混合阳离子交联剂甲基丙烯酸海藻酸盐微球的构建及其性能研究

Preparation and Properties Evaluation of Methacrylic Alginate Gell Beads Cross-Linked by Mixed Metal-Cation

本研究旨在制备既有一定机械强度又能保持良好渗透性的海藻酸盐凝胶小球,从而可更好地应用于组织工程领域。通过海藻酸盐中的羧基和甲基丙烯酸中的氨基作用生成酰胺键的反应,将甲基丙烯酸引入藻酸盐长链,然后利用热反应的原理,通过甲基丙烯酸中的双键聚合,使藻酸盐长链的强度得以增强,最后将氯化钙和氯化钡分别以7∶3、5∶5、3∶7比例混和作为阳离子交联剂,形成海藻酸盐凝胶小球,并进一步研究其压缩模量和渗透性。结果表明以[Ba2+:Ca2+=5∶5]作为混合阳离子交联剂制作的凝胶小球,压缩模量为189.7kPa,对24kDa的胰蛋白酶分子的渗透性最好,对67kDa的牛血清白蛋白分子具有截留作用。以[Ba2+:Ca2+=5∶5]作为混合阳离子交联剂与甲基丙烯酸改性的海藻酸盐形成的凝胶小球,与其他比例相比较,强度和渗透性均显示出最佳特性,可以更好地用于组织工程支架材料以及细胞培养的包埋材料。

The aim of this study was to obtain the alginate gels which could have proper compressive strength and ex- cellent permeability for cell proliferation and could have more promising potentials in the application of tissue engi- neering. Through the reaction of the carboxyl of the alginate and the amino of methacrylic acid, methylaerylie was generated into alginate long chain which could be enhanced by the polymerization of double bond under thermal reac tion condition. And then alginate gel beads were prepared using the mixture of calcium chloride and barium chloride solution as cationic crosslinker, and the compressive modulus and permeability of the prepared alginate gel beads were investigated. When the ratio of barium ions to calcium ions was 5 ~5, the compression modulus was 189.7kPa, and it showed the best permeability for trypsin with molecular weight of 24kDa and entrapment effect for bovine ser- um albumin with molecular weight of 67kDa. Compared to compositions of other ratios, the alginate gel beads made in 5：5 mixture indicated excellent compressive modulus and permeability. These results indicated that the alginate hydrogel beads with the ratio of barium ions to calcium ions being 5 =5 have a potential application in tissue engineer ing as a support material and encapsulating materials in cell culture.