摘要
以N-异丙基丙烯酰胺(NIPAAm)系共聚凝胶为研究对象,通过引入亲水单体丙烯酰胺(AAm)和疏水单体甲基丙烯酸丁酯(BMA)制备PNIPAAm,P(NIPAAm-co-AAm)和P(NIPAAm-co-BMA)3种具有不同亲水性的共聚凝胶,研究NIPAAm系共聚凝胶对亲水性不同的2种模型药物的载药与释药行为。研究结果表明:NIPAAm系共聚凝胶呈现热缩温敏特性,在相转变温度(LCST)以下,随着凝胶亲水性的增强,凝胶的LCST升高,平衡溶胀比和初始溶胀速率增大;亲水性药物水杨酸钠的载药率提高,而增强凝胶的疏水性则有利于提高水杨酸的载药率;水杨酸和水杨酸钠的初始释药速率均增大,水杨酸钠初始释药速率明显大于水杨酸初始释药速率。对于亲水性相对较弱的水杨酸,高温下的平衡释药率明显小于低温下的平衡释药率,而对亲水性较强的水杨酸钠,PNIPAm共聚载药凝胶高温和低温平衡释药率相差不大;在温度低于LCST时,3种凝胶对于水杨酸的平衡释药率相差很大,而对于水杨酸钠的平衡释药率均为100%。
A series of N-isopropylacrylamide （NIPAAm） copolymer gels with different hydrophilicity was prepared from NIPAAm, hydrophilic acrylamide （AAm） and hydrophobic butyl methacrylate （BMA）. The swelling and thermo-responsive properties of NIPAAm, P（NIPAAm-co-BMA） and P（NIPAAm-co-AAm） copolymer hydrogels were investigated. Their drug loading and releasing behaviors for two kinds of model drug with different hydrophilic were studied. The results show that the copolymer gels present negative thermo-sensitivities. The lower critical solution temperature （LCST）, equilibrium swelling degree and the initial swelling rate increase as the hydrophilicity of gels enhances when the temperature is below the LCST. With enhancing gel hydrophilicity the loading ratio for sodium salicylate increases, while for salicylic acid, just the reverse. The initial drug releasing rates of sodium salicylate and salicylic acid heighten with increasing gel hydrophilicity. The initial drug releasing rates of sodium salicylate is significantly higher than that of salicylic acid. For salicylic acid with less hydrophilicity, the equilibrium releasing rate at high temperature is higher than that at low temperature, while for sodium salicylate with more hydrophilicity, the equilibrium releasing rate at high temperature is almost the same as that at low temperature. Equilibrium releasing rates of three gels are significantly different for salicylic acid when the temperature is blow LCST, while equilibrium releasing rates of three gels are 100% for sodium salicylate.
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2007年第5期906-911,共6页
Journal of Central South University:Science and Technology
关键词
水凝胶
亲水性
疏水性
溶胀
控制释放
hydrogel
hydrophilic
hydrophobic
swelling
controlled release
