复合材料气管内可降解支架的降解性能  

Degradable properties of biodegradable composite stents in the trachea

作　　者：马永富[1] 刘阳[1] 郭俊唐[1] 张涛[1] 梁朝阳[1] 

机构地区：[1]解放军总医院胸外科,北京市100853

出　　处：《中国组织工程研究》2013年第29期5371-5378,共8页Chinese Journal of Tissue Engineering Research

基　　金：解放军总医院苗圃基金(06MP21)~~

摘　　要：背景:经过对目前国内外可降解材料支架研究的充分调研,以及在镍钛记忆合金支架设计、制作、实验和临床应用的经验基础上,提出一种新型自膨式左旋聚乳酸可降解覆膜气管内支架的研究。目的:自行制作左旋聚乳酸复合羟基磷灰石生物可降解材料气管内支架,测试其机械力学、生物相容性及降解性能。方法:利用计算机辅助设计支架模型,应用相对分子质量150000的左旋聚乳酸和羟基磷灰石按一定比例混合后研制直径分别为20,21,22,23,24,25,26mm的可降解气管内支架,采用万能实验机检测其力学性能。将研制的可降解气管内支架以合适的尺寸置入杂种犬气管狭窄模型,置入后4,8,12,16周观察支架黏均分子质量及质量变化,同时检测可降解气管内支架体外降解黏均分子质量及质量的变化。结果与结论:复合材料可降解气管内支架的平均径向支撑力为7.8kPa,支架表面覆盖率小于20%,支架扩张率≥4%,支架纵向缩短率≤9%,已达到气管内可降解支架的力学要求。支架置入后4-16周组织病理学观察未见明显炎症反应。支架体内降解解组不同时间点的黏均分质量下降程度及质量损失率高于体外降解组(P均<0.05)。表明左旋聚乳酸/羟基磷灰石复合材料支架具有良好力学性能、生物相容性及可降解性。BACKGROUND：Through a ful investigation of biodegradable scaffolds, we propose a new self-expanding degradable poly-L-lactide coated endotracheal stent based on the design, production, experimental and clinical applications of nickel titanium memory alloy stent. OBJECTIVE：To design a kind of biodegradable endotracheal stent with poly-L-lactide and hydroxyapatite, and to test its mechanical properties, biocompatibility and biodegradation capacity. METHODS：With the technology of computer aided design, the stents were prepared with poly-L-lactide （Mr RESULTS AND CONCLUSION：The average radial supporting force of the tracheal stent was 7.8 kPa, the percentage of stent surface coverage was less than 20%, the stent expansion rate was≥4%, and the stent longitudinal shortening rate was≤9%, which reached the mechanical requirements for degradable endotracheal stents. After 4-16 weeks, there was no significant inflammatory response. The decline in molecular weight changes and weight loss ratio was higher for in vivo degradation than in vitro degradation at different time （P〈0.05）. These findings indicate that poly-L-lactide/hydroxyapatite composite stents have good mechanical properties, biocompatibility and biodegradability. 150 000） and hydroxyapatite materials, 20 mm to 26 mm in diameter. The mechanical properties were tested using a universal testing machine. These poly-L-lactide/hydroxyapatite stents were implanted into dog models of tracheal stenosis at an appropriate size. The histopathological changes of the tracheas were observed, and biodegradation property was studied via molecular weight changes and weight loss ratio after 4, 8, 12, 16 weeks.

关 键 词：生物材料 组织工程复合支架材料 组织工程骨材料 气管 可降解 支架 左旋聚乳酸 羟基磷灰石 生物相容性 其他基金 

分 类 号：R318[医药卫生—生物医学工程]