Medical devices and methods of making the same

• US 7,682,649 B2
• Filed: 04/20/2007
• Issued: 03/23/2010
• Est. Priority Date: 10/02/2002
• Status: Expired due to Fees

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Inventors: Schmidt, Karl Morris, Chandrasekaran, Verivada, Molina, Christopher Torres
• Primary Examiner(s): Barr; Michael
• Assistant Examiner(s): BOWMAN, ANDREW J
• Application Number:
  US11/738,229
• Publication Number:
  US 20070190231A1
• Time in Patent Office: 1,068 Days
• Field of Search: 428/423.1, 428/655, 106/1.2, 427/2.24, 419/28, 514/312
• US Class Current: 427/2.24
• CPC Class Codes: A61B 90/39 Markers, e.g. radio-opaque or breast lesions markers
• CPC Class Codes: A61F 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2002/91525 within the whole structure different bands showing different meander characteristics, e.g. frequency or amplitude
• CPC Class Codes: A61F 2002/91533 characterised by the phase between adjacent bands
• CPC Class Codes: A61F 2002/91566 connected trough to trough
• CPC Class Codes: A61F 2002/91575 connected peak to trough
• CPC Class Codes: A61F 2250/0032 differing in radiographic density
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61L 31/088 Other specific inorganic materials not covered by A61L31/084 or A61L31/086
• CPC Class Codes: A61L 31/18 Materials at least partially X-ray or laser opaque
• CPC Class Codes: C23C 14/16 on metallic substrates or on substrates of boron or silicon
• CPC Class Codes: C23C 14/46 by ion beam produced by an external ion source
• CPC Class Codes: C23C 28/00 Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
• CPC Class Codes: C23C 28/021 including at least one metal alloy layer
• CPC Class Codes: C23C 28/023 only coatings of metal elements only
• CPC Class Codes: C23C 28/028 Including graded layers in composition or in physical properties, e.g. density, porosity, grain size
• CPC Class Codes: C23C 28/321 with at least one metal alloy layer
• CPC Class Codes: C23C 28/322 only coatings of metal elements only
• CPC Class Codes: C23C 28/325 with layers graded in composition or in physical properties
• CPC Class Codes: C23C 28/34 : including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates
• CPC Class Codes: C23C 28/341 : with at least one carbide layer
• CPC Class Codes: C23C 28/345 : with at least one oxide layer
• CPC Class Codes: C23C 28/36 : including layers graded in composition or physical properties
• CPC Class Codes: C23C 28/42 : characterized by the composition of the alternating layers
• CPC Class Codes: C23C 8/10 : Oxidising
• CPC Class Codes: C25D 5/48 : After-treatment of electroplated surfaces
• CPC Class Codes: Y10T 428/12 : All metal or with adjacent metals
• CPC Class Codes: Y10T 428/12771 : Transition metal-base component
• CPC Class Codes: Y10T 428/2995 : Silane, siloxane or silicone coating
• CPC Class Codes: Y10T 428/31544 : Addition polymer is perhalogenated
• CPC Class Codes: Y10T 428/31551 : Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]
• CPC Class Codes: Y10T 428/31573 : Next to addition polymer of ethylenically unsaturated monomer
• CPC Class Codes: Y10T 428/31576 : Ester monomer type [polyvinylacetate, etc.]
• CPC Class Codes: Y10T 428/31678 : Of metal
• CPC Class Codes: Y10T 428/31692 : Next to addition polymer from unsaturated monomers

Abstract

An endoprosthesis, such as a stent, having a layer that can enhance the biocompatibility of the endoprosthesis, and methods of making the endoprosthesis are disclosed.

Claims

1. A method of making a stent including a member, the method comprising:

forming an outer layer of the stent on the member, the outer layer of the stent comprising an alloy comprising a radiopaque metal element and a second metal element, wherein the radiopaque metal element is selected from a group consisting of gold, palladium, and platinum; and

oxidizing a portion of the alloy of the outer layer.

2. The method of claim 1, wherein oxidizing the portion comprises forming an oxide from the outer layer.

3. The method of claim 1, wherein oxidizing the portion comprises forming a nitride from the outer layer.

4. The method of claim 1, further comprising forming a radiopaque layer comprising the radiopaque metal element.

5. The method of claim 1, wherein the outer layer is formed with a compositional gradient.

6. The method of claim 1, wherein the outer layer is formed by a process selected from the group consisting of physical vapor deposition, chemical vapor deposition, and electrodeposition.

7. The method of claim 1, wherein oxidizing the portion of the outer layer is performed by electropolishing.

8. The method of claim 1, wherein oxidizing the portion of the outer layer is performed by heating the outer layer in an oxidizing environment.

9. The method of claim 1, wherein oxidizing the portion of the outer layer is performed by ion implanting oxygen in the outer layer and heating the outer layer.

10. The method of claim 1, further comprising forming a polymeric layer on the outer layer.

11. The method of claim 1, further comprising forming a drug-releasing layer on the outer layer.

12. The method of claim 1, wherein the radiopaque metal is capable of attenuating an incident X-ray beam by more than about 70%.

13. The method of claim 1, wherein the second metal element is selected from the group consisting of titanium, chromium, palladium, niobium, and silicon.

14. The method of claim 1, wherein the member comprises a material selected from the group consisting of stainless steel and nickel-titanium alloy.

15. The method of claim 1, wherein the outer layer defines an outer surface of the member.

16. The method of claim 1, further comprising forming a second layer comprising the radiopaque metal element, the second layer disposed inwardly of the outer layer.

17. The method of claim 16, wherein the outer layer has a lower oxidation potential than an oxidation potential of the second layer.

18. A method of making a stent including a member, the method comprising:

forming a first layer of a stent comprising a radiopaque metal element on the member, wherein the radiopaque metal element is selected from the group consisting of gold, platinum, and palladium;

forming a second layer of a stent comprising an alloy of the radiopaque metal element and a second metal element;

oxidizing a portion of the alloy of the second layer.