Oral presentations O1.1 Contact of blood and endithelial cells with surface-modified metallic biomaterials

Significant progress made in materials science, mainly in the technology of surface, allows for intentional modifications of metallic surfaces. Thin layers of modified surfaces separate metallic substrates from environment and prevent them from corrosion. However, a real opportunity to control the interaction of surface with surrounding tissues and body fluids, with respect to the anticipated application, seems to be even more important. This way, one can produce a metallic implant with strictly defined properties for specific applications. A long term contact of blood components or endothelial cells with biomaterials can be crucial for a variety of biological processes. Response of blood platelets and endothelial cells to this contact may be a highly important factor in the case of such processes as inflammation, blood coagulation, angiogenesis, osteointegration and many others, in which endothelial cells and blood platelets play a key role. In the case of reconstructive arterial or cardiac surgery the cells are in direct contact with the implant surface. Our practical experience with surface modifications concerns medical steel 316L and titanium alloy Ti6Al4V. Both substrates were coated with thin layers of carbon (DLC or NCD films) by RF PCVD method elaborated by Prof. Mitura team (1). The titanium alloy was also subjected to glow discharge procedure. This process was carried out by Prof. Wierzchon group (2), and resulted in the production of thin layers of TiN or TiCN on titanium alloy surface. Both modifications prevented the base materials from corrosion and made alloy surface more durable. We have found that carbon layers generally made metallic surface more biocompatible and more resistant to biofilm production. Introducing titanium nitride or titanium carbonitride layers allows for the modulation of thrombogenity degree of the surface. Our investigations employed fluorescence and electron microscopy techniques, SPR-biosensor technology, 2D-electrophoresis and flow cytofluorymetry.