包埋在温度及pH值敏感水凝胶中的阿司匹林的控制释放研究

STUDIES ON THE CONTROLLED RELEASE OF ASPIRIN IN THE TEMPERATURE & pH SENSITIVE HYDROGELS

直接将Ｎ－异丙基丙烯酰胺（ＮＩＰ）、丙烯酸和Ｎ，Ｎ′－甲叉双丙烯酰胺交联共聚合成了温度及ｐＨ值敏感水凝胶，包埋在此水凝胶中的抗结肠癌药物阿司匹林的释放随温度、介质ｐＨ值和药物制剂方式的变化而显著不同。在ｐＨ＝７．４的介质中３７℃时阿司匹林在水凝胶膜中的释放比２５℃时快，而在３７℃下ｐＨ＝７．４的介质中阿司匹林的释放比ｐＨ＝１．０快得多，后者在较长时间内仍释放一小部分，因此可将阿司匹林大部分定向到肠中释放。将膜剂改成粒剂后，可以获得较好的释放效果。

A temperature & pH sensitive hydrogel was synthesized by directly copolymerization of N isopropylacrylamide(NIP), acrylic acid and N,N′ methylenebisacrylamide. The release behavior of Aspirin(anti colonic cancer agent) entrapped in the hydrogels was of distinctly difference with the changes of temperature, pH value of release media and drug medicament. In the release medium of pH=7.4 the release of Aspirin in the Aspirin PNIP hydrogel films at T=37 ℃ was quicker than at T=25 ℃. while under the temperature 37 ℃, in the medium of pH=7.4 was much quicker than pH=1.0 where the release kept a little in a long time. Therefore Aspirin could mostly be guided to intestine to release. When the medicament was granules, the release was better.