双酚A印迹聚合微球制备、识别机理及固相萃取研究

Preparation, recognition mechanism and solid phase extraction of bisphenol A molecularly imprinted microspheres

以双酚A(BPA)为模版分子,4-VP为功能单体,Trim为交联剂,采用沉淀聚合法合成BPA分子印迹聚合微球(MIPs)。通过紫外和红外光谱考察BPA与4-VP相作用机理,扫描电镜(SEM)观察MIPs的表观形态;结果表明BPA和4-VP之间形成了氢键并且以1:2的比例相结合,MIPs表面光滑呈球状。吸附实验显示MIPs具有较高的特异性,吸附能力远高于非分子印迹聚合物(NIPs)。对吸附曲线进行Scatchard分析,在MIPs上形成了均匀的BPA吸附位点,其最大表观吸附量(Qmax)和平衡离解常数(Kd)分别为28.83μmol/g和0.3112μmol/L。固相萃取(SPE)分析表明MIPs对BPA具有较高选择性和吸附容量,可以用于分离、富集和检测复杂食品样品中的BPA。

Bisphenol A （2,2-bis （4-hydroxyphenyl） propane, BPA） molecularly imprinted polymers （MIPs） were synthesized by precipitation polymerization method with BPA as the template molecule, 4-VP as the functional monomer and TRIM as the cross-linker. Interaction between BPA and 4-VP was investigated by UV and FT-IR techniques. The morphology of MIPs was observed with scanning electron microscope （SEM）. The results showed that a 1：2 cooperative H-bonding interaction was the main interaction between BPA and 4-VP in the pre-polymerization, the morphology of MIPs was the uniform and irregularly particles with smooth surface. Adsorption results revealed that the MIPs have a higher affinity and selectivity for BPA than non-molecularly imprinted polymers （NIPs）. Scatchard analysis indicated that the homogeneous binding sites of BPA were formed in MIPs, the maximum adsorption amounts and the equilibrium dissociation constant were Q max =28.83 μmol/g, K d =0.3112 μmol/L, respectively. SPE analyses showed thatMIPs had more efficiency, higher specificity and selectivity for BPA; so it could be applied for separation, concentration and determination of BPA from complicated food samples.