溶剂, 反应温度为60 ℃, 模板用量为0.20 mmol, 引发剂用量为40 mg, 转速为100 r/min。静态吸附试验结果表明, α-生育酚分子印迹聚合物微球具有两种不同的结合位点, 结合位点的平衡吸附常数和最大平衡结合量分别为Kd1=0.995 mmol/L, Qmax1=22.420 μmol/g; Kd2=0.458 mmol/L, Qmax2=15.865 μmol/g。结论 优化条件下的分子印迹微球形貌规整, 粒径约为200 nm, 并对α-生育酚具有较好的吸附性能。

英文摘要:

      Objective To prepare molecularly imprinted polymer (MIP) microspheres of α-tocopherol by precipitation polymerization and the conditions optimization, moreover, the products absorption property were evaluated. Methods The MIPs of α-tocopherol were synthesized by precipitation polymerization by using methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) and acetonitrile as functional monomer, cross-liker and solution, respectively. The morphology of the MIP microspheres was characterized by scanning electron microscope (SEM) and the corresponding effect factors were optimized. Results The optimal conditions were as follows: acetonitrile as solvent; reaction temperature at 60 ℃; 0.20 mmol template molecule (α-tocopherol) and 40 mg initiator (azobisisobutyronitrile, AIBN); and stirring speed at 100 r/min. The absorption property and the binding characteristics of the MIPs were evaluated by equilibrium binding experiment and Scatchard analysis. The results showed that two classes of binding sites were produced in the polymer matrix, their dissociation constant (Kd) and the apparent maximum equilibrium binding capacity (Qmax) were 0.995 mmol/L, 22.420 μmol/g for high affinity binding sites and 0.458 mmol/L, 15.865 μmol/g for low affinity binding sites. Conclusion Under optimal conditions, the α-tocopherol MIPs showed good morphology of microsphere with particle size around 200 nm and good absorption of α-tocopherol.