Hemocompatibility of polymeric materials for blood-contacting applications

Abstract

Hemocompatibility of a biomaterial plays a vital role in the overall success of the biomaterial in the body. Every implanted biomaterial tends to cause an immune response by the host tissue. The intensity of said response depends on many factors, including the properties of the material itself. In this study, we have assessed the hemocompatibility of expanded polytetrafluoroethylene (ePTFE), linear low-density polyethylene (LLDPE) and polyethylene terephthalate (PET); 3 potential materials for blood-contacting applications. The surface morphology was characterized using scanning electron microscopy (SEM), and surface wettability was characterized using contact angle goniometry. The cytotoxicity was investigated using lactate dehydrogenase (LDH) assay. The adsorption of key blood serum proteins was evaluated using micro-bicinchoninic acid (micro-BCA) assay. The results were visualized using SEM. Platelet adhesion and activation was investigated using live cell staining and SEM. Whole blood clotting kinetics were evaluated using a hemolysis assay and the results visualized using SEM. The results indicate that none of these materials are cytotoxic. Protein adsorption was highest on PET, and platelet adhesion was significantly higher on PET. However, the percentage of activated platelets and whole blood clotting kinetics was comparable on all materials. This work successfully creates a baseline against which the hemocompatibility of modified ePTFE, LLDPE and PET can be measured.