Analyte sensor

• US 20070045902A1
• Filed: 05/23/2006
• Published: 03/01/2007
• Est. Priority Date: 07/13/2004
• Status: Abandoned Application

• Current Assignee: DexCom Incorporated
• Original Assignee: DexCom Incorporated
• Inventors: Boock, Robert, Brister, Mark, Brauker, James, Simpson, Peter, Rixman, Monica
• Application Number:
  US11/439,800
• Publication Number:
  US 20070045902A1
• Time in Patent Office: Days
• US Class Current: 264/405
• CPC Class Codes: A61B 2562/08 Sensors provided with means for identification, e.g. barcodes or memory chips
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1473 invasive, e.g. introduced into the body by a catheter A61B5/1482 takes precedence
• CPC Class Codes: A61B 5/14865 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors
• CPC Class Codes: A61B 5/411 Detecting or monitoring allergy or intolerance reactions to an allergenic agent or substance
• CPC Class Codes: A61B 5/418 lymph vessels, ducts or nodes
• CPC Class Codes: A61B 5/6848 Needles
• CPC Class Codes: C12Q 1/006 for glucose
• CPC Class Codes: G01N 33/54366 Apparatus specially adapted for solid-phase testing
• CPC Class Codes: G01N 33/66 involving blood sugars, e.g. galactose
• CPC Class Codes: Y02A 50/30 Against vector-borne diseases, e.g. mosquito-borne, fly-borne, tick-borne or waterborne diseases whose impact is exacerbated by climate change

Abstract

The present invention relates generally to biointerface membranes utilized with implantable devices, such as devices for the detection of analyte concentrations in a biological sample. More particularly, the invention relates to novel biointerface membranes, to devices and implantable devices including these membranes, methods for forming the biointerface membranes on or around the implantable devices, and to methods for monitoring glucose levels in a biological fluid sample using an implantable analyte detection device.

Claims

1. A method for fabricating an analyte sensor configured for insertion into a host'"'"'s soft tissue, the method comprising:

forming a biointerface having a plurality of passageways and a solid portion on at least a sensing portion of a sensor, wherein the sensor is configured to measure an analyte in the host, and wherein the sensor has an architecture with at least one dimension less than about 1 mm.

2. The method of claim 2, wherein the step of forming a biointerface comprises a method selected from the group consisting of electrospinning, writing, lyophilizing, wrapping, weaving, and molding.

3. The method of claim 2, wherein the step of forming a biointerface comprises electrospinning the biointerface onto the sensor, writing the biointerface onto the sensor, lyophilizing the biointerface onto the sensor, wrapping the biointerface onto the sensor, weaving the biointerface onto the sensor, and molding the biointerface onto the sensor.

4. The method of claim 2, wherein the step of forming a biointerface comprises forming the biointerface directly on the sensor.

5. The method of claim 2, wherein the step of forming a biointerface comprises pre-forming the biointerface and then applying the preformed biointerface to the sensor.

6. The method of claim 2, wherein the step of forming a biointerface comprises pre-forming the biointerface and inserting the sensor into the preformed biointerface.

7. The method of claim 2, wherein the step of forming a biointerface comprises:

forming a selectively removable porogen on the sensor, wherein the porogen comprises particles formed onto the sensor and solidified to form a solidified mass of continuously interconnected particles;

filling the porogen with a material;

substantially solidifying the material; and

removing the mass of continuously interconnected particles from contact with the sensor and solidified material to thereby form a solid portion that defines a plurality of passageways of the biointerface.

8. The method of claim 2, wherein the biointerface comprises a material selected from the group consisting of silicone, polytetrafluoroethylene, expanded polytetrafluoroethylene, polyethylene-co-tetrafluoroethylene, polyolefin, polyester, polycarbonate, biostable polytetrafluoroethylene, polyurethane homopolymer, polyurethane copolymer, polyurethane terpolymer, polypropylene, polyvinylchloride, polyvinylidene fluoride, polyvinyl alcohol, polybutylene terephthalate, polymethylmethacrylate, polyether ether ketone, polyamide, polyurethane, cellulosic polymer, poly(ethylene oxide), poly(propylene oxide), poly(propylene oxide) copolymer, polysulfone, polysulfone, block copolymers thereof, di-block copolymers thereof, tri-block copolymers thereof, alternating copolymers thereof, random copolymers thereof, graft copolymers thereof, mixtures thereof, and blends thereof.

9. The method of claim 2, wherein the step of forming a biointerface comprises forming an amorphous biointerface.

10. The method of claim 2, wherein the biointerface comprises pores of at least about 20 microns.

11. The method of claim 2, wherein the step of forming a biointerface comprises forming a fibrous biointerface.

12. The method of claim 11, wherein the biointerface comprises fibers less than about 6 microns in all but the longest dimension.

13. The method of claim 2, further comprising a step of incorporating a bioactive agent into the biointerface.

14. The method of claim 13, wherein the bioactive agent is selected from the group consisting of an anti-barrier cell agent, an anti-inflammatory agent, an anti-infective agent, a necrosing agent, an anesthetic, an inflammatory agent, a growth factor, an angiogenic factor, an adjuvant, an immunosuppressive agent, an antiplatelet agent, an anticoagulant, an ACE inhibitor, a cytotoxic agent, a vascularization compound, and an anti-sense molecule.

15. The method of claim 2, wherein the step of forming a biointerface comprises writing a biointerface onto the sensor using a computer-aided machine.

16. A method for fabricating an analyte sensor configured to be wholly implanted in a host'"'"'s soft tissue, the method comprising:

providing a sensor configured to measure an analyte in the host, wherein the sensor has an architecture with at least one dimension less than about 1 mm; and

coating a biointerface onto the sensor, the biointerface comprising a plurality of cavities and a solid portion.

17. The method of claim 16, wherein the cavities are interconnected.

18. The method of claim 16, wherein the coating step comprises a method selected from the group consisting of electrospinning, writing, lyophilizing, wrapping, weaving, and molding.

19. The method of claim 16, further comprising a step of curing the biointerface.

20. The method of claim 16, wherein the coating step comprises:

forming a selectively removable porogen onto the sensor, wherein the porogen comprises particles formed onto the sensor and solidified to form a solidified mass of continuously interconnected particles;

filling the porogen with a material;

substantially solidifying the material; and

removing the mass of continuously interconnected particles from contact with the sensor and solidified material to thereby form a solid portion that defines a plurality of passageways of the biointerface.

21. The method of claim 16, wherein the biointerface comprises a material selected from the group consisting of silicone, polytetrafluoroethylene, expanded polytetrafluoroethylene, polyethylene-co-tetrafluoroethylene, polyolefin, polyester, polycarbonate, biostable polytetrafluoroethylene, polyurethane homopolymer, polyurethane copolymer, polyurethane terpolymer, polypropylene, polyvinylchloride, polyvinylidene fluoride, polyvinyl alcohol, polybutylene terephthalate, polymethylmethacrylate, polyether ether ketone, polyamide, polyurethane, cellulosic polymer, poly(ethylene oxide), poly(propylene oxide), poly(propylene oxide) copolymer, polysulfone, polysulfone, block copolymers thereof, di-block copolymers thereof, tri-block copolymers thereof, alternating copolymers thereof, random copolymers thereof, graft copolymers thereof, mixtures thereof, and blends thereof.

22. The method of claim 16, wherein the biointerface is an amorphous biointerface.

23. The method of claim 22, wherein the amorphous biointerface is molded onto the sensor.

24. The method of claim 16, wherein the coating step comprises forming a fibrous biointerface.

25. The method of claim 24, wherein the biointerface comprises fibers less than about 6 microns in all but the longest dimension.

26. The method of claim 16, further comprising a step of incorporating a bioactive agent into the biointerface.

27. The method of claim 26, wherein the bioactive agent is selected from the group consisting of an anti-barrier cell agent, an anti-inflammatory agent, an anti-infective agent, a necrosing agent, an anesthetic, an inflammatory agent, a growth factor, an angiogenic factor, an adjuvant, a wound factor, an immunosuppressive agent, an antiplatelet agent, an anticoagulant, an ACE inhibitor, a cytotoxic agent, a vascularization compound, and an anti-sense molecule.

28. The method of claim 16, wherein the coating step comprises writing a biointerface onto the sensor using a computer-aided machine.

29. The method of claim 16, further comprising a step of curing the biointerface.

30. A method for making an analyte sensor configured for insertion into a host'"'"'s soft tissue, the method comprising:

providing a sensor configured to measure an analyte in a host, wherein the sensor has an architecture with at least one dimension less than about 1 mm; and

directly writing a porous biointerface, wherein the porous biointerface is written based on a predefined pattern stored in a computer system.

31. The method of claim 30, further comprising a step of curing the biointerface during direct writing step or after the direct writing step.

32. The method of claim 30, wherein the porous biointerface is directly written onto the sensor.

33. The method of claim 30, wherein the porous biointerface is directly written onto a substrate and then applied to the sensor.