Coating stability for stents

Abstract The stability of a stent coating is critical and needs to be satisfied during processing, shelf life, and the use of the implant. This chapter will focus on the stability from a material point of view. Several stability tests are being discussed. Static and dynamic tests involve immersion in aqueous medium and the shaking of the samples during the contact with fluids in the latter test. The coating adhesion to the substrate is usually tested via simple peel tests or dynamic test involving stent expansion. In the specific case of drug-eluting stents, the accomplishment of their stability could be very different due to the purpose of these kinds of stents. Indeed, more than stability tests, the rate of delivery of the drugs is examined. Finally, the growth of endothelial cells on the surface of the coating and the further stability of this cell layer are investigated. Studying the stability of the coatings remains substantial to ensure the holding of the device and its success after implantation.