Biodegradation of poly (etherurethanes)

Abstract

Polyurethanes have found widespread applications in biomedical engineering, such as implant coat material, catheter coat material and drug delivery among others, for their biocompatibility and biodegradability. These polyurethanes have been found to degrade with time when implanted. For medical purpose, studies on degradation of polyurethanes have attracted great interest. Hydrolytic, oxidative and enzymatic degradation of polyurethane membrane was investigated for one week. The in vitro degradation medium used was such that mimic in vivo conditions. Hydrolytic degradation was performed in simulated body fluid at 37C. Oxidative degradation was performed with 0.1M cobalt chloride in hydrogen peroxide at 37C. Enzymatic degradation was performed using esterase enzyme (40Units/ml) in phosphate buffer solution (pH 7.4) at 37.The degradation was characterized by x ray diffraction. Results of polyurethane degradation with three types of degrading medium were compared.