Methods and systems for applying therapeutic agent to a medical device

Abstract

In methods and systems for applying a coating to a medical device, such as a coating comprising a therapeutic agent, electrons may be transferred from an electrode to ionize a therapeutic agent dissolved in an electrolytic solution. The ionized therapeutic agent may then be electrochemically delivered to the medical device. The medical device may be a stent, which may have a porous surface.

1 . A method for coating at least a portion of a medical device comprising:
 transferring electrons from an electrode to ionize a therapeutic agent dissolved in an electrolytic solution; and   electrochemically depositing the ionized therapeutic agent onto the medical device, thereby forming a coating with the therapeutic agent on the medical device.   
     
     
         2 . The method of  claim 1  further comprising dissolving a measured amount of therapeutic agent into the electrolytic solution. 
     
     
         3 . The method of  claim 1  further comprising dissolving a measured amount of at least a second therapeutic agent in the electrolytic solution. 
     
     
         4 . The method of  claim 1  wherein the step of transferring electrons comprises introducing a voltage source having a measured voltage. 
     
     
         5 . The method of  claim 4  wherein the voltage source polarizes the electrode. 
     
     
         6 . The method of  claim 1  further comprising charging the medical device with a charge opposite to that of the ionized therapeutic agent. 
     
     
         7 . The method of  claim 1  wherein the electrolytic solution is at least one of an aqueous based and alcohol based solution. 
     
     
         8 . The method of  claim 1  wherein the electrolytic solution is a phosphate buffer saline solution. 
     
     
         9 . The method of  claim 1  wherein the therapeutic agent is paclitaxel. 
     
     
         10 . The method of  claim 1  wherein the medical device is a stent. 
     
     
         11 . A method for loading at least a portion of a medical device with a therapeutic agent comprising:
 transferring electrons from an electrode to ionize a therapeutic agent dissolved in an electrolytic solution; and   electrochemically depositing the ionized therapeutic agent into at least one porous region of the medical device, thereby loading the at least one porous region with the therapeutic agent.   
     
     
         12 . The method of  claim 11  further comprising dissolving a measured amount of therapeutic agent in the electrolytic solution. 
     
     
         13 . The method of  claim 12  further comprising dissolving a measured amount of at least a second therapeutic agent in the electrolytic solution. 
     
     
         14 . The method of  claim 11  further comprising charging the medical device with a charge opposite to that of the ionized therapeutic agent. 
     
     
         15 . The method of  claim 11  wherein the at least one porous region is two porous regions. 
     
     
         16 . The method of  claim 11  wherein the at least one porous region is a porous coating. 
     
     
         17 . The method of  claim 11  wherein the medical device is porous. 
     
     
         18 . A method for delivering a therapeutic agent to at least a portion of a medical device comprising:
 providing a medical device;   providing an electrode;   immersing the medical device and the electrode within an electrolytic solution including the therapeutic agent dissolved therein;   introducing a voltage source to polarize the electrode;   transferring electrons from the electrode to ionize the therapeutic agent in the electrolytic solution; and   electrochemically delivering the ionized therapeutic agent to the medical device.   
     
     
         19 . The method of  claim 18  wherein the therapeutic agent is loaded into a porous region of the medical device. 
     
     
         20 . The method of  claim 19  wherein the porous region is a porous coating layer. 
     
     
         21 . A system for coating at least a portion of a medical device comprising:
 a voltage source;   an electrochemical cell including an electrolytic solution having a therapeutic agent dissolved therein;   an electrode positioned within the electrolytic solution, the electrode connected to the voltage source and configured to transfer electrons to ionize the therapeutic agent; and   a medical device connected to the voltage source and positioned within the electrolytic solution,   wherein the ionized therapeutic agent is electrochemically deposited onto the medical device to form a coating with the therapeutic agent on the medical device when current is applied.   
     
     
         22 . The method of  claim 21  wherein the ionized therapeutic agent is electrochemically deposited onto a stent. 
     
     
         23 . The method of  claim 21  wherein the stent has a porous surface.