微球形磺胺脒分子印迹聚合物的制备及其性能

Synthese and Molecular Recognition Characteristics of Sulfaguanidine Imprinted Polymer Microspheres

建立了以沉淀聚合方式制备磺胺脒分子印迹聚合物微球的方法,其中磺胺脒用作模板分子,甲基丙烯酸用作功能单体,二甲基丙烯酸乙二醇酯用作交联剂.对印迹微球的选择性和吸附性能进行了研究.优化的反应物用量是:磺胺脒0.05mmol,甲基丙烯酸0.2mmol,二甲基丙烯酸乙二醇酯1mmol(摩尔比1∶4∶20).在此条件下,溶剂乙腈用量是5mL,引发剂偶氮二异丁腈用量是10mg,在60℃下热引发聚合反应24h,等温静态平衡实验结果表明,该印迹聚合物与相应的空白聚合物相比具有高的选择性和亲和性.Scatchard模型分析结果表明,该印迹聚合物在印迹过程中形成了2类不同的结合位点,高亲和性位点离解常数和最大表观吸附量分别为1.932mmol/L和196.06μmol/g,低亲和性位点离解常数和最大表观吸附量分别为23.843mmol/L和1 449.04μmol/g.印迹聚合物微球重复使用10次吸附性能无显著下降,具有作为固相萃取柱填料使用的潜力.

A method preparing sulfaguanidine （SG） imprinted polymer microspheres by precipitation polymerization was developed, in which SG, methacrylic acid （MAA） and ethylene glycol dimethacrylate （EGDMA） were used as template molecule, functional monomer and crosslinker,respectively. The selectivity and adsorption properties of these microspheres were investigated. The optimized amounts of reactants were 0.05 mmol SG,0.2 mmol MAA,and 1 mmol EGDMA （molar ratio 1 ： 4 ：20）. Under this condition, the volume of acetonitrile as solvent was 5 mL and the amount of azobisisobutyronitrile （AIBN） as initiator was 10 mg. The microspheres were polymerized at 60 ℃ for 24 h. The result of static equilibrium isotherm experiment revealed that molecularly imprinted polymer （MIP） had high bingding affinity and selectivity to sulfamidine. Scatchard analysis showed that there were two different kinds of binding sites in the MIP. The dissociation constant and the maximum adsorption capacity were 1. 932 mmol/L and 196.06 μmol/g for the high affinity site,and they were 23. 843 mmol/L and 1 449.04 μmol/g for the low affinity site,respectively. The MIP microspheres could be reused ten times without significant decrease on adsorption properties,as well used in solid phase extraction column as fillers..