Metal alloys for medical devices

• US 7,488,444 B2
• Filed: 01/24/2006
• Issued: 02/10/2009
• Est. Priority Date: 03/03/2005
• Status: Active Grant

• Current Assignee: Mirus LLC
• Original Assignee: Icon Medical Corp. (ICON Interventional Systems, Inc.)
• Inventors: Furst, Joseph G., Patel, Udayan, Buckman, Raymond W. Jr.
• Primary Examiner(s): King; Roy
• Assistant Examiner(s): Shevin; Mark L
• Application Number:
  US11/338,265
• Publication Number:
  US 20060200226A1
• Time in Patent Office: 1,113 Days
• Field of Search: None
• US Class Current: 420/429
• 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: A61P 35/00 Antineoplastic agents
• CPC Class Codes: A61P 37/06 Immunosuppressants, e.g. drugs for graft rejection
• CPC Class Codes: A61P 43/00 Drugs for specific purposes, not provided for in groups A61P1/00-A61P41/00
• CPC Class Codes: A61P 7/02 Antithrombotic agents; Anticoagulants; Platelet aggregation inhibitors
• CPC Class Codes: A61P 9/00 Drugs for disorders of the cardiovascular system
• CPC Class Codes: B22F 1/09 Mixtures of metallic powders
• CPC Class Codes: B22F 2003/248 Thermal after-treatment
• CPC Class Codes: B22F 2201/01 Reducing atmosphere
• CPC Class Codes: B22F 2201/10 Inert gases
• CPC Class Codes: B22F 2201/20 Use of vacuum
• CPC Class Codes: B22F 2998/00 Supplementary information concerning processes or compositions relating to powder metallurgy
• CPC Class Codes: B22F 2998/10 Processes characterised by the sequence of their steps
• CPC Class Codes: B22F 2999/00 Aspects linked to processes or compositions used in powder metallurgy
• CPC Class Codes: B22F 3/04 by applying fluid pressure , e.g. by cold isostatic pressing [CIP]
• CPC Class Codes: B22F 3/10 Sintering only
• CPC Class Codes: B22F 3/16 in successive or repeated steps
• CPC Class Codes: B22F 3/20 by extruding
• CPC Class Codes: B22F 3/24 After-treatment of workpieces or articles B22F3/1146 takes precedence
• CPC Class Codes: B22F 5/10 of articles with cavities or holes, not otherwise provided for in the preceding subgroups
• CPC Class Codes: B22F 5/106 : Tube or ring forms
• CPC Class Codes: C22C 27/00 : Alloys based on rhenium or a refractory metal not mentioned in groups C22C14/00 or C22C16/00
• CPC Class Codes: C22C 27/04 : Alloys based on tungsten or molybdenum
• CPC Class Codes: C22C 30/00 : Alloys containing less than 50% by weight of each constituent
• CPC Class Codes: C22F 1/18 : High-melting or refractory metals or alloys based thereon
• CPC Class Codes: Y10S 606/907 : Composed of particular material or coated

Abstract

A medical device that is at least partially formed of a novel metal alloy, which novel metal alloy improves the physical properties of the medical device.

Claims

1. A medical device that is at least partially formed of a metal alloy which improves the strength and ductility of the medical device, said metal alloy including at least about 95 weight percent of a solid solution, said metal alloy including 45-50 weight percent rhenium and 50-55 weight percent molybdenum, said metal alloy including carbon and oxygen and having a carbon to oxygen atomic ratio of at least about 2:

1, said metal alloy having a nitrogen content of less than about 20 ppm, a carbon content of less than about 150 ppm, and an oxygen content of less than about 50 ppm, said metal alloy having an average yield strength of at least about 98 ksi and an average ultimate tensile strength of at least about 100 ksi, said metal alloy having an average grain size of over 5 ASTM, said metal alloy having an average tensile elongation of at least about 25% said metal alloy having a carbon to nitrogen atomic ratio of less than about 40;

1 and an oxygen to nitrogen atomic ratio of less than about 30;

1, at least one region of said medical device includes at least one biological agent.

2. The medical device as defined in claim 1, wherein said metal alloy including at least about 99 weight percent of a solid solution, said solid solution including at least 95 weight percent rhenium and molybdenum and an additional metal, said additional metal constituting less than about 2 weight percent of said solid solution said additional metal selected from the group consisting of titanium, yttrium, zirconium, or mixtures thereof.

3. The medical device as defined in claim 1, wherein said metal alloy metal alloy includes a plurality of second phase particles, said second phase particles including carbides, carbo-nitrides, oxides or mixtures thereof.

4. The medical device as defined in claim 1, wherein said metal alloy has an average grain size of over 5-10 ASTM.

5. The medical device as defined in claim 1, wherein said metal alloy has an average density of at least 13 gm/cc.

6. The medical device as defined in claim 1, wherein said metal alloy includes about 46-49 weight percent rhenium and about 51-54 weight percent molybdenum.

7. The medical device as defined in claim 1, wherein said medical device is a stent, graft, valve, screw, nail, rod, PFO device, prosthetic device, sheath, guide wire, balloon catheter, hypotube, catheter, electrophysiology catheter, staple or cutting device.

8. The medical device as defined in claim 1, wherein said at least one biological agent includes trapidil, trapidil derivatives, taxol, taxol derivatives, cytochalasin, cytochalasin derivatives, paclitaxel, paclitaxel derivatives, rapamycin, rapamycin derivatives, GM-CSF, GM-CSF derivatives, and combinations thereof.

9. The medical device as defined in claim 1, wherein at least one region of said medical device includes at least one polymer.

10. The medical device as defined in claim 9, wherein said at least one polymer at least partially coats said at least biological agent, encapsulates said at least biological agent, and combinations thereof.

11. The medical device as defined in claim 10, wherein said at least one polymer controllably releases at least one of said biological agents.

12. The medical device as defined in claim 9, wherein said at least one polymer includes parylene, a parylene derivative, chitosan, a chitosan derivative, PLGA, a PLGA derivative, PLA, a PLA derivative, PEVA, a PEVA derivative, PBMA, a PBMA derivative, POE, a POE derivative, PGA, a PGA derivative, PLLA, a PLLA derivative, PAA, a PAA derivative, PEG, a PEG derivative, or combinations thereof.

13. The medical device as defined in claim 1, wherein said medical device includes at least one micro-structure in an outer surface of said medical device.

14. The medical device as defined in claim 13, wherein said at least one micro-structure is at least partially formed of, includes, or combinations thereof, a material consisting of a polymer, a biological agent, or combinations thereof.

15. The medical device as defined in claim 2, wherein said metal alloy metal alloy includes a plurality of second phase particles, said second phase particles including carbides, carbo-nitrides, oxides, and mixtures thereof.

16. The medical device as defined in claim 15, wherein said metal alloy has an average grain size of about 5-10 ASTM.

17. The medical device as defined in claim 16, wherein said metal alloy has an average density of at least 13 gm/cc.

18. The medical device as defined in claim 17, wherein said metal alloy includes about 46-49 weight percent rhenium and about 51-54 weight percent molybdenum.

19. The medical device as defined in claim 18, wherein at least one region of said medical device includes at least one polymer, said at least one polymer at least partially cost said at least biological agent, encapsulates said at least biological agent, and combinations thereof.

20. The medical device as define in claim 19, wherein said at least one polymer controllably releases at least one of said biological agents.

21. The medical device as defined in claim 18, wherein said medical device includes at least one micro-structure in an outer surface of said medical device.

22. The medical device as defined in claim 21, wherein said at least one micro-structure is at least partially formed of, includes, or combinations thereof, a material consisting of a polymer, a biological agent, and combinations thereof.

23. The medical device as defined in claim 1, wherein said solid solution includes by weight percent:

24. The medical device as defined in claim 17, wherein said solid solution includes by weight percent:

25. The medical device as defined in claim 1, wherein said metal alloy including carbon and oxygen and having a carbon to oxygen atomic ratio of about 2.5-10:

1.

26. The medical device as defined in claim 18, wherein said metal alloy including carbon and oxygen and having a carbon to oxygen atomic ratio of about 2.5-10:

1.

27. The medical device as defined in claim 1, wherein said metal alloy has an average grain size of about 6-9 ASTM.

28. The medical device as defined in claim 18, wherein said metal alloy has an average grain size of about 6-9 ASTM.

29. The medical device as defined in claim 1, wherein said atomic ratio of carbon to oxygen in said metal alloy is less than about 50:

1.

30. The medical device as defined in claim 18, wherein said atomic ratio of carbon to oxygen in said metal alloy is less than about 50:

1.

31. The medical device as defined in claim 1, wherein said metal alloy includes titanium.

32. The medical device as defined in claim 18, wherein said metal alloy includes titanium.

33. The medical device as defined in claim 31, wherein said metal alloy includes titanium and zirconium, said titanium and zirconium having a weight ratio of about 1.2-5:

1.

34. The medical device as defined in claim 32, wherein said metal alloy includes titanium and zirconium, said titanium and zirconium having a weight ratio of about 1.2-5:

1.