Glucose sensor and glucose level measuring apparatus

• US 8,277,636 B2
• Filed: 02/17/2009
• Issued: 10/02/2012
• Est. Priority Date: 09/02/2003
• Status: Active Grant

• Current Assignee: Koji Sode
• Original Assignee: Koji Sode
• Inventors: Sode, Koji
• Primary Examiner(s): GITOMER, RALPH J
• Application Number:
  US12/372,281
• Publication Number:
  US 20090177067A1
• Time in Patent Office: 1,323 Days
• Field of Search: 205/777.5, 204/403.14, 435/14, 435/26
• US Class Current: 205/777.5
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• 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 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/150229 Pumps for assisting the blood sampling
• CPC Class Codes: A61B 5/150358 Strips for collecting blood, e.g. absorbent optical reagent test strips G01N21/8483; chemical reagent test strips G01N33/4875, G01N33/52
• CPC Class Codes: A61B 5/150389 Hollow piercing elements, e.g. canulas, needles, for piercing the skin
• CPC Class Codes: A61B 5/150969 Low-profile devices which resemble patches or plasters, e.g. also allowing collection of blood samples for testing
• CPC Class Codes: A61B 5/150977 Arrays of piercing elements for simultaneous piercing
• CPC Class Codes: A61B 5/15105 Purely manual piercing, i.e. the user pierces the skin without the assistance of any driving means or driving devices
• CPC Class Codes: A61B 5/15186 Devices loaded with a single lancet, i.e. a single lancet with or without a casing is loaded into a reusable drive device and then discarded after use; drive devices reloadable for multiple use
• CPC Class Codes: A61B 5/155 Devices specially adapted for continuous or multiple sampling, e.g. at predetermined intervals devices loaded with multiple lancets simultaneously A61B5/15146
• CPC Class Codes: A61B 5/157 Devices characterised by integrated means for measuring characteristics of blood
• CPC Class Codes: A61B 5/681 Wristwatch-type devices
• CPC Class Codes: A61B 5/6849 in combination with a needle set
• CPC Class Codes: C12Q 1/006 for glucose

Abstract

The present invention relates to a glucose sensor (2) including an electrode (32) which includes a conductive component and glucose dehydrogenase immobilized to the conductive component. As the glucose dehydrogenase, use is made of a protein complex including a catalytic activity subunit which has glucose dehydrogenase activity, and an electron mediator subunit for supplying an electron donated from the catalytic activity subunit to the conductive component. Preferably, the glucose sensor (2) is designed to continuously measure the glucose level or successively measure the glucose level a plurality of times.

Claims

1. A glucose sensor adapted to be affixed to the skin of a subject, said sensor comprising an electrode and a sampler located outside the skin for sampling interstitial fluid underneath said skin,

wherein the electrode comprises an immobilized glucose dehydrogenase,

wherein the glucose dehydrogenase comprises a catalytic subunit and an electron mediator subunit, and the glucose dehydrogenase is derived from a microorganism belonging to the genus Burkholderia KS1 or a functional derivative thereof, and

wherein the sampler comprises a liquid reservoir in fluid communication with the interstitial fluid.

2. The glucose sensor according to claim 1, wherein the electron mediator subunit comprises a cytochrome c.

3. The glucose sensor of claim 1, wherein the glucose sensor is adapted to continuously determine a glucose concentration or successively determine a glucose concentration for at least 72 hours.

4. The glucose sensor of claim 1, wherein the liquid reservoir is in fluid communication with the interstitial fluid via a hollow lancing needle.

5. The glucose sensor of claim 1, wherein the electrode is provided on a flexible insulating substrate.

6. The glucose sensor of claim 1, further comprising a band or an adhesive tape.

7. The glucose sensor of claim 1, further comprising a counter electrode.

8. The glucose sensor of claim 1, wherein the immobilized glucose dehydrogenase is immobilized by chemical crosslinking.

9. The glucose sensor of claim 8, wherein the immobilized glucose dehydrogenase is immobilized using glutaraldehyde.

10. The glucose sensor of claim 1, wherein a flavin adenine dinucleotide (FAD) is bound to the catalytic subunit.

11. A glucose sensor adapted to be in contact with the skin of a subject, said sensor comprising a sampler located outside the skin for sampling fluid underneath said skin, and an electrode comprising a conductive component,

wherein the conductive component comprises an immobilized glucose dehydrogenase,

wherein the glucose dehydrogenase comprises a catalytic subunit and an electron mediator subunit, and the glucose dehydrogenase is derived from a microorganism belonging to the genus Burkholderia KS1 or a functional derivative thereof, and

wherein the sampler comprises a hollow lancing needle and a liquid reservoir.

12. The glucose sensor according to claim 11, wherein the electron mediator subunit is a cytochrome c.

13. The glucose sensor of claim 11, wherein the glucose sensor is adapted to continuously determine a glucose concentration or successively determine a glucose concentration for at least 72 hours.

14. The glucose sensor of claim 11, wherein the liquid reservoir is in fluid communication with the lancing needle.

15. The glucose sensor of claim 11, wherein the electrode is provided on a flexible insulating substrate.

16. The glucose sensor of claim 11, further comprising a band or an adhesive tape.

17. The glucose sensor of claim 11, further comprising a counter electrode.

18. The glucose sensor of claim 11, wherein the immobilized glucose dehydrogenase is immobilized by chemical crosslinking.

19. The glucose sensor of claim 18, wherein the immobilized glucose dehydrogenase is immobilized using glutaraldehyde.

20. The glucose sensor of claim 11, wherein a flavin adenine dinucleotide (FAD) is bound to the catalytic subunit.

21. A glucose monitoring apparatus for continuously determining a glucose concentration or determining a glucose concentration a plurality of times in blood or interstitial fluid comprising:

a glucose sensor adapted to be in contact with the skin of a subject comprising an electrode and a sampler located outside the skin for sampling interstitial fluid underneath said skin,

wherein the electrode comprises an immobilized glucose dehydrogenase, which is derived from a microorganism belonging to the genus Burkholderia KS1 or a functional derivative thereof, and

wherein the immobilized glucose dehydrogenase comprises

a catalytic subunit and an electron mediator subunit,

a measurer,

a computation unit, and

a controller,

wherein the sampler comprises a hollow lancing needle in fluid communication with a liquid reservoir.

22. The glucose monitoring apparatus of claim 21, wherein the electron mediator subunit is a cytochrome c.

23. The glucose monitoring apparatus of claim 21, adapted to continuously determine a glucose concentration or successively determine a glucose concentration for at least 72 hours.

24. The glucose monitoring apparatus of claim 21, wherein the electrode is provided on a flexible insulating substrate.

25. The glucose monitoring apparatus of claim 21, further comprising a band or an adhesive tape.

26. The glucose monitoring apparatus of claim 21, wherein the glucose sensor further comprises a counter electrode.

27. The glucose monitoring apparatus of claim 21, wherein the immobilized glucose dehydrogenase is immobilized by chemical crosslinking.

28. The glucose monitoring apparatus of claim 21, wherein the immobilized glucose dehydrogenase is immobilized using glutaraldehyde.

29. The glucose monitoring apparatus of claim 21, wherein a flavin adenine dinucleotide (FAD) is bound to the catalytic subunit.

30. The glucose monitoring apparatus of claim 21, further comprising a voltage application unit.

31. The glucose monitoring apparatus of claim 21, further comprising a display.

32. The glucose monitoring apparatus of claim 21, wherein the glucose sensor is disposable.