Exudation of additives to the surface of medical devices: impact on biocompatibility in the case of polyurethane used in implantable catheters

Surface state is one of the most important parameters determining the biocompatibility of an implantable medical device, any change on the surface once in contact with body tissues can impact the biological response (cytotoxicity, inflammation, irritation, thrombosis, etc.). In the present study, we use (Pellethane^®) catheter-based polyurethane (PU), because of its many applications in the field of medical devices, to evaluate the impact of additives blooming on the biocompatibility. Four different antioxidants and two anti-ultraviolet stabilizers were included in this study. A comprehensive study was conducted to evaluate the consequences of cellular exposure to theses additives in the following three forms: in dissolved form and after surface blooming, in amorphous and in crystalized ones, and finally in the overall biocompatibility of the native PU. Surface roughness was analyzed with atomic force microscopy. Endothelial cells' viability was studied in contact with all the three physical forms. A preliminary hemocompatibility evaluation was performed through the measurement of whole blood hemolysis, as well as platelet adhesion in contact with the different PU samples. The study of the proinflammatory IL-α and TNF-α production by macrophages in contact with these films is also reported. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2954–2967, 2016.