LONG TERM BIODEGRADATION OF ELASTOMERIC BIOMATERIALS

所提出的研究是针对理解的影响， 生理环境对高分子生物材料降解的影响。 将采用加速体内和体外方法研究 用于心血管应用的聚氨酯弹性体。 申请人的程序 将使用趋化作用开发加速体内生物降解测试 缩氨酸 肝组织中酶水平和炎性细胞的时间变化 渗出物将与观察到的性质变化相关。 模型 聚（α-氨基酸）弹性体将用于获得基本的 了解酶的降解机理。 应力增强是 提出了一种新的加速体外试验方法。 该方法也 与所选调查材料的许多最终用途应用相关。

The proposed research is directed toward understanding the effect of the physiological environment on the degradation of polymeric biomaterials. Accelerated in vivo and in vitro methods will be used to study biodegradation of polyurethane elastomers used in cardiovascular applications. Procedures for an accelerated in vivo biodegradation test will be developed using chemotactic peptides. Temporal variations of enzyme levels and inflammatory cells in the exudate will be correlated with observed property changes. A model poly(alpha-amino acid) elastomer will be used to gain a fundamental understanding of the enzyme degradation mechanism. Stress-enhancement is proposed as a new method of accelerated in vitro testing. This method is also relevant to many end use applications of the materials chosen for investigation.