水溶性O-羟乙基壳聚糖接枝聚乳酸的制备与表征

目的制备用于组织工程的水溶性O-羟乙基壳聚糖／聚乳酸共聚物纤维复合支架。方法首先采用壳聚糖与环氧乙烷反应制备水溶性O-羟乙基壳聚糖，然后以辛酸亚锡为催化剂，水溶性O-羟乙基壳聚糖为引发剂，采用本体封管聚合法，激发D，L-丙交酯开环聚合制备水溶性O-羟乙基壳聚糖-g-聚乳酸共聚物。分别用X射线衍射、红外光谱、扫描电镜和溶解实验对产物的结构与性能进行分析表征。结果改性后的水溶性O-羟乙基壳聚糖能明显提高溶解性能，降低结晶性能和氢键间的相互作用。结论通过改性，为得到水溶性O-羟乙基壳聚糖／聚乳酸共聚物奠定了有利条件，并且此共聚物具有较好的孔隙率和网状结构，这对作为药物支架是一个很好的应用。此外，改性后的共聚物易溶于一些常用的有机溶剂中，有利于以后在组织工程中进一步应用。

Synthesis and characterization of Water soluble O-hydroxyethyl chitosan graft polylactic acid

Objective To fabricate water-soluble O-hydroxyethyl chitosan/ploylactic acid fibers composite scaffold for tissue engineering. Methods First, the water-soluble O-hydroxyethyl chitosan was prepared by the reaction ofchitosan with ethylene oxide, then the body sealing tube polymerization, with stannous octoate as catalyst, water-soluble O-hydroxyeth-yl chitosan for initiator cause D, L-lactide ring-opening polymerization preparation of water-soluble O-hydroxyethyl chitosan-g-polylactic acid copolymer. Using X-ray diffraction, infrared spectrum and scanning electron microscopy and dissolving experiment were adopted to characterize and analyze the degraded products. Results The modification of the water-soluble O-hydroxyethyl chitosan can obviously improve the dissolution performance, reduce the crystallization properties and the hydrogen bonding interaction. Conclusion Water soluble O-hydroxyethyl ehitosan/polylactic acid copolymer can been obtained with the chemical modification, and then put into use in drug eluting stent because it has a good porosity and mesh. In addition, modified copolymer is soluble in some of the most common organic solvents, and it＇ s helpful in the further application in tissue engineering.