Patent ID: 7318945
Filing Date: 2008-01-15
Classification: A61F,A61L

Abstract:
1. A method of applying a drug-polymer coating on a stent, comprising: dipping a stent framework into a first polymeric solution, wherein the first polymeric solution comprises a first polymer, a first therapeutic agent, and a first solvent, wherein the first polymer comprises a copolymer of methacrylamide, methacrylate and vinyl alcohol, the first therapeutic agent comprises 5-fluorouracil, and the first solvent comprises a mixture of chloroform and water; drying the first polymeric solution to form a thin drug-polymer layer on the stent framework; dipping the stent framework including the thin drug-polymer layer into a second polymeric solution, wherein the second polymeric solution comprises a second polymer and a second solvent, wherein the thin drug-polymer layer is insoluble in the second polymeric solution, and wherein the second polymer comprises a rigid thermoplastic polyurethane and the second solvent comprises tetrahydrofuran; drying the second polymeric solution to form a thin barrier layer on the first thin drug-polymer layer; and repeating the steps of dipping the stent framework into the first polymeric solution, drying the first polymeric solution, dipping the stent framework into the second polymeric solution, and drying the second polymeric solution until a target drug-polymer coating thickness is disposed on the stent framework.