| 초록 |
In the search for an enzymatically degradable thermogelling system, we are reporting poly(alanine-co-leucine)-poloxamer-poly(alanine-co-leucine) (PAL-PLX-PAL) aqueous solution. As the temperature increase, the polymer aqueous solution underwent sol-to-gel transition at 20~40oC in a polymer concentration range of 3.0 wt.%~ 10.0 wt.%. The amphiphilic polymer form micelles in water, where the hydrophobic PALs form a core and gydrophilic PLXs form a shell of the micelle. a-helical secondary structure of PAL was quite stable in 20~50oC, whereas the PLX showed significant decrease in molecular motion during the sol-to-gel transition. The polymer was degraded by proteolytic enzymes such as matrix metalloproteinase and elastase, whereas it was quite stable against cathepsin B and cathepsin C, and chymotrypsin or in PBS. The in-situ formed gel in the sucutaneous layer of rats showed histocompatibility and a duration of about 45days. |
