Fibrin Formation and Morphologies at Biomaterial Interfaces

Cardiovascular diseases affect the heart and blood vessels with potentially fatal consequences, to the extent where they have consistently comprised the leading cause of death worldwide. Many treatments or preventions of these diseases are
based on implantation of medical devices, but the synthetic nature of such materials frequently elicits adverse reactions in the patient. The principal complication is blood clotting on the surface biomaterial of the medical device, as the protein fibrin forms a network of fibers that eventually blocks blood flow. Despite this ubiquitous challenge when foreign substances enter the bloodstream, medical devices are still designed with chemically diverse biomaterials that are clotted with fibrin by a variety of poorly understood mechanisms. In this research project, the formation and adsorption of fibrin was investigated in the context of how biomaterials induce blood clots. Fibrin was formed both under static and dynamic conditions, under exposure to materials used in or relevant for medical devices. Multiple distinct morphologies were identified and correlated with different mechanisms of fibrin formation, including previously unknown fractal branched structures. Surface-dependent studies compared how different materials affect fibrin clotting, and indicated which substrates would be comparably preferable as biomaterials. These new insights can be used to optimize medical device design, based on identification and characterization of materials that limit pathological blood clotting and other adverse reactions in implant patients.