Application of Diamond-Like-Carbon Coating to a Coronary Artery Drug-Eluting Stent

抄録

The surfaces of medical materials are coated with polymer molecules or drugs in order to functionalize the surfaces in such ways as imparting biocompatibility. But in the case of inorganic materials there is the problem that polymers will have poor adhesiveness and be liable to peel. A coronary artery stent holds the vessel lumen patent by being expanded to the plastic deformation region, and if the material surfaces are coated with DLC, the coating must follow the plastic deformation of the base material. Accordingly we created a thickness-wise concentration gradient in the Si content that is added to the DLC, and discovered that thereby a DLC nanocoating is produced that does not crack under the plastic deformation required in a stent, and that has superior adhesion. In this way we succeeded in improving adhesion of the drug coating when used in combination with thin film material obtained via application of plasma surface treatment techniques, and in producing a practical stent that exhibits high biocompatibility even after slow release of the antithrombotic agent into the body is complete.