乳酸甘胺酸共聚物 (PLGA) 由於具備生物相容性 (biocompatible) 與生物可劣解 (biodegradable) 等特性，因此能廣泛地應用在手術縫線、骨折癒合、組織工程及藥物釋放控制等方面。本研究中針對合成之乳酸甘胺酸共聚物的製備、物理性質與合成條件進行了一系列的探討，並將此合成製備之產物應用在多孔膜 (foam) 的製備與藥物的包覆上。

本研究中主要探討的主題有三方面：一為乳酸甘胺酸共聚物的製備及其性質之鑑定，合成之產物具有高純度且重量產率介於88-94% 之間，再者為在不同操作條件下以合成之共聚物製備多孔膜並歸納出最佳的製備條件，產物的形狀完整且表面孔洞均勻分散，其三則為包覆皮質固醇 (hydrocortisone) 之PLGA microspheres的製備，並對其製備程序、產物特性及藥物包覆的能力一一進行探討，包覆皮質固醇之PLGA microspheres最高可達50% 藥物含量。

PLGA can be widely used in sutures, fracture fixation, tissue engineering, and drug control/release because of its compatibility and biodegradation.
In this work, PLGA is successfully synthesized. PLGA of very high purity can be obtained with the yield of 88-94%. Its physical properties as well as the synthesis condition are discussed. The copolymer formed is applied to the preparation of porous foams and hydrocortisone-contained microspheres. The optimum condition for pre- paring porous foams is determined and an uniform foam of good shape is produced. For hydrocortisone-carried PLGA microspheres the preparation process, characteristic of the microspheres, and amount of drug being carried are all investigated. The maximum drug content of 50% can be achieved.

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