pH 및 온도에 동시에 민감한 생분해성 하이드로젤의 합성 및 특성

pH- and thermo-sensitive hydrogels containing maleilated chitosan(MC) and N-isopropylacrylamide(NIPAAm) were prepared and characterized for their swelling behavior, biodegradability and drug release profiles. The hydrogels exhibited a typical pH-sensitivity due to the carboxylic acid groups of maleilated chitosan. The change of ratio of NIPAAm to MC in weight did not affect on either lower critical solution temperature(LCST) or EWC significantly. The pH sensitivity of the hydrogel, however, depended on the amounts of carboxylic acid groups of MC. MC was degradable up to 80% weight reduction in 2 hours. The in vitro drug relase profiles were established both in buffer solution pH 1.4 and pH 7.4. Only a negligible amount of indomethacin was released at pH 1.4 in 6 hours, while at pH 7.4 more than 90% of the total drug in the hydrogel was gradually released over ca. 5 hours.

pH 및 온도에 동시에 민감한 하이드로젤을 maleilated chitosan과 N-isopropylacrylamide를 이용하여 합성하였으며, 합성된 하이드로젤은 NIPAAm의 양에 관계없이 비슷한 pH 민감성을 나타내었으며 부피상 전이온도는 모두 NIPAAm의 LCST의 온도인 $32^{\circ}C$부근에서 나타났다. 반면에 MC의 양을 소량 첨가한 하이드로젤은 그만큼 pH의 민감성이 떨어졌다. lysozyme에 의한 MC의 생분해는 2시간이내에 80%가 분해되었다. 또한 indomethacin을 이용한 약물방출 실험에서는 제조된 하이드젤이 방출제어형 약물전달체로서 좋은 결과를 보인 제형으로 관찰되었다.