PNIPAM改性纤维素球调控布洛芬释放

Preparation of PNIPAM-Cellulose Based Microspheres for Controlled Ibuprofen Release

简要介绍了聚（N-异丙基丙烯酰胺）（PNIPAM）改性的纤维素球对药物的可控释放,该产物具有温度敏感和p H值敏感的特性。运用可逆加成-断裂链转移聚合反应,将PNIPAM链接到纤维素微球上,分别采用傅里叶变换红外光谱,扫描电子显微镜,透射电子显微镜,X射线光子能谱分析和热重分析等方法,证实了PNIPAM成功地链接到纤维素微球上。PNIPAM-纤维素微球的直径为1.2~2μm,具有良好的生物相容性,有利于用作药物载体控制药物释放。布洛芬被选择作为模型药物分子以测试PNIPAM-纤维素微球的药物负载和释放性能。结果表明,PNIPAM-纤维素球的布洛芬释放速度在25℃比在38℃快,在p H值7.4快于p H值4.0。由于PNIPAM-纤维素微球的热敏性和p H值敏感性,使得它可以广泛应用于可控的药物释放。

Thermosensitive and pH-sensitive poly（ N-isopropylacrylamide）（ PNIPAM）-cellulose based microspheres were synthesized and utilized as carriers to load and release drugs in controlled modes. These microspheres were prepared using cellulose microspheres as templates to graft PNIPAM via reversible addition fragmentation chain transfer polymerization. The grafting of PNIPAM to cellulose microspheres was confirmed by Fourier-transform infrared（ FTIR） spectroscopy,scanning electron microscopy （ SEM ）, transmission electron microscopy （ TEM ）, X - ray photon spectroscopy（ XPS ） analysis and thermogravimetric analysis （ TGA ）. The PNIPAM - cellulose microspheres with a diameter of 1. 2 ~2 μm were biocompatible and favorable to be utilized as drug carriers for controlling drug release. Ibuprofen was chosen as a model drug to test the drug loading and releasing properties of the PNIPAM - cellulose microspheres. It was found that the ibuprofen released from the microspheres at 25℃ was more rapidly than that at 38℃, and it released more rapidly at pH 7. 4 than that at pH 4. 0. Providing the favorable thermosensitivity and pH-sensitivity, the PNIPAM-cellulose microspheres are expected to be widely used as drug carriers for controlled drug release.