N-烷基化壳聚糖/白芨多糖复合材料制备

Preparation of N-alkylated chitosan/Bletilla striata polysaccharide composites

首先通过席夫碱反应将十二醛与壳聚糖分子内部氨基连接,经还原制得N-烷基化壳聚糖,再通过元素分析,测定了N-烷基化壳聚糖的取代度。以N-烷基化壳聚糖、白芨多糖为原料,通过离子交联、冷冻干燥法制备了N-烷基化壳聚糖/白芨多糖复合冻干粉。对所制备冻干粉进行表征及性能测试,探究了复合冻干粉作为止血材料应用的可能性。结果表明,冻干粉可吸收自身重量2~3倍的水,降解速率与白芨多糖含量呈正相关,抑菌性与N-烷基化壳聚糖含量呈正相关。复合冻干粉粒径与血小板相近,表面呈现凹凸多孔结构,吸水性较强,降解速率适宜,抑菌性较强。综合考虑各项性能参数,N-烷基化壳聚糖与白芨多糖比例为4∶1时,复合冻干粉性能最佳,具备作为止血材料应用的潜力。

N-alkylated chitosan was synthesized by reducing dodecyl aldehyde to chitosan via Schiff base reaction.The degree of substitution of N-alkylated chitosan was determined by elemental analysis.N-alkylated chitosan and Bletilla striata polysaccharide were used as raw materials to prepare N-alkylated chitosan/Bletilla striata polysaccharide composite freeze-dried powder by ion crosslinking and freeze-drying method.The characterization and performance test of the prepared lyophilized powder were carried out,and the possibility of application of the composite lyophilized powder as a hemostatic material was explored.The results showed that the lyophilized powder could absorb water of 2~3 times its own weight,and the degradation rate was positively correlated with the content of Bletilla striata polysaccharide,and the bacteriostatic property was positively correlated with the N-alkylated chitosan content.The particle size of the composite lyophilized powder is similar to that of platelets,and the surface has a concave and convex porous structure,which has strong water absorption,suitable degradation rate and strong antibacterial activity.Considering various performance parameters,the ratio of N-alkylated chitosan to white peony polysaccharide is four to one.The composite lyophilized powder has the best performance and has the potential to be used as a hemostatic material.