Endoprosthesis coating

• US 8,002,823 B2
• Filed: 07/11/2007
• Issued: 08/23/2011
• Est. Priority Date: 07/11/2007
• Status: Expired due to Fees

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Inventors: Kuehling, Michael
• Primary Examiner(s): GHERBI, SUZETTE JAIME J
• Application Number:
  US11/776,320
• Publication Number:
  US 20090018639A1
• Time in Patent Office: 1,504 Days
• Field of Search: 623 115- 148, 424426-427
• US Class Current: 623/1.46
• CPC Class Codes: A61F 2/06 Blood vessels
• CPC Class Codes: A61L 31/026 Ceramic or ceramic-like structures, e.g. glasses
• CPC Class Codes: A61L 31/10 Macromolecular materials

Abstract

An endoprosthesis, such as a stent, includes anchoring regions formed of polymer that enhance adherence of a coating, e.g. a drug eluting polymer coating, to a stent surface, e.g. made of ceramic. The anchoring regions can be formed using stamping processes.

Claims

1. An endoprosthesis, comprising:

a body including a ceramic on a surface thereof

a pattern of spaced polymeric anchoring elements adhered to the ceramic, and

a polymeric coating adhered to the anchoring elements, the polymeric coating having an enhanced adherence to the ceramic through the anchoring elements and having a thickness greater than a thickness of the anchoring elements.

2. The endoprosthesis of claim 1, wherein the polymeric coating includes a drug.

3. The endoprosthesis of claim 1, wherein the ceramic is free of a polymer forming the polymeric anchoring elements.

4. The endoprosthesis of claim 1, wherein the anchoring elements extend into wells defined in the ceramic.

5. The endoprosthesis of claim 1, wherein the ceramic is an oxide or nitride.

6. The endoprosthesis of claim 1, wherein the ceramic is IROX.

7. The endoprosthesis of claim 1, wherein the thickness of the anchoring elements is about 10-90% of the thickness of the coating.

8. The endoprosthesis of claim 1, wherein the width of the anchoring elements is less than the height of the anchoring elements.

9. The endoprosthesis of claim 1, wherein the thickness of the anchoring elements is about 1 to 10 micron.

10. The endoprosthesis of claim 1, wherein the anchoring elements form a covalent bond to the ceramic.

11. The endoprosthesis of claim 10, wherein the anchoring elements are formed of silane.

12. The endoprosthesis of claim 10, wherein the anchoring elements include hydrophobic moieties.

13. The endoprosthesis of claim 1, wherein the polymeric coating is adhered to the anchoring elements without covalent bonding.

14. The endoprosthesis of claim 1, wherein the ceramic has a globular morphology.

15. The endoprosthesis of claim 1, wherein the ceramic has a defined grain morphology.

16. The endoprosthesis of claim 1, wherein the anchoring elements extend into the ceramic.

17. The endoprosthesis of claim 1, wherein the anchoring elements are substantially free of drug.

18. A method of forming an endoprosthesis, comprising:

providing an endoprosthesis including a ceramic on a surface,

applying to the ceramic on the surface an anchoring polymer,

patterning the anchoring polymer to form anchors,

applying a polymer coating to the anchors, the polymer coating having an enhanced adhesion to the ceramic through the anchors and having a thickness greater than a thickness of the anchors.

19. The method of claim 18, comprising patterning the anchoring polymer by stamping to form regions of different thickness.

20. The method of claim 19, comprising etching the anchoring polymer after stamping.

21. The method of claim 18, wherein the polymeric coating includes a drug.

22. The method of claim 18, wherein the ceramic is IROX.

23. The method of claim 18, wherein the thickness of the anchoring element is about 1 to 10 micron.

24. The method of claim 18, wherein the polymer coating is adhered to the anchoring elements without covalent bonding.

25. An endoprosthesis, comprising:

a body including a ceramic on a surface thereof

a pattern of spaced polymeric anchoring elements adhered to the ceramic, and

a polymeric coating adhered to the anchoring elements, the anchoring elements being formed of silane and forming a covalent bond to the ceramic.

26. A method of forming an endoprosthesis, comprising:

providing an endoprosthesis including a ceramic on a surface,

applying to the ceramic on the surface an anchoring polymer,

patterning the anchoring polymer to form anchors by stamping to form regions of different thickness,

applying a polymer coating to the anchors.