聚乳酸生物可吸收支架在静态和动态系统中降解行为的研究  

Degradation Behaviors for PLLA Bioresorbable Scaffolds in Both Static and Dynamic Degradation Systems

作　　者：罗七一[1,2] 黄楚波 王帅 孟娟 常兆华[1,2] 朱钰方[1] 华泽钊[1] 

机构地区：[1]上海理工大学医疗器械与食品学院,上海200093 [2]上海微创医疗器械(集团)有限公司,上海201203

出　　处：《中国生物医学工程学报》2014年第4期447-454,共8页Chinese Journal of Biomedical Engineering

基　　金：2013年上海市科技支撑计划项目(13441902700);2011年上海市科技创新行动计划-研发基地与研发平台建设领域(11DZ2280100);2011年上海市浦江人才计划(11PJ1432500)

摘　　要：本研究通过建立体外静态和动态降解系统,探讨聚乳酸(PLLA)生物可吸收支架在体外动态和静态降解系统中的降解行为及之间的关系。研究采用凝胶渗透色谱(GPC)、调制式示差扫描量热仪(MDSC)等手段表征支架材料相对分子质量及热力学性能,采用扫描式电子显微镜(SEM)、电子天平、非接触式显微镜测量系统及径向力测试仪分别测量支架的表面形貌、质量、支架外径及支撑力。结果显示,在静态和动态降解系统中,PLLA支架表观随降解时间增加没有明显区别;材料相对分子质量在降解6个月后分别下降至61.7%和68.5%,但下降趋势相似;在动态降解系统中支架材料相对分子质量的多分散性指数(PDI)要大于静态降解系统中的;支架材料在降解过程中各阶段的热力学性能无明显差异;支架的外径变化趋势相似;径向支撑力在两个降解系统中的变化量均不大。支架材料在静、动态降解系统中的降解行为较为相似,在血管重建期内的6个月内可用静态降解系统代替昂贵、复杂的动态降解系统来研究PLLA生物可吸收支架产品的降解行为。In this study, static and dynamic degradation systems were set up to understand the degradation behaviors of PLLA （poly-l-lactic acid） bioresorbable scaffolds （BRS） between the two systems. GPC and MDSC methods were employed to characterize molecular weight and thermodynamic properties of the material. Surface morphology, mass loss, diameter and radial strength of BRS were evaluated by scanning electron microscope （SEM）, electronic balance, non-contact measurement system and radial force tester, respectively. The results showed that molecular weight （Mw） of the BRS kept dropping in static and dynamic systems with increasing degradation time, and it was reduced to 61.7% and 68.5% of their original Mw（0） respectively after six months, but there were no significant differences between the two systems. Polydispersity index （PDI） of PLLA in the dynamic system was larger than that in the static system, suggesting inhomogeneous degradation in the dynamic degradation system. Thermodynamic properties, the surface morphology and the changes of outside diameters （OD） as well as the radial strengths were quite similar in the two systems. Based on these results, the complex dynamic degradation system could be replaced by the static degradation system for studying degradation behaviors of PLLA BRS products within 6 months.

关 键 词：生物可吸收支架 静态降解行为 动态降解行为 

分 类 号：R318[医药卫生—生物医学工程]