| 초록 |
The development of new biodegradable polymers for injectable drug delivery systems has attracted so much attention over the past few years. Among them, the inventions of biodegradable poly(ethylene oxide-block-L-lactic acid (PEO-PLLA) and poly(ethylene oxide-block-lactic acid-block-ethylene oxide) (PEO-PLA-PEO) by Jeong et al. showed gel to sol transition behavior in aqueous solution over a specific concentration with increasing temperature. These materials displayed sol to gel and gel to sol transition behaviors in aqueous solution and the gel state was maintained for more than one month in the body of a rat. A new series of thermosensitive biodegradable hydrogels based on PLGA-PEG block copolymers were synthesized by "grafting through" and "grafting from" methods in our laboratory. Physically crosslinked hydrogels of amphiphilic p((PEG-PLGA)MA) block copolymers were characterized by 1H NMR, GPC, FT-IR etc. Sol-gel transition behavior was also investigated by tube-tilitng method. |
