生物可降解温敏性物理交联水凝胶的研究进展

Biodegradable Thermosensitive Physically-Crosslinked Hydrogel:A Review

近年来,原位形成的水凝胶体系已有诸多报道,通过溶剂交换、紫外线照射、离子浓度、pH值和温度的改变可原位诱导凝胶化转变。温敏性凝胶体系通常具有微妙的疏水-亲水两亲性平衡,在不需要有机溶剂、偶联剂和其它外界刺激的条件下,仅通过改变环境温度即可触发凝胶化相转变。生物可降解的温敏性水凝胶具有广阔的应用前景,既能作为药物缓释与输送的载体,也可用作组织再生的支架等生物医学材料。文中根据凝胶基体共聚物拓扑结构的不同,详细综述了近年生物可降解温敏性物理交联水凝胶的研究进展,及其化学物理结构与凝胶化行为、凝胶特性之间的内在联系。

In recent years,the in-situ formed hydrogel systems were reported in many literatures.It was reported that several mechanisms can lead to in-situ gelation of block copolymers,such as solvent exchanging,UV-irradiation,ionic cross-linking,changes of pH and temperature.Generally,the thermosensitive hydrogels have the delicate hydrophobic/hydrophilic balances in their molecular structure.Its sol-to-gel or gel-to-sol transitions can be solely triggered by temperature,without employing the organic solvents,coupling agents,or any other external stimuli.The biodegradable and thermosensitive hydrogels are promising biomedical materials for drug carriers,delivery systems,and tissue engineering.In this paper,the recent researches on the biodegradable thermosensitive physically-crosslinked hydrogels were reviewed in detail and the correlations between copolymer chemophysical structure,gelation behavior,and hydrogel properties were highlighted.