MEDICAL ARTICLES THAT STIMULATE ENDOTHELIAL CELL MIGRATION

• US 20090143856A1
• Filed: 11/29/2007
• Published: 06/04/2009
• Est. Priority Date: 11/29/2007
• Status: Active Grant

• Current Assignee: Boston Scientific Corporation
• Original Assignee: Boston Scientific Corporation
• Inventors: Nielson, Eric, VanCamp, Daniel, Chandrasekaran, Verivada, Radhakrishnan, Rajesh
• Granted Patent: US 8,118,857 B2
• Time in Patent Office: Days
• US Class Current: 623/1.490
• CPC Class Codes: A61L 27/04 Metals or alloys
• CPC Class Codes: A61L 27/50 Materials characterised by their function or physical properties , e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
• CPC Class Codes: A61L 31/022 Metals or alloys
• CPC Class Codes: A61L 31/14 Materials characterised by their function or physical properties , e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
• CPC Class Codes: A61N 1/30 Apparatus for iontophoresis, i.e. transfer of media in ionic state by an electromotoric force into the body, or cataphoresis
• CPC Class Codes: A61N 1/326 for promoting growth of cells, e.g. bone cells

Abstract

A medical article that includes (a) an electronically conductive substrate having a specific conductivity of at least 1 μS/cm and (b) a galvanic couple that includes a first member and a second member arranged in sufficient proximity to each other to generate a localized electric field under physiological conditions. The first and second members are selected such that the galvanic couple exhibits an average plateau current density of at least 25 microamps/cm² when short circuited in a zero resistance ammeter test at room temperature using a saline electrolyte.

Claims

1. A medical article comprising (a) an electronically conductive substrate having a specific conductivity of at least 1 μ

S/cm and (b) a galvanic couple that comprises a first member and a second member arranged in sufficient proximity to each other to generate a localized electric field under physiological conditions, wherein the first and second members are selected such that the galvanic couple exhibits an average plateau current density of at least 25 microamps/cm² when short circuited in a zero resistance ammeter test at room temperature using a saline electrolyte.

2. A medical article according to claim 1 wherein the first and second members are selected such that the galvanic couple exhibits an average plateau current density of at least 250 microamps/cm² when short circuited in a zero resistance ammeter test at room temperature using a saline electrolyte.

3. A medical article according to claim 1 wherein the substrate has a specific conductivity of at least 1 mS/cm.

4. A medical article according to claim 1 wherein the first member of the galvanic couple comprises a noble metal.

5. A medical article according to claim 4 wherein the noble metal is selected from the group consisting of platinum, iridium, ruthenium, and combinations thereof.

6. A medical article according to claim 1 wherein the first member of the galvanic couple comprises a refractory metal.

7. A medical article according to claim 6 wherein the refractory metal is selected from the group consisting of titanium, hafnium, zirconium, and niobium, and combinations thereof.

8. A medical article according to claim 1 wherein the second member of the galvanic couple is a metal selected from the group consisting of alkali metals, alkaline earth metals, zinc, and combinations thereof.

9. A medical article according to claim 8 wherein the second member of the galvanic couple comprises zinc.

10. A medical article according to claim 1 wherein the first member of the galvanic couple is selected from the group consisting of platinum, iridium, ruthenium, and combinations thereof, and the second member of the galvanic couple is selected from the group consisting of zinc, magnesium, and combinations thereof.

11. A medical article according to claim 1 wherein the substrate is selected from the group consisting of metals, electrically conductive polymers, electrically conductive polymer composites, and combinations thereof.

12. A medical article according to claim 1 wherein the substrate comprises an outer surface, an inner surface, and pores extending between the outer and inner surfaces, wherein one of the members of the galvanic couple is provided on the outer surface of the substrate and the other member of the galvanic couple is provided on the inner surface of the substrate.

13. A medical article according to claim 1 wherein the one of the members of the galvanic couple is provided in the form of a layer deposited on the substrate and the other member of the galvanic couple is provided in the form of particles in a matrix deposited on the substrate.

14. A medical article according to claim 13 wherein the matrix comprises a biodegradable polymer or metal matrix.

15. A medical article according to claim 1 wherein the first and second members of the galvanic couple are deposited on the substrate in the form of a pattern along the length of the article.

16. A medical article according to claim 1 wherein the article is an implantable medical device.

17. A medical article according to claim 16 wherein the implantable medical device is a stent.

18. A medical article according to claim 16 wherein the implantable medical device is a vascular graft.

19. A medical article according to claim 1 wherein the article is an external wound healing article.

20. A medical article according to claim 19 wherein the article is a bandage in which the galvanic couple is incorporated in a fabric arranged in electrical contact with the electrically conductive substrate.

21. An implantable medical device comprising (a) an electronically conductive substrate having a specific conductivity of at least 1 mS/cm selected from the group consisting of metals, electrically conductive polymers, electrically conductive polymer composites, and combinations thereof;

and (b) a galvanic couple that comprises a (i) first member selected from the group consisting of platinum, iridium, ruthenium, and combinations thereof, and (ii) a second member selected from the group consisting of zinc, magnesium, and combinations thereof, wherein the first and second members are arranged in sufficient proximity to each other to generate a localized electric field under physiological conditions, and the first and second members are selected such that the galvanic couple exhibits an average plateau current density of at least 250 microamps/cm² when short circuited in a zero resistance ammeter test at room temperature using a saline electrolyte.

22. An implantable medical device according to claim 21 wherein the device is a stent.