A biodegradable, injectable, gel system based on MPEG-b-(PCL-ran-PLLA) diblock copolymers with an adjustable therapeutic window

作者：Kang Yun Mi; Lee Sang Hyo; Lee Ju Young; Son Jin Soo; Kim Byung Soo; Lee Bong; Chun Heung Jae; Min Byoung Hyun; Kim Jae Ho; Kim Moon Suk^*

来源：Biomaterials, 2010, 31(9): 2453-2460.

DOI：10.1016/j.biomaterials.2009.11.115

• In situ-forming gel
• Phase transition
• MPEG-b-(PCL-ran-PLLA) diblock copolymer
• Degradation

In situ-forming gel systems have drawn increasing attention for their potential use in a variety of biomedical applications Here. we examined an In situ-forming gel system comprised of MPEG-b-PCL- and MPEG-b-(PCL-ran-PLLA) diblock copolymers with different PLLA contents (0-10 mol%) in the PCL segment The crystalline region of the PCL-ran-PLLA segment decreased with Increasing PLLA content The MPEG-b-(PCL-ran-PLLA) diblock copolymer solutions were liquid at room temperature and only MPEG-b-(PCL-ran-PLLA) diblock copolymer solutions with a PLLA content 55 mol% in the PCL segment showed a sol-to-gel transition as the temperature was Increased The viscosity change associated With sol-to-gel phase transition depended on the PLLA content in the PCL segment A MPEG-b-PCL diblock copolymer solution incubated in vitro showed Increasing viscosity without degradation, whereas the viscosity of MPEG-b-(PCL-ran-PLLA) diblock copolymer solutions Continuously and sharply decreased with increasing PLLA content in the PCL segment As the amount of PLLA increased. the size of in vivo formed MPEG-b-(PCL-ran-PLLA) gels after initial injection tended to gradually decrease because of hydrolytic degradation of the PLLA in the PCL-ran-PLLA segment An immunohistochemical examination showed that in vivo MPEG-b-(PCL-ran-PLLA) diblock copolymer gels provoked only a modest inflammatory response. Collectively, our results show that the MPEG-b-(PCL-ran-PLLA) diblock copolymer gel described he

• 出版日期2010-3