| 초록 |
Stimuli-sensitive hydrogels have attracted considerable attention as intelligent materials in the biochemical and biomedical fields because these materials have the abilities to response environmental changes and induce structural changes. Especially, injectable pH and temperature sensitive hydrogels may be easy to inject into body. The synthesis of temperature sensitive block copolymer was performed through a ring-opening polymerization of D,L-lactide, ε-caprolactone. PEG was used as a initiator. The oligo-sulfamethaizne(OSM) was coupled with the end of the block copolymer to show the pH sensitivity of temperature sensitive block copolymer. To maintain stable gel in the condition of body as 37 ℃, pH 7.4 for a long-term, hydrophilic(PEG)/hydorphobic (PCLA) ratio of OSM-PCLA-PEG-PCLA-OSM block copolymer hydrogel was controlled and molecular weight of PEG(1500, 1620, 1750, 2000) of that block copolymer was changed. Moreover, molecular weight of OSM(pH sensitive moiety) was controlled. Human osteoblast stem cells had adhered and multiplied on pH and temperature sensitive hydrogels in vitro. Cells were mixed with pH and temperature sensitive hydrogels and subcutaneously injected into the backs of mice in vivo. They were investigated by optocal microscope after 1week, 2weeks, 4weeks and 6weeks, respectively. |
