In this project, MicroFab will develop an ink-jet based system for coating of cardiovascular stents with polymer-drug solutions. Previous clinical trials have proven drug coated stents to be superior to the uncoated stents by significantly reducing the restenosis risk. Current manufacturing methods are not easily controlled, are wasteful from a material standpoint, could result in non-uniform coating or could deposit material in undesired areas. Our ink-jet based stent coating system will be a flexible manufacturing tool that eliminates the drawbacks of current manufacturing methods. The ink-jet process is data controlled so it allows easily changes between different stent configurations. It generates little waste and reduces the cost of materials. By its very precise nature, ink-jetting produces a very uniform coating with no overcoating, currently a problem resulting in a large number of rejects. The proposed system will especially benefit R&D activities for the next generation of stents, as it allows the fabrication of complex coatings using multiple drugs, polymers or solution concentrations to adjust the drug release. In Phase I MicroFab will build the ink-jet coating system and develop the printhead that will dispense the polymer-drug solutions. The microdispenser operational parameters required to jet the solutions will be identified. Cardiovascular stents will be coated by ink-jet technology and evaluated in terms of loaded drug amount and loading efficiency and coating thickness and uniformity. We will also evaluate the stent to stent coating consistency.
