Enzymatic degradation of poly(ether urethane) and poly(carbonate urethane) by cholesterol esterase

详细信息    查看全文

• 作者：Elizabeth M. Christenson ; Sachin Patel ; James M. Anderson and Anne Hiltner
• 关键词：Poly(carbonate urethane) ; Poly(ether urethane) ; Biodegradation ; Cholesterol esterase ; In vivo ; In vitro
• 刊名：Biomaterials
• 出版年：2006
• 出版时间：July 2006
• 年：2006
• 卷：27
• 期：21
• 页码：3920-3926
• 全文大小：481 K

文摘

This study examined the effect of cholesterol esterase (CE) on the degradation of commercial poly(ether urethane) (PEU) and poly(carbonate urethane) (PCU). Unstrained PEU and PCU films were incubated in 400 U/mL CE solution or a buffer control for 36 days. The study used a concentration of cholesterol esterase that was considerably higher than the estimated physiological level in order to accelerate degradation. However, characterization of treated polyurethane films with SEM, attenuated total reflectance Fourier transform infrared (ATR-FTIR) and GPC analysis revealed only a small loss in surface soft segment content. Comparison with implanted PEU and PCU films led to the conclusion that any effect of enzymatic hydrolysis was confined to the immediate surface, and the magnitude of the effect was too small to contribute significantly to in vivo degradation. The study confirmed that oxidation, rather than enzymatic hydrolysis, is the primary mechanism responsible for the observed biodegradation of PEU and PCU. The oxidative H₂O₂/CoCl₂ treatment continues to accurately predict the long-term biostability of polyurethanes.