医用聚乳酸体内降解机理及应用研究进展

Research Progresses on Degradation Mechanism in Vivo and Medical Applications of Polylactic Acid.

聚乳酸 (PLA)是一种具有良好生物相容性的聚酯类可生物降解材料 ,近年来在医学领域的应用日益受到重视。PLA的应用与其降解特性有着直接的关系。PLA的水解主要包括吸水、酯键的断裂、可溶性齐聚物的扩散和碎片的溶解等 4个过程。本文重点综述了以下内容 :PLA的酶解和水解两种降解机理研究 ,尤其对PLA由于内部存在自加速效应而导致内部降解比表面快并形成中空的壳层结构这一新的降解理论作了较详细的叙述 ;影响PLA降解的因素很多 ,本文主要讨论了材料组成、结晶形态、合成方式和几何形状对PLA降解的影响 ;PLA植入体内后的生理学反应 ;

Polylactic acid (PLA), a kind of aliphatic polyester, is a bio de gradable polymer with outstanding biocompatibility. The degradation of PLA is a complex process involving four main phenomena, namely water absorption, ester cl eavage, diffusion of soluble oligomers, and solubilization of fragments. This pa per emphasizes on the following aspects: 1)present understanding of the hydrolyt ic degradation and enzymatic degradation of PLA and autocatalystic degradation mechanism in the bulk PLA;2)main factors influencing PLA degradation;3)biologica l results;4)the development in application of PLA