Biosensor membrane material

• US 20060183871A1
• Filed: 04/14/2006
• Published: 08/17/2006
• Est. Priority Date: 05/21/2003
• Status: Active Grant

• Current Assignee: Polymer Technology Group, Inc. (DSM-Firmenich AG), Konamite Limited
• Original Assignee: Isense Corporation
• Inventors: Ward, Robert S., Ward, W. Kenneth, Tian, Yuan, Anderson, Ellen, House, Jody
• Granted Patent: US 7,687,586 B2
• Time in Patent Office: Days
• US Class Current: 525/464
• CPC Class Codes: C08G 64/18 Block or graft polymers
• CPC Class Codes: C08G 77/448 containing polycarbonate sequences
• CPC Class Codes: C08G 77/458 containing polyurethane sequences

Abstract

Embodiments of the present invention provide various multipolymers and permselective membranes for use with biosensors and other implantable medical devices and prostheses. Embodiments of the present invention may provide structural strength and integrity, and further may control the influx of glucose, oxygen and/or water. Embodiments of the present invention may, for example, minimize or reduce the influx of glucose by minimizing the percentage of hydrophilic segments, which in turn minimizes the percentage of water uptake and the degree of glucose transport.

Claims

1. A biocompatible multipolymer capable of forming a glucose-limiting permselective membrane, said multipolymer having at least one soft segment, wherein less than about 10% of total soft segment weight is made up of a hydrophilic soft segment.

2. The multipolymer of claim 1, wherein said hydrophilic soft segment comprises less than about 5% of total soft segment weight.

3. The multipolymer of claim 1, wherein said hydrophilic soft segment comprises less than about 2% of total soft segment weight.

4. The multipolymer of claim 1, further comprising a biostable, hydrophobic polycarbonate soft segment.

5. The multipolymer of claim 4, wherein said polycarbonate soft segment is free of ether groups.

6. The multipolymer of claim 1, wherein said hydrophilic soft segment comprises a compound having the formula O(CH₂)_N, where N<

4.

7. The multipolymer of claim 1, wherein said hydrophilic soft segment comprises polyethylene oxide.

8. The multipolymer of claim 1, further comprising an oxygen-permeable soft segment.

9. The multipolymer of claim 8, wherein said oxygen-permeable soft segment comprises polydimethlysiloxane.

10. The multipolymer of claim 8, wherein said oxygen-permeable soft segment comprises a perfluorinated or partially fluorinated hydrocarbon.

11. The multipolymer of claim 8, wherein said oxygen-permeable soft segment comprises a perfluorinated or partially fluorinated polyalkylsiloxane.

12. The multipolymer of claim 1, further comprising surface modifying end groups.

13. The multipolymer of claim 12, wherein said surface modifying end groups comprise perfluorinated or partially fluorinated hydrocarbons.

14. The multipolymer of claim 12, wherein said surface modifying end groups comprise perfluorinated or partially fluorinated polyethers.

15. The multipolymer of claim 12, wherein said surface modifying end groups comprise perfluorinated or partially fluorinated polyalkylsiloxanes.

16. A permselective membrane, comprising:

a multipolymer having at least one soft segment, wherein less than 10% of total soft segment weight is made up of a hydrophilic soft segment.

17. The membrane of claim 16, wherein said hydrophilic soft segment comprises less than 5% of total soft segment weight.

18. The membrane of claim 16, wherein said hydrophilic soft segment comprises less than 2% of total soft segment weight.

19. The membrane of claim 16, wherein said membrane has water absorption of from 0.25-10% of dry weight.

20. The membrane of claim 16, wherein said membrane has water absorption of less than 5% of dry weight.

21. The membrane of claim 16, wherein said membrane has an average loss of sensitivity to analyte permeation of less than 10% over an oxygen tension range between 30 Torr and 150 Torr.

22. The membrane of claim 16, wherein said membrane has an average loss of sensitivity to analyte permeation of less than 5% over an oxygen tension range between 30 Torr and 150 Torr.

23. A biocompatible multipolymer, comprising:

at least one hard segment;

about 55 to 90 wt % of soft segments, including;

about 5 to 25 wt %, of total soft segment weight, of an oxygen permeable soft segment, said oxygen permeable soft segment comprising at least one fluorine-containing soft segment;

less than about 25 wt %, of total soft segment weight, of a hydrophilic soft segment; and

about 50 to 90 wt %, of total soft segment weight, of a biostable, hydrophobic soft segment.

24. The multipolymer of claim 23, wherein said hydrophilic soft segment comprises less than about 10% of total soft segment weight.

25. The multipolymer of claim 23, wherein said hydrophilic soft segment comprises less than about 5% of total soft segment weight.

26. The multipolymer of claim 23, wherein said hydrophilic soft segment comprises less than about 2% of total soft segment weight.

27. The multipolymer of claim 23, wherein said biostable, hydrophobic soft segment comprises about 60 to 80% of total soft segment weight.

28. The multipolymer of claim 23, wherein said biostable, hydrophobic soft segment comprises a polycarbonate.

29. The multipolymer of claim 28, wherein said polycarbonate soft segment is free of ether groups.

30. The multipolymer of claim 23, wherein said hydrophilic soft segment comprises a compound having the formula O(CH₂)_N, where N<

4.

31. The multipolymer of claim 23, wherein said hydrophilic soft segment comprises polyethylene oxide.

32. The multipolymer of claim 23, wherein said oxygen-permeable soft segment further comprises polydimethlysiloxane.

33. The multipolymer of claim 23, wherein said at least one fluorine-containing soft segment comprises a perfluorinated or partially fluorinated hydrocarbon.

34. The multipolymer of claim 23, wherein said at least one fluorine-containing soft segment comprises a perfluorinated or partially fluorinated polyalkylsiloxane.

35. The multipolymer of claim 23, further comprising surface modifying end groups.

36. The multipolymer of claim 35, wherein said surface modifying end groups comprise perfluorinated or partially fluorinated hydrocarbons.

37. The multipolymer of claim 35, wherein said surface modifying end groups comprise perfluorinated or partially fluorinated polyethers.

38. The multipolymer of claim 35, wherein said surface modifying end groups comprise perfluorinated or partially fluorinated polyalkylsiloxanes.

39. A biocompatible multipolymer, comprising:

about 25-35 wt %, of total multipolymer weight, of hard segments;

about 25 to 40 wt %, of total multipolymer weight, of a first polycarbonate;

about 15 to 25 wt %, of total multipolymer weight, of polyethylene oxide or a second polycarbonate; and

about 15 to 25 wt %, of total multipolymer weight, of silicone, fluorocarbon, or fluorinated polyether.

40. The multipolymer of claim 39, wherein said first polycarbonate and said second polycarbonate are the same polycarbonate.

41. A drug delivery apparatus, comprising:

an insertable portion that is insertable in an animal body, wherein at least part of the insertable portion comprises a drug reservoir comprised of a multipolymer, said multipolymer comprising

at least one hard segment;

about 55 to 90 wt % of soft segments, including about 5 to 25 wt %, of total soft segment weight, of an oxygen permeable soft segment, less than about 25 wt %, of total soft segment weight, of a hydrophilic soft segment, and about 50 to 90 wt %, of total soft segment weight, of a biostable, hydrophobic soft segment.