| 초록 |
The present study reports on a thermogelling poly(ethylene glycol)-poly(L-alanine-co-L-phenyl alanine) grafted chitosan (CS-g-(PAF-PEG)) system, focusing on phase diagram, transition mechanism, and in-vivo gel duration. The sol-to-gel transition temperature decreased from 27 oC to 11 oC as the concentration increased from 4.0 wt.% to 9.0 wt.%. The polymer formed micelles ranging in a size from 10 – 50 nm at 10 oC, and formed large aggregates hundreds to thousands nm in size as the temperature increased from 10 oC to 35 oC, suggesting that an extensive molecular aggregation might be involved in the sol-to-gel transition. A gel was formed in situ after injecting the CS-g-(PAF-PEG) aqueous solution into subcutaneous layer of rats. About 70% of the gel was eliminated in 1 week, and the remaining gel was completely cleared from the implant site in 14 days. The results indicate the potential of CS-g-(PAF-PEG) as a promising short-term carrier biomaterial for pharmaceutical agents. |
