HEMOCOMPATIBLE MATERIALS

The complexity of the interactions between materials and blood makes the development of hemocompatible surfaces very difficult. Biomaterials research is focused on developing materials that have fewer risks and greater benefits. Stents that ‘‘actively’’ prevent restenosis are a great example of how surface modification of metals can result in a dramatic clinical effect. Inert materials are protein and platelet resistant, but they do not prevent thromboembolic phenomena in vivo. On the other hand, incorporating anticoagulants in to surfaces reduces thrombin production, but this may not be sufficient to prevent platelet adhesion and activation. Thus, which approach will ultimately be successful is impossible to predict. Perhaps, the failure to produce an ideal blood-compatible surface merely reflects our limited understanding of the complex blood-materials interaction. Progresses in design hemocompatible materials will be then determined by a deeper understanding of both the surface properties of materials and the interfacial phenomena originating at the blood–material interface.