Metallic structures incorporating bioactive materials and methods for creating the same

• US 20060115512A1
• Filed: 09/09/2005
• Published: 06/01/2006
• Est. Priority Date: 11/28/2003
• Status: Abandoned Application

• Current Assignee: Medlogics Device Corporation
• Original Assignee: Medlogics Device Corporation
• Inventors: Lee, Michael J., Peacock, James C. III, Klein, Richard L.
• Application Number:
  US11/223,234
• Publication Number:
  US 20060115512A1
• Time in Patent Office: Days
• US Class Current: 424/422
• CPC Class Codes: A61F 2210/0004 bioabsorbable
• CPC Class Codes: A61F 2250/0068 the pharmaceutical product being in a reservoir
• CPC Class Codes: A61L 2300/41 Anti-inflammatory agents, e.g. NSAIDs
• CPC Class Codes: A61L 2300/416 Anti-neoplastic or anti-proliferative or anti-restenosis or anti-angiogenic agents, e.g. paclitaxel, sirolimus
• CPC Class Codes: A61L 2300/45 Mixtures of two or more drugs, e.g. synergistic mixtures
• CPC Class Codes: A61L 2300/604 Biodegradation
• CPC Class Codes: A61L 31/12 Composite materials, i.e. containing one material dispersed in a matrix of the same or different material
• CPC Class Codes: A61L 31/146 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 31/148 Materials at least partially resorbable by the body
• CPC Class Codes: A61L 31/16 Biologically active materials, e.g. therapeutic substances A61L31/047 takes precedence

Abstract

Disclosed herein are methods to create medical devices and implantable medical devices with an electrochemically engineered porous surface that contains one or more bioactive materials to form bioactive composite structures. The bioactive composite structures are prepared using electrochemical codeposition methods to create metallic layers with pores that can be loaded with bioactive materials. In one use, the implantable medical devices of the present invention include stents with bioactive composite structure coatings.

Claims

1. A method comprising:

providing a bath comprising metal ions and erodable particles;

contacting said bath with a substrate;

forming a composite structure on said substrate using an electrochemical process;

removing said erodable particles from said composite structure after said formation of said composite structure thus leaving pores in said structure; and

loading at least one bioactive material into said pores thus forming a biocomposite structure.

2. The method according to claim 1, wherein said electrochemical process is selected from the group consisting of electrolytic processes, electroless processes and electrophoretic processes.

3. The method according to claim 1, wherein said bath further comprises at least one bioactive material and said formed composite structure after said contacting is a bioactive composite structure.

4. The method according to claim 1, wherein said erodable particles are selected from the group consisting of polytetrafluoroethylene polymer particles, polytetrafluoroethylene oligomer particles, tetrafluoroethylene-hexafluoropropylene copolymer particles, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer particles, fluorinated graphite particles, fluorinated pitch particles, graphite particles, molybdenum disulfide particles, boron nitride particles and combinations thereof.

5. The method according to claim 1, wherein said bath further comprises a low viscosity silicone glycol surfactant.

6. The method according to claim 1, wherein said bath further comprises glycerol.

7. The method according to claim 1, wherein said bath further comprises a low viscosity silicone glycol surfactant and glycerol.

8. The method of claim 1, wherein said substrate is a stent.

9. The method of claim 1, further comprising forming a topcoat over said biocomposite structure.

10. A medical device comprising a bioactive composite structure wherein said bioactive composite structure is formed by:

providing a bath comprising metal ions and erodable particles;

contacting said bath with a substrate;

forming a composite structure on said substrate using an electroless process;

removing said erodable particles from said composite structure after said formation of said composite structure thus leaving pores in said structure; and

loading at least one bioactive material into said pores thus forming a biocomposite structure.

11. The medical device according to claim 10, wherein said bath further comprises at least one bioactive material and said formed composite structure after said contacting is a bioactive composite structure.

12. The medical device according to claim 10, wherein said erodable particles are selected from the group consisting of polytetrafluoroethylene polymer particles, polytetrafluoroethylene oligomer particles, tetrafluoroethylene-hexafluoropropylene copolymer particles, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer particles, fluorinated graphite particles, fluorinated pitch particles, graphite particles, molybdenum disulfide particles, boron nitride particles and combinations thereof.

13. The medical device according to claim 10, wherein said bath further comprises a low viscosity silicone glycol surfactant.

14. The medical device according to claim 10, wherein said bath further comprises glycerol.

15. The medical device according to claim 10, wherein said bath further comprises a low viscosity silicone glycol surfactant and glycerol.

16. The medical device according to claim 10, wherein said substrate is a stent.

17. The medical device according to claim 10, further comprising forming a topcoat over said biocomposite structure.

18. A method comprising:

providing a first bath comprising metal ions and erodable particles wherein said metal ions and said erodable particles in said first bath are provided at a first ratio;

contacting a substrate with said first bath;

forming a composite structure with a first concentration of metal ions and erodable particles on said substrate using an electrochemical process;

altering said first ratio between said metal ions and said erodable particles to form a second ratio;

continuing to form said composite structure on said substrate using an electrochemical process but with a second concentration of metal ions and said erodable particles;

removing said erodable particles from said composite structure after said formation of said composite structure thus leaving pores in said structure; and

loading at least one bioactive material into said pores thus forming a biocomposite structure.

19. The method according to claim 18, wherein said electrochemical process is selected from the group consisting of electrolytic processes, electroless processes and electrophoretic processes.

20. The method according to claim 18, wherein said first and/or said second bath further comprises at least one bioactive material and wherein said composite structure is a biocomposite structure.