| 초록 |
The di-, tri- or multi-block copolymers composed of hydrophilic polyethylene glycol (PEG) and hydrophobic biodegradable polymer (lactide, glycolide, carprolactone) show the sol-gel transition with changing temperature. These block copolymers have been studied for the drug delivery system by many researchers. In this research, these thermo-sensitive block copolymer hydrogel were conjugated by the pH-sensitive moiety. The hydrophilicity and hydrophobicity of these block copolymers conjugated by pH-sensitive moiety is affected not only temperature change but also pH change. The pH-sensitive moiety used the sulfonamide derivatives, and the block copolymer conjugated by the sulfonamide derivatives was characterized by FT-IR and H1-NMR. The sulfonamide derivatives conjugated block copolymers showed the considerable difference of Critical Micelle Concentration with changing pH, and is significantly affected the sol-gel transition in high concentration solution with changing pH. That is to say, thermo and pH sensitive hydrogel was synthesized by conjugating the pH moiety in the thermo-sensitive block copolymer. |
