Method and device for sampling and analyzing interstitial fluid and whole blood samples

• US 20040236250A1
• Filed: 02/13/2003
• Published: 11/25/2004
• Est. Priority Date: 03/27/2000
• Status: Abandoned Application

• Current Assignee: Alastair Hodges, Garry Chambers, Ron Chatelier
• Original Assignee: Alastair Hodges, Garry Chambers, Ron Chatelier
• Inventors: Hodges, Alastair, Chambers, Garry, Chatelier, Ron
• Application Number:
  US10/369,120
• Publication Number:
  US 20040236250A1
• Time in Patent Office: Days
• US Class Current: 600/583
• CPC Class Codes: A61B 2010/008 Interstitial fluid
• CPC Class Codes: A61B 2562/0295 Strip shaped analyte sensors for apparatus classified in A61B5/145 or A61B5/157 disposable multilayered or laminated electrodes G01N27/307; details of handling chemical test elements G01N33/4875
• CPC Class Codes: A61B 5/14514 using means for aiding extraction of interstitial fluid, e.g. microneedles or suction
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• 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 5/150213 Venting means
• CPC Class Codes: A61B 5/150221 Valves
• 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 5/150503 Single-ended needles hollow piercing element tip design A61B5/150396, needle sets for catheters A61M25/06, needles for bringing media into the body A61M5/32
• CPC Class Codes: A61B 5/150755 Blood sample preparation for further analysis, e.g. by separating blood components or by mixing
• 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 5/15113 Manually triggered, i.e. the triggering requires a deliberate action by the user such as pressing a drive button
• CPC Class Codes: A61B 5/15117 comprising biased elements, resilient elements or a spring, e.g. a helical spring, leaf spring, or elastic strap
• CPC Class Codes: A61B 5/15142 Devices intended for single use, i.e. disposable
• CPC Class Codes: A61B 5/1519 comprising driving means, e.g. a spring, for propelling the piercing unit

Abstract

The invention disclosed in this application is a method and device for combining the sampling and analyzing of sub-dermal fluid samples, e.g., interstitial fluid or whole blood, in a device suitable for hospital bedside and home use. It is applicable to any analyte that exists in a usefully representative concentration in the fluid, and is especially suited to the monitoring of glucose.

Claims

1. A fluid sampling device, the device comprising a body, the body comprising:

a dermal layer penetration probe having a penetrating end and a communicating end, the penetration probe having a volume; and

an analysis chamber having a proximal end and a distal end, the analysis chamber having a volume, wherein the volume of the penetration probe is greater than the volume of the analysis chamber, and wherein the penetration probe is in fluid communication with the analysis chamber such that fluid can flow from the penetration probe to the analysis chamber.

2. The device of claim 1, wherein the penetration probe is capable of exerting a first capillary force and the analysis chamber is capable of exerting a second capillary force, and wherein a differential in capillary force exists between the first capillary force and the second capillary force.

3. The device of claim 2, wherein the second capillary force is greater than the first capillary force.

4. The device of claim 3, wherein an interior surface of the penetration probe comprises a first penetration probe wall and a second penetration probe wall, wherein the first penetration probe wall and the second penetration probe wall are spaced apart at a first distance to define a penetration probe height, and wherein an interior surface of the analysis chamber comprises a first analysis chamber wall and a second analysis chamber wall, wherein the first analysis chamber wall and the second analysis chamber wall are spaced apart at a second distance to define an analysis chamber height, wherein the analysis chamber height is less than the penetration probe height, and wherein the differential in capillary force derives at least in part from a difference between the penetration probe height and the analysis chamber height.

5. The device of claim 3, wherein at least one of the penetration probe and the analysis chamber comprises a substance capable of enhancing or diminishing a capillary force.

6. The device of claim 5, wherein the substance is selected from the group consisting of a polymer, a resin, a powder, a mesh, a fibrous material, a crystalline material, a porous material, and a combination thereof.

7. The device of claim 6, wherein the substance is selected from the group consisting of polyethylene glycol, polyvinylpyrrolidone, a surfactant, a hydrophilic block copolymer, and polyvinylacetate.

8. The device of claim 1, wherein the penetration probe comprises a first penetration probe wall and a second penetration probe wall and wherein the analysis chamber comprises a first analysis chamber wall and a second analysis chamber wall, and wherein the distance between the first penetration probe wall and the second penetration probe wall is greater than the distance between the first analysis chamber wall and the second analysis chamber wall.

9. The device of claim 1, wherein the penetration probe comprises a component selected from the group consisting of a needle, a lancet, a tube, a channel, and a solid protrusion.

10. The device of claim 1, wherein the device has a proximal edge, the proximal edge comprising a recess, wherein the penetration probe is positioned within the recess.

11. The device of claim 10, wherein the recess is configured to substantially align with a shape of a selected dermal surface.

12. The device of claim 1, further comprising a releasable actuator, wherein the actuator is capable of supplying a force sufficient to cause the penetration probe to penetrate a dermal layer.

13. The device of claim 12, wherein the actuator is external to the body, and wherein upon release the actuator propels the body to the dermal layer.

14. The device of claim 12, wherein the actuator is integral with the body.

15. The device of claim 14, wherein upon release the actuator propels the penetration probe toward the dermal layer.

16. The device of claim 1, wherein the analysis chamber comprises an electrochemical cell, the cell comprising a working electrode and a counter/reference electrode.

17. The device of claim 1, further comprising an interface for communication with a meter.

18. The device of claim 17, wherein the interface communicates a voltage or a current.

19. The device of claim 1, wherein the analysis chamber comprises a hollow electrochemical cell, the hollow electrochemical cell comprising a working electrode, a counter or reference electrode, and an opening for admitting an analyte to the cell, the working electrode being spaced from the counter or reference electrode by a distance of less than 500 μ

m.

20. The device of claim 19, wherein the penetration probe comprises a component selected from the group consisting of a needle, a lancet, a tube, a channel, and a solid protrusion.

21. The device of claim 19, wherein the penetration probe is capable of exerting a first capillary force and the analysis chamber is capable of exerting a second capillary force and wherein a differential exists between the first capillary force and the second capillary force.

22. The device of claim 21, wherein the second capillary force is greater than the first capillary force.

23. The device of claim 1, wherein a distal end of the penetration probe is interfaced with the proximal end of the analysis chamber.

24. The device of claim 1, wherein a distal end of the penetration probe is integrated with the proximal end of the analysis chamber.

25. A fluid sampling device comprising a body, the body comprising

a dermal layer penetration probe having a penetrating end and a communicating end;

an analysis chamber having a proximal end and a distal end, the analysis chamber having a volume, wherein the analysis chamber comprises a hollow electrochemical cell, the hollow electrochemical cell comprising a working electrode, a counter or reference electrode, and an opening for admitting an analyte to the cell, the working electrode being spaced from the counter or reference electrode by a distance of less than 500 μ

m; and

a pre-chamber having a proximal end and a distal end, the pre-chamber having a volume, wherein the pre-chamber is interposed between the penetration probe and the analysis chamber such that the proximal end of the pre-chamber is adjacent the communicating end of the penetration probe and the distal end of the pre-chamber is adjacent the proximal end of the analysis chamber, wherein the volume of the pre-chamber is greater than the volume of the analysis chamber, and wherein the penetration probe is in fluid communication with the analysis chamber such that fluid can flow from the penetration probe to the analysis chamber.

26. The device of claim 25, wherein the penetration probe comprises a component selected from the group consisting of a needle, a lancet, a tube, a channel, and a solid protrusion.

27. The device of claim 25, wherein the pre-chamber is capable of exerting a first capillary force and the analysis chamber is capable of exerting a second capillary force and wherein a differential in capillary force exists between the first capillary force and the second capillary force.

28. The device of claim 27, wherein the second capillary force is greater than the first capillary force.

29. The device of claim 25, wherein the distal end of the pre-chamber is interfaced with the proximal end of the analysis chamber.

30. The device of claim 25, wherein the distal end of the pre-chamber is integrated with the proximal end of the analysis chamber.

31. A method for measuring a quantity of an analyte in a fluid sample, the method comprising the steps of:

providing a fluid sampling device, the sampling device comprising;

a dermal layer penetration probe, having a penetrating end and a communicating end;

an analysis chamber having a proximal end and a distal end, the analysis chamber having a volume, wherein the penetration probe is in fluid communication with the analysis chamber such that a fluid sample can flow from the penetration probe to the analysis chamber; and

a pre-chamber having a proximal end and a distal end, the pre-chamber having a volume, wherein the pre-chamber is interposed between the penetration probe and the analysis chamber such that the proximal end of the pre-chamber is adjacent the communicating end of the penetration probe and the distal end of the pre-chamber is adjacent the proximal end of the analysis chamber, and wherein the volume of the pre-chamber is greater than the volume of the analysis chamber;

penetrating a dermal layer with the penetration probe;

substantially filling the analysis chamber with the fluid sample by allowing the sample to flow from the penetration probe to the analysis chamber; and

measuring a quantity of an analyte in the fluid sample.

32. The method of claim 31, wherein the sample is selected from the group consisting of interstitial fluid and whole blood.

33. The method of claim 31, wherein the analyte is selected from the group consisting of an ion, an element, a sugar, an alcohol, a hormone, a protein, an enzyme, a cofactor, a nucleic acid sequence, a lipid, a pharmaceutical, and a drug.

34. The method of claim 31, wherein the analyte is selected from the group consisting of potassium ion, ethanol, cholesterol, glucose, and lactate.

35. The method of claim 31, wherein a flow of fluid sample to the analysis chamber is driven by a driving force, wherein the driving force comprises a force selected from the group consisting of a capillary force and a pressure differential.

36. The method of claim 31, wherein the pre-chamber is capable of exerting a first capillary force and the analysis chamber is capable of exerting a second capillary force and wherein a differential in capillary force exists between the first capillary force and the second capillary force.

37. The method of claim 31, wherein the second capillary force is greater than the first capillary force.

38. The method of claim 31, wherein an interior surface of the pre-chamber comprises a first pre-chamber wall and a second pre-chamber wall, wherein the first pre-chamber wall and the second pre-chamber wall are spaced apart at a first distance to define a pre-chamber height, and wherein an interior surface of the analysis chamber comprises a first analysis chamber wall and a second analysis chamber wall spaced apart at a second distance to define an analysis chamber height, wherein the analysis chamber height is less than the pre-chamber height, wherein the pre-chamber is capable of exerting a first capillary force and the analysis chamber is capable of exerting a second capillary force, and wherein a differential in the first capillary force and the second capillary force derives at least in part from a difference between the pre-chamber height and the analysis chamber height.

39. The method of claim 31, wherein at least one of the pre-chamber and the analysis chamber comprises a substance capable of enhancing or diminishing a capillary force.

40. The method of claim 39, wherein the substance is selected from the group consisting of a polymer, a resin, a powder, a mesh, a fibrous material, a crystalline material, a porous material, and a combination thereof.

41. The method of claim 39, wherein the substance is selected from the group consisting of polyethylene glycol, polyvinyl pyrrolidone, a surfactant, a hydrophilic block copolymer, and polyacrylic acid.

42. The method of claim 35, wherein the pressure differential comprises a positive pressure applied to the analysis chamber.

43. The method of claim 35, wherein the pressure differential comprises a negative pressure applied from the analysis chamber.

44. The method of claim 31, wherein the analysis chamber comprises a hollow electrochemical cell, the hollow electrochemical cell comprising a working electrode, a counter or reference electrode, and an opening for admitting an analyte to the cell, the working electrode being spaced from the counter or reference electrode by a distance of less than 500 μ

m.

45. The method of claim 44, wherein the penetration probe comprises a component selected from the group consisting of a needle, a lancet, a tube, a channel, and a solid protrusion.

46. The method of claim 44, wherein the pre-chamber is capable of exerting a first capillary force and the analysis chamber is capable of exerting a second capillary force and wherein a differential in capillary force exists between the first capillary force and the second capillary force.

47. The method of claim 44, wherein the second capillary force is greater than the first capillary force.

48. A method for measuring a quantity of an analyte in a fluid sample, the method comprising the steps of:

providing a fluid sampling device, the device comprising;

a dermal layer penetration probe having a penetrating end and a communicating end, the penetration probe having a volume;

an analysis chamber having a proximal and distal end, the analysis chamber having a volume, wherein the volume of the penetration probe is greater than the volume of the analysis chamber, wherein the penetration probe is in fluid communication with the analysis chamber such that a fluid sample can flow from the penetration probe to the analysis chamber;

penetrating a dermal layer with the penetration probe;

substantially filling the analysis chamber with a fluid sample by allowing the

sample to flow from the penetration probe to the analysis chamber; and

measuring a quantity of an analyte in the fluid sample.

49. The method of claim 48, wherein the sample is selected from the group consisting of interstitial fluid and whole blood.

50. The method of claim 48, wherein the analyte is selected from the group consisting of an ion, an element, a sugar, an alcohol, a hormone, a protein, an enzyme, a cofactor, a nucleic acid sequence, a lipid, a pharmaceutical, and a drug.

51. The method of claim 48, wherein the analyte is selected from the group consisting of potassium ion, ethanol, cholesterol, glucose, and lactate.

52. The method of claim 48, wherein a flow of sample to the analysis chamber is driven by a driving force, wherein the driving force comprises a force selected from the group consisting of a capillary force and a pressure differential.

53. The method of claim 48, wherein the penetration probe is capable of exerting a first capillary force and the analysis chamber is capable of exerting a second capillary force and wherein a differential in capillary force exists between the first capillary force and the second capillary force.

54. The method of claim 48, wherein the second capillary force is greater than the first capillary force.

55. The method of claim 48, wherein an interior surface of the penetration probe comprises a first penetration probe wall and a second penetration probe wall, wherein the first penetration probe wall and the second penetration probe wall are spaced apart at a first distance to define a penetration probe height, and wherein an interior surface of the analysis chamber comprises a first analysis chamber wall and a second analysis chamber wall, wherein the first analysis chamber wall and the second analysis chamber wall are spaced apart at a second distance to define an analysis chamber height, wherein the height of the analysis chamber is less than the height of the penetration probe, wherein the penetration probe is capable of exerting a first capillary force and the analysis chamber is capable of exerting a second capillary force and wherein a differential in capillary force exists between the first capillary force and the second capillary force, and wherein the differential capillary force derives at least in part from a difference between the penetration probe height and the analysis chamber height.

56. The method of claim 48, wherein at least one of the penetration probe and the analysis chamber comprises a substance capable of enhancing or diminishing a capillary force.

57. The method of claim 56, wherein the substance is selected from the group consisting of a polymer, a resin, a powder, a mesh, a fibrous material, a crystalline material, a porous material, and a combination thereof.

58. The method of claim 56, wherein the substance is selected from the group consisting of polyethylene glycol, polyvinyl pyrrolidone, a surfactant, a hydrophilic block copolymer, and polyacrylic acid.

59. The method of claim 52, wherein the pressure differential comprises a positive pressure applied to the analysis chamber.

60. The method of claim 52, wherein the pressure differential comprises a negative pressure applied from the analysis chamber.

61. The method of claim 48, wherein the analysis chamber comprises a hollow electrochemical cell, the hollow electrochemical cell comprising a working electrode, a counter or reference electrode, and an opening for admitting an analyte to the cell, the working electrode being spaced from the counter or reference electrode by a distance of less than 500 μ

m.

62. The method of claim 61, wherein the penetration probe comprises a component selected from the group consisting of a needle, a lancet, a tube, a channel, and a solid protrusion.

63. The method of claim 61, wherein the penetration probe is capable of exerting a first capillary force and the analysis chamber is capable of exerting a second capillary force and wherein a differential in capillary force exists between the first capillary force and the second capillary force.

64. The method of claim 61, wherein the second capillary force is greater than the first capillary force.