为了改善海藻酸盐凝胶的离子交联强度较低、含水量高、凝胶稳定性差等不足,通过在海藻酸盐凝胶体系中添加少量纤维素醚(如羟乙基纤维素等)并使用戊二醛交联的方法,制备了互穿网络改性大分子及乳液双印迹海藻酸钙凝胶微球.微球机械强度和在0.9%氯化钠溶液中的抗溶胀性均有提高,振荡实验破损比例由24.4%降低为9.84%.红外光谱表明,改性组分戊二醛和羟乙基纤维素之间形成新的化学键,构成互穿网络结构.重结合实验表明,经过互穿网络改性的双印迹微球的印迹效率由2.19提高到2.70.离子交换色谱实验证实,改性微球的重结合分离系数由1.478提高到18.88.印迹重结合行为发生变化的原因可以归结为其价交联的互穿网络的形成和疏水性微环境的影响.共价交联的互穿网络可在一定程度上提高微球印迹结构的稳定性,增强对模板分子的特异性重结合能力.
In order to improve crosslinking strength and hydrogel stability, cellulose ether was introduced into cal- cium alginate and crosslinked to form interpenetrating networks (IPNs). Protein and emulsion dually imprinted calcium alginate microspheres were prepared with the modified hydrogel and were applied for selective rebinding. The microspheres were found to be more mechanically stable and more resisting to 0.9% sodium chloride aqueous solution, and the damage ratio was reduced from 24.4% to 9.84% according to oscillation test. The infrared spectra measurement indicated that new chemical bonds were formed between glutaraldehyde and cellulose, which con- structed the interpenetrating networks. Protein molecule imprinting and rebinding experiments were performed and imprinting efficiency was increased from 2.19 to 2.70 towards target molecular in the microspheres modified by IPNs. An improvement in separation factor from 1.478 to 18.88 was confirmed by ion-exchange chromatography experiments. The above results could be ascribed to the compact network structure due to the association of stronger covalent crosslinkages in the IPNs and the hydrophobic micro-environment. The IPNs enhance the imprint structure stability and increase rebinding specificity.