Patent ID: 8915957
Filing Date: 2014-12-23
Classification: A61F,A61L

Abstract:
1. An implantable stent comprising: a tubular member including an electrically conducting substrate and having an interior surface and an exterior surface, at least one of said surfaces being hydrophobic to a body fluid in that the contact angle between a droplet of said fluid and said at least one surface is greater than 90°, and a region of said at least one surface including an array of spaced-apart microstructures or nanostructures that covers first portions of said surface and leaves second portions exposed, said array causing said region to have a dynamically controllable hydrophobicity, said array forming interstices in the spaces between said microstructures or nanostructures, a chemically active substance adhered to at least one of said exposed second portions, said substance comprising a pharmacological agent or a drug, said electrically conductive substrate being configured to be electrically isolated from body fluid in contact with said array of microstructures or nanostructures, a control device affixed to said tubular member for varying said hydrophobicity, wherein said control device is capable of applying a voltage between said array and said substrate to vary the penetration of said interstices of said array by said fluid, thereby causing release of said agent or drug into said fluid, a hydrophobic layer covering said array within said region of said at least one surface, said layer being hydrophobic to said body fluid in that the contact angle between a droplet of said fluid and said at least one surface is greater than 90°, and said electrically conductive substrate and an electrically insulative layer disposed between substrate and said hydrophobic layer, said array being formed in said substrate.