Fibrin Adsorption on Cardiovascular Biomaterials and Medical Devices

Medical devices that are insertedin blood vessels always riskeliciting thrombosis, and the surface properties of such devices arethus of major importance. The initiating step for surface-inducedpathological coagulation has been associated with adsorption of fibrinogenprotein on biomaterial surfaces and subsequent polymerization intoan insoluble fibrin clot. This issue gives rise to an inherent challengein biomaterial design as varied surface materials must fulfill specializedroles while also minimizing thrombotic complications from spontaneousfibrin(ogen) recruitment. We have aimed to characterize the thrombogenicproperties of state-of-the-art cardiovascular biomaterials and medicaldevices by quantifying the relative surface-dependent adsorption andformation of fibrin followed by analysis of the resulting morphologies.We identified stainless steel and amorphous fluoropolymer as comparativelypreferable biomaterials based on their low fibrin(ogen) recruitment,in comparison to other metallic and polymeric biomaterials, respectively.In addition, we observed a morphological trend that fibrin forms fiberstructures on metallic surfaces and fractal branched structures onpolymeric surfaces. Finally, we used vascular guidewires as clottingsubstrates and found that fibrin adsorption depends on parts of theguidewire that are exposed, and we correlated the morphologies onuncoated guidewires with those formed on raw stainless-steel biomaterials.