Method of making a radioactive stent

Abstract

The present invention provides a method for preparing an implantable, medical device having at least one radioactive metallic surface. The method comprises the steps of depositing a radioactive metal layer onto the surface of the device. The metal layer comprises a radioactive metal that emits beta particles and that has a half-life of between 2 hours and 7 days and a maximum beta energy of between 0.7 and 2.3 MeV. In one embodiment, the radioactive layer is deposited by electroplating the radioactive metal and a carrier metal onto the metallic surface. In another embodiment, the method further comprises the step of electroplating a second metallic layer comprising a barrier metal onto the radioactive metal layer. The present invention also provides an implantable medical device comprising a surface having a metallic surface comprising a radioactive metallic coating thereon. The coating comprises a radioactive layer comprising a radioactive metal that emits beta-particles. The radioactive metal has a half-life of between 2 hours and 7 days and an energy level of from about 0.7 MeV to 2.3 MeV. In one embodiment the radioactive layer further comprises a carrier metal. In another embodiment, the coating further comprises a second layer deposited on the radioactive layer. The second layer comprises a biocompatible metal. In a preferred embodiment the medical device is a stent. The present invention also relates to a system for applying the radioactive coating to the implantable medical device. The system comprises a package and a sterile electroplating cell contained within the package. The electroplating cell comprises a wall defining a chamber and an electrode attached to the inside wall of the cell or embedded in the inside wall of the cell, so that at least a portion of the electrode is in communication with the chamber. The system further comprises a conductive fastener for electrically connecting the metallic medical device to the power supply and positioning the device within the chamber.

Dependencies are inferred from the claim text.