Evaluation and characterization of the waterborne biodegradable polyurethane films for prevention of the tendon postoperative adhesion

Tendon adhesion has been a serious problem and it affects the tendon gliding and joint motion. Although recent studies have yielded promising results in developing anti-adhesion materials, there are still many problems, especially in clinical applications. Polycaprolactone (PCL)-based Polyurethane (PU) has good mechanical properties and biocompatibility, and it has a potential in anti-adhesion applications. In this study, a series of PUs with different ratios of ionic groups were synthesized. The PU films were cast and characterized for physico-chemical properties and biocompatibility. The most appropriate one was selected for animal studies and implanted to the tendons of the rabbits. All PU films were non-cytotoxic to cells and had mechanical properties suitable for anti-adhesion applications of the tendon surgery. Meanwhile, PU films demonstrated a lower peeling energy than the PCL film by the gelatin test, indicating that gelatin or extracellular matrix may not be easily deposited on the PUs. The rabbit implantation showed that PU had better anti-adhesion effect than PCL films and the untreated control, and demonstrated no significant difference in the anti-adhesion performance from the commercial product Seprafilm.