环氧功能化双功能磁性分子印迹聚合物的合成及其在多糖吸附中的应用

Synthesis and applications of epoxy-functionalized bi-functional magnetic molecularly imprinted polymers for polysaccharide adsorption

以淀粉为模板,以3-氨基苯硼酸(APBA)和2-丙烯酰胺-2-甲基丙磺酸(AMPS)为功能单体,以过硫酸铵(APS)为引发剂,在水溶液中成功合成了一种识别多糖的双功能分子印迹聚合物(Bi-MMIPs)。采用透射电镜、扫描电镜、傅里叶变换红外光谱等考察了Bi-MMIPs的合成效果。通过吸附试验深入研究了Bi-MMIPs对淀粉的吸附和识别特性。结果表明:Bi-MMIPs成功负载了两种功能单体,且对多糖(淀粉)具有很强的吸附亲和力和特异性识别能力,饱和吸附量达到13.88mg/g;对于葡聚糖(Mr5000Da和70000Da)的选择性系数分别为2.67和3.77;此外,Bi-MMIPs的印迹因子(α)达到了3.04,且易于再生。在机理上,APBA和AMPS分别提供可逆共价键和氢键,在合成双功能单体中表现出协同效应,可以有效改善模板分子结合位点的空间排列。

A polysaccharide-imprinted nanoparticle composite material with bi-functional monomers molecularly imprinted polymers (Bi-MMIPs) was successfully synthesized in aqueous solution by using starch as the template, 3-aminobenzeneboronic acid (APBA) as the functional monomer, 2-acrylamide-2-methylpropanesulfonic acid (AMPS) as the co-functional monomer, and ammonium persulfate (APS) as the initiator. Transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier-transform infrared (FT-IR) spectroscopy were used to characterized Bi-MMIPs. The adsorption and recognition characteristics of Bi-MMIPs for starch were investigated in detail by using the static method, dynamic method, and competitive adsorption experiments. The TEM, SEM and FT-IR results showed that the two functional monomers were loaded on the surface of Bi-MMIPs. Bi-MMIPs possessed very strong adsorption affinity and specific recognition for starch. The saturated adsorption capacity reached 13.88 mg/g, and the selectivity coefficients relative to glucosans M r 5 000 Da and 70 000 Da were 2.67 and 3.77, respectively. Despite the imprinting factor of Bi-MMIPs (α=3.04), Bi-MMIPs were regenerated easily and exhibited excellent recognition, selectivity, and reusability for adsorbing starch. To elucidate the mechanism, APBA and AMPS showed synergy effect in synthesizing bi-functional monomers by providing reversible covalent bonds and hydrogen bonds, respectively, which could effectively enhance the spatial arrangement of combining sites for template molecular.