A novel thermo⁃sensitive polymer N⁃acetyl glycol chitosan ( NAGC ) by N⁃acetylation of glycol chitosan with acetic anhydride was prepared. The chemical structure, thermo⁃sensitive property, morphology and in vitro drug release properties of NAGC hydrogel were investigated by means of 1 H NMR, FTIR, tube inverting method, SEM and UV⁃Vis spectroscopy. The results show that the degree of acetylation ( DA ) of NAGC is increased along with the increase of the feed molar ratio of acetic anhydride to glycol chitosan and re⁃action time. NAGC hydrogel shows reversible thermo⁃sensitive sol⁃gel transition behavior, and the sol⁃gel tran⁃sition temperature is well controlled from 25 ℃ to 37 ℃ by controlling the DA and polymer concentration. NAGC hydrogels show macroporous structure with the pore size of 1—40 μm. The pores are well⁃interconnec⁃ted to each other and the pore size could be controlled by changing the DA and concentration of NAGC. NAGC hydrogel( DA=89�90%, 5%—7%, mass fraction) shows sustained release behavior for anticancer drug gem⁃citabine, and the release time could be controlled from 3 d to 5 d. NAGC shows great promise for various bio⁃medical applications, such as drug delivery and tissue engineering.%以乙二醇壳聚糖为原料，乙酸酐为酰化剂，通过N⁃乙酰化反应，制得了新型温敏性高分子乙酰化乙二醇壳聚糖．通过核磁共振氢谱（1 H NMR）、傅里叶变换红外光谱（ FTIR）及试管倒置法对乙酰化乙二醇壳聚糖的结构及温敏性进行了表征，通过扫描电子显微镜（ SEM）和紫外⁃可见分光光度计（ UV⁃Vis）对水凝胶的微观形貌和体外药物释放性能进行了研究．结果表明，随着反应时间和乙酸酐与乙二醇壳聚糖氨基摩尔比的增加，产物的乙酰度逐渐增加；乙酰化乙二醇壳聚糖溶液具有热可逆温敏性溶胶⁃凝胶转变行为，可以通过控制乙酰化乙二醇壳聚糖的乙酰度和溶液浓度，使溶胶⁃凝胶转变温度处于室温至体温（25～37℃）之间；乙酰化乙二醇壳聚糖水凝胶具有“高度孔隙化且孔隙之间相互连通”的结构特点，通过控制乙酰度和溶液浓度，可使其孔径大小处于1～40μm范围内；乙酰化乙二醇壳聚糖水凝胶的乙酰度为89�90％时，质量分数为5％～7％的水凝胶对抗癌药物吉西他滨具有缓释作用，载药凝胶的释药时间可达3～5 d．乙酰化乙二醇壳聚糖有望在药物释放及组织工程等领域得到广泛应用．
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