摘要
背景:利用缓释系统释放生长因子,是目前生物活性因子应用研究的方向之一。目的:应用离子交联沉淀法制备壳聚糖-转化生长因子β1缓释微球,观察其体外缓释性能以及细胞相容性。设计、时间及地点:观察性实验,于2006-10/2007-09在华中科技大学同济医学院附属协和医院中心实验室完成。材料:壳聚糖,脱乙酰度90%,由清华大学化学工程系提供;转化生长因子β1,由晶美公司提供;大鼠由华中科技大学同济医学院实验动物中心提供。方法:①离子交联沉淀法制备壳聚糖微球,并包裹转化生长因子β1,制备可体外缓释转化生长因子β1的壳聚糖-转化生长因子β1缓释微球。②选择传代二三次、生长良好的大鼠胸降主动脉中层肌成纤维细胞,调节细胞密度至1×108L-1,分别加入不同浓度(4,2,1g/L)壳聚糖微球浸提液,不含浸提液的培养基作为对照培养。主要观察指标:扫描电镜、激光粒度分析仪、Elisa法观察微球表面形态,测定药物载药率、包封率、体外缓释效率等指标;四甲基偶氮唑盐法观察细胞增殖情况,评估壳聚糖微球体外细胞相容性。结果:所得微球球形良好,表面光滑,粒径分布集中,平均粒径272nm。壳聚糖微球有较高的药物包封率,达80.60%。体外释放试验提示,转化生长因子β1初期存在突释现象,前24h释放达27%,其后可从壳聚糖微球中稳定释放,7d累计释放达41%。四甲基偶氮唑盐法提示该壳聚糖微球对细胞体外生长无不良影响,相容性好。结论:离子交联沉淀法制备壳聚糖缓释微球方法简单易行,所得壳聚糖-转化生长因子β1微球具有良好的缓释效能及细胞相容性。
BACKGROUND： Releasing growth factor through controlled release system is one of the study directions of bioactive factor application.
OBJECTIVE： To prepare transforming growth factor β1 （TGF-β1） loaded chitosan microspheres with ionically cross-linking precipitant method, and to study the properties of controlled release of TGF-β1 and biocompatibility in vitro.
DESIGN, TIME AND SETTING： An observational trial was performed in the central labotatory, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology （Wuhan, Hubei, China） from October 2006 to September 2007.
MATERIALS： Chitosan, 90% deacetylation degree, was offered by Tsinghua University Chemical Engineering Department; TGF-β1 was offered by Jingmei Biotech Co., Ltd.; Rats were offered by the Experimental Animal Center of Tongji Medical College, Huazhong University of Science and Technology.
METHODS： Chitosan microspheres were prepared with ionically cross-linking precipitant method, and TGF-β1 was then packaged in the microspheres. After passage culture, myofibroblasts in descending thoracic aorta of rats at the adjusted concentration of 1× 10^8/L were added with chitosam microsphere leaching liquor （4, 2, 1 g/L）, while the medium without leaching liquor was taken as controls.
MAIN OUTCOME MEASURES： The features such as the size distribution, drug content, drug encapsulating and in vitro release were studied with scanning electron microscope, laser grainsize analyzer and ELISA method. MTT test was performed to observe cell proliferation and evaluate the biocompatibility in vitro.
RESULTS： The microspheres were spherical and smooth. The mean diameters of the spheres were 272 nm, and the high encapsulation efficiency was obtained, about 80.6%. The sudden release of TGF-β1 was observed in the initial period in test of release in vitro, and then TGF-β1 could be constantly released from the chitosan microspheres （27% in 24 hours and up to 41% in 7 days）. MTT showed that the chitosan microspheres did not damage the cell growth in vitro, indicating good compatibility.
CONCLUSION： The method to prepare chitosan microspheres with ionically cross-linking precipitant is convenient and feasible, and TGF-β1 possesses good delayed release and compatibility.
出处
《中国组织工程研究与临床康复》
CAS
CSCD
北大核心
2008年第32期6243-6246,共4页
Journal of Clinical Rehabilitative Tissue Engineering Research
基金
国家自然科学基金资助项目(C30371414,C30571839,C30600608)~~
