【摘要】 先使用N-异丙基丙烯酰胺和N-羟甲基丙烯酰胺合成共聚物,以其为成纤聚合物用静电纺丝工艺制备纳米纤维,然后进行高速搅拌将纳米纤维切短并分散在叔丁醇中,最后进行冷冻干燥和热处理将切短的纳米纤维组装成具有多级多孔结构的纳米纤维水凝胶。这种纳米纤维水凝胶在水中具有良好的稳定性、压缩回弹性和显著的温度响应性。当水介质温度在20～55℃交替变化时它具有超快的温度响应性,达到消溶胀平衡的时间为34 s,达到溶胀平衡的时间为45 s。体外药物释放实验结果表明,当pH值为7.4的磷酸盐缓冲溶液的温度在15～47℃交替变化时,其中浸入的载模型药物葡聚糖的温度响应性纳米纤维水凝胶以"开/关"模式可控释放药物。更多还原

【Abstract】 The nanofibers were firstly prepared by static electrospinning process using the fiberforming copolymer synthesized from N-isopropylacrylamide and N-methylol acrylamide, and then they were shortened and dispersed in tert-butanol by high-speed stirring. Finally, the shortened nanofibers were assembled into nanofibrous hydrogel with hierarchical porous structure by the processes of freeze drying and followed heat treatment. The resultant nanofibrous hydrogel in aqueous medium holds excellent stability, compression resilience and remarkable temperature-responsiveness. When the temperature of an aqueous medium changed alternately between 20℃ and 55℃, in which the nanofibrous hydrogel reached its swelling-and deswelling-equilibrium state within 34 s and 45 s respectively,exhibiting ultra-fast temperature responsiveness. In vitro drug release experiment results show that when the temperature of the phosphate buffered solution of pH7.4 is altered alternately between 15 oC and 47 oC the immersed dextran(model drug) loaded nanofibrous hydrogel can controllably release the drug by ’ on/off ’ mode.更多还原