Multi-layered radiopaque coating on intravascular devices

• US 20020138130A1
• Filed: 11/15/2001
• Published: 09/26/2002
• Est. Priority Date: 11/20/2000
• Status: Active Grant

• Current Assignee: Implant Sciences Corporation
• Original Assignee: Implant Sciences Corporation
• Inventors: Sahagian, Richard
• Granted Patent: US 7,077,837 B2
• Time in Patent Office: Days
• US Class Current: 623/1.15
• CPC Class Codes: A61B 90/39 Markers, e.g. radio-opaque or breast lesions markers
• CPC Class Codes: A61F 2/86 Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61L 31/18 Materials at least partially X-ray or laser opaque

Abstract

Intravascular devices having a radiopaque layer thereon for visualization are provided. The devices further includes a capping layer on the radiopaque layer to prevent exposure of the radiopaque material to surrounding tissues. A method of coating the device is also provided. The method includes using an unbalanced magnetic field magnetron to generate, from a source, metal atoms for coating and bombarding ions for compressing deposited metal atoms to the surface of the device.

Claims

1. An intravascular device comprising:

a substrate surface;

a layer of a radiopaque material on the substrate surface and having a thickness sufficient to permit visualization; and

a capping layer positioned on the layer of radiopaque material to prevent exposure of the layer of radiopaque material to surrounding tissue.

2. An intravascular device as set forth in claim 1, wherein the substrate surface comprises a metallic material.

3. An intravascular device as set forth in claim 2, wherein the metallic material includes one of stainless steel, nickel-based steel, cobalt-chrome, titanium alloys, and nitinol.

4. An intravascular device as set forth in claim 2, wherein the metallic material is flexible.

5. An intravascular device as set forth in claim 1, wherein the layer of radiopaque material is made from a pliable and malleable material to provide the layer with flexibility.

6. An intravascular device as set forth in claim 1, wherein the layer of radiopaque material comprises gold.

7. An intravascular device as set forth in claim 1, wherein the layer of radiopaque material has a thickness ranging from about 1 micron to about 15 microns.

8. An intravascular device as set forth in claim 1, wherein the capping layer comprises a biocompatible material.

9. An intravascular device as set forth in claim 8, wherein the biocompatible material comprises a metallic material.

10. An intravascular device as set forth in claim 9, wherein the metallic material includes one of platinum alloys, platinum-iridium, palladium, and tantalum.

11. An intravascular device as set forth in claim 1, wherein the capping layer has a thickness ranging from about 0.5 micron to about 1.0 micron.

12. An intravascular device as set forth in claim 1, further including a transition layer situated between the capping layer and the layer of radiopaque material to enhance bonding between the capping layer and the layer of radiopaque material.

13. An intravascular device as set forth in claim 1, wherein the transition layer comprises a mixture of the radiopaque material and material comprising the capping layer.

14. An intravascular device as set forth in claim 13, wherein the transition layer comprises a mixture of gold and platinum-iridium.

15. An intravascular device as set forth in claim 13, wherein the transition layer has a thickness ranging from about 0.25 microns to about 0.5 microns.

16. An intravascular device as set forth in claim 1, further including an adhesion layer between the layer of radiopaque material and the outer substrate surface to enhance bonding between the layer of radiopaque material and the outer substrate surface.

17. An intravascular device as set forth in claim 16, wherein the adhesion layer comprises a mixture of gold and chromium-palladium.

18. An intravascular device as set forth in claim 16, wherein the adhesion layer has a thickness ranging from about 0.25 microns to about 0.5 microns.

20. An intravascular stent as set forth in claim 19, wherein the layer of radiopaque material is made from a pliable and malleable material to provide the layer with flexibility.

21. An intravascular stent as set forth in claim 19, wherein the layer of radiopaque material comprises gold.

22. An intravascular stent as set forth in claim 19, wherein the capping layer comprises a biocompatible material.

23. An intravascular stent as set forth in claim 22, wherein the biocompatible material includes one of platinum alloys, platinum-iridium, palladium, and tantalum.

24. An intravascular stent as set forth in claim 19, wherein the transition layer comprises a mixture of the radiopaque material and material comprising the capping layer.

25. An intravascular stent as set forth in claim 19, wherein the transition layer comprises a mixture of gold and platinum-iridium.

27. An intravascular stent as set forth in claim 26, wherein the layer of radiopaque material comprises gold.

28. An intravascular stent as set forth in claim 26, wherein the adhesion layer comprises a mixture of gold and chromium-palladium.

29. An intravascular stent as set forth in claim 26, wherein the capping layer includes one of platinum alloys, platinum-iridium, palladium, and tantalum.

30. An intravascular stent as set forth in claim 26, further including a transition layer situated between the capping layer and the layer of radiopaque material to enhance bonding between the capping layer and the layer of radiopaque material.

31. An intravascular stent as set forth in claim 30, wherein the transition layer comprises a mixture of gold and platinum-iridium.

19. An intravascular stent comprising:

a flexible expandable body having a surface;

a layer of a radiopaque material on the surface and having a thickness sufficient to permit visualization;

a capping layer positioned on the layer of radiopaque material to prevent exposure of the layer of radiopaque material to surrounding tissue; and

a transition layer situated between the capping layer and the layer of radiopaque material to enhance bonding between the capping layer and the layer of radiopaque material.

26. An intravascular stent comprising:

A flexible expandable body having a surface;

a layer of a radiopaque material on the surface and having a thickness sufficient to permit visualization;

an adhesion layer between the layer of radiopaque material and the surface to enhance bonding between the layer of radiopaque material and the surface.

a capping layer positioned on the layer of radiopaque material to prevent exposure of the layer of radiopaque material to surrounding tissue.

32. A method for coating an intravascular device, the method comprising:

providing an intravascular device having a substrate surface;

generating a flux of atoms of a radiopaque material and a flux of bombarding ions;

directing the flux of atoms of the radiopaque material and the flux of bombarding ions in a co-linear fashion toward the substrate surface;

depositing the atoms on to the substrate surface; and

permitting the bombarding ions to impact the atoms to the substrate surface, so as to provide a substantially uniform layer of radiopaque material.

33. A method as set forth in claim 32, further comprising:

generating a flux of first metal atoms;

directing the flux of first metal atoms and a flux of bombarding ions in a co-linear fashion toward the layer of radiopaque material;

depositing the first metal atoms on to the layer of radiopaque material; and

permitting the bombarding ions to impact the first metal atoms to the radiopaque material, so as to provide a substantially uniformly capping layer.

34. A method as set forth in claim 33, further comprising:

depositing a mixture of the atoms of radiopaque material and the first metal atoms between the layer of radiopaque material and the capping layer; and

generating a transition layer therebetween.

35. A method as set forth in claim 34, wherein the step of depositing includes:

reducing an amount at which the atoms of the radiopaque material are being deposited; and

increasing an amount at which the metal atoms are being deposited.

36. A method as set forth in claim 33, further comprising:

depositing a mixture of second metal atoms and atoms of the radiopaque material between the substrate surface and the layer of radiopaque material; and

generating an adhesion layer therebetween.

37. A method as set forth in claim 36, wherein the step of depositing includes:

reducing an amount at which the second metal atoms are being deposited; and

increasing an amount at which the atoms of the radiopaque material are being deposited.