Volume meter testing device

• US 20030007893A1
• Filed: 06/20/2002
• Published: 01/09/2003
• Est. Priority Date: 07/09/2001
• Status: Active Grant

• Current Assignee: Ascensia Diabetes Care Holdings AG (PHC Holdings Corporation)
• Original Assignee: Bayer Healthcare LLC (Bayer AG)
• Inventors: Purcell, D. Glenn
• Granted Patent: US 7,776,608 B2
• Time in Patent Office: Days
• US Class Current: 422/58
• CPC Class Codes: B01L 2200/026 Fluid interfacing between devices or objects, e.g. connectors, inlet details
• CPC Class Codes: B01L 2300/0663 Whole sensors
• CPC Class Codes: B01L 2300/0681 Filter
• CPC Class Codes: B01L 2300/069 Absorbents; Gels to retain a fluid
• CPC Class Codes: B01L 2300/0825 Test strips
• CPC Class Codes: B01L 2400/0406 capillary forces
• CPC Class Codes: B01L 3/5027 by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip B01L3/5023 takes precedence; micromixers B01F33/30; microreactors for synthesis B01J19/0093; microcapillary devices in general B81B1/00
• CPC Class Codes: G01N 27/3272 Test elements therefor, i.e. disposable laminated substrates with electrodes, reagent and channels optical biosensors G01N33/52

Abstract

A test device adapted to test a concentration of an analyte in a fluid has a pickup area having a first volume for receiving the fluid. In fluid communication with the pickup area is a read area having a second volume, which is less than the first volume. Since the second volume is less than the first volume, fluid from the pickup area will flow into the read area only after the pickup area is full. The read area also contains a reagent that is adapted to indicate the concentration of the analyte in the fluid.

Claims

1. A test device adapted to test a concentration of an analyte in a fluid comprising:

a pickup area having a first volume for receiving the fluid; and

a read area in fluid communication with the pickup area and having a second volume less than the first volume, such that the read area is adapted to receive fluid from the pickup area only after the pickup area is full, the read area containing a reagent adapted to produce a reaction indicative of the concentration of the analyte in the fluid.

2. The test device according to claim 1, wherein the pickup area comprises a first sidewall and a second sidewall independent of a floor or a ceiling.

3. The test device according to claim 1, wherein the read area comprises a ceiling and a floor.

4. The test device according to claim 3, wherein the ceiling of the read area is a plastic film.

5. The test device according to claim 3, wherein the ceiling of the read area is a porous paper.

6. The test device according to claim 5, wherein the floor of the read area is a filter.

7. The test device according to claim 5, wherein the ceiling of the read area includes at least one support, adapted to hold the ceiling a predetermined distance from the floor.

8. The test device according to claim 1, further comprising a transfer area in fluid communication with the read area and the pickup area, adapted to transfer the fluid from the pickup area into the read area.

9. The test device according to claim 8, wherein the transfer area has a third volume which is less than the first volume of the pickup area and larger than the second volume of the read area.

10. The test device according to claim 9, wherein the transfer area has sidewalls which are thinner than a sidewall of the pickup area.

11. The test device according to claim 8, wherein each of the pickup area, the transfer area, and the read area have capillary gaps to draw the fluid into the pickup area, the transfer area, and the read area.

12. The test device according to claim 11, wherein the capillary gap of the pickup area is larger than the capillary gap of the transfer area.

13. The test device according to claim 11, wherein the capillary gap of the transfer area is larger than the capillary gap of the read area.

14. The test device according to claim 1, wherein the second volume is in the range of about 70 to about 80 percent as large as the first volume.

15. The test device according to claim 14, wherein the second volume is in the range of about 3.5 to about 4.0 microliters and the first volume is in the range of about 4.5 to about 5.5 microliters.

16. The test device according to claim 1, wherein the reagent is adapted to produce a colorimetric reaction.

17. The test device according to claim 16, in combination with a calorimetric sensor.

18. The test device according to claim 1, wherein the reagent is adapted to produce an electrochemical reaction.

19. The test device according to claim 18, in combination with an electrochemical sensor.

20. The test device according to claim 1, wherein the analyte is glucose.

21. The test device according to claim 20, in combination with a sensor adapted to measure the concentration of glucose in blood.

32. The test device according to claim 5, wherein the ceiling of the read area includes at least one support, adapted to hold the ceiling a predetermined distance from the floor.

22. A test device adapted to test a concentration of an analyte in a fluid, comprising:

a pickup area having a first capillary gap adapted to use capillary action to draw the fluid into the pickup area; and

a read area in fluid communication with the pickup area and having a second capillary gap which is smaller than the first capillary gap of the pickup area, such that the fluid is drawn into the second capillary gap of the read area only after the first capillary gap of the pickup area is entirely filled.

23. The test device according to claim 22, wherein the pickup area comprises a first sidewall and a second sidewall independent of a floor or a ceiling.

24. The test device according to claim 22, wherein the pickup area has a first volume and the read area has a second volume, such that the first volume of the pickup area is greater than the second volume of the read area.

25. The test device according to claim 24, wherein the read area volume is from about 70 to about 80 percent as large as the pickup area volume.

26. The test device according to claim 24, wherein the read area volume is from about 3.5 to about 4.0 microliters and the pickup area volume is from about 4.5 to about 5.5 microliters.

27. The test device according to claim 22, further comprising a transfer area in fluid communication with the read area and the pickup area, adapted to transfer the analyte from the pickup area into the read area.

28. The test device according to claim 27, wherein the pickup area has a first volume, the read area has a second volume, and a transfer area has a third volume, the third volume being less than the first volume of the pickup area and larger than the second volume of the read area.

29. The test device according to claim 22, wherein the read area comprises a top and a bottom independent of any sidewalls.

30. The test device according to claim 29, wherein the bottom of the read area is a porous paper.

31. The test device according to claim 30, wherein the top of the read area is a filter.

33. The test device according to claim 22, wherein the reagent is adapted to produce a colorimetric reaction.

34. The test device according to claim 33, in combination with a colorimetric sensor.

35. The test device according to claim 22, wherein the reagent is adapted to produce an electrochemical reaction.

36. The test device according to claim 35, in combination with an electrochemical sensor.

37. The test device according to claim 22, wherein the analyte is glucose.

38. The test device according to claim 37, in combination with a sensor adapted to measure the concentration of glucose in a substance.

39. A blood chemical monitoring system for monitoring the concentration of an analyte in a fluid, comprising:

a pickup nib having a capillary gap adapted to use capillary action to draw the fluid into the pickup area, wherein the pickup nib further comprises a first sidewall and a second sidewall independent of a top side and a bottom side;

a read island adapted to draw the fluid from the pickup nib and having a capillary gap which is smaller than the capillary gap of the pickup area, such that the fluid is drawn into the capillary gap of the read area after the capillary gap of the pickup nib is entirely filled, wherein the read island further comprises a floor and a ceiling independent of any sidewalls, so as to prevent the formation of air gaps; and

a sensor for determining the concentration of the analyte in the fluid.

40. A method for determining a concentration of an analyte in a fluid with a test device, the test device comprising a pickup area and a read area in fluid communication with the pickup area, the method comprising:

drawing the fluid into the pickup area;

filling the pickup area with the fluid; and

drawing the fluid into the read area after the pickup area is substantially full of the fluid.

41. The method according to claim 40, further comprising mixing the fluid in the read area with a reagent disposed in the read area to produce a reaction.

42. The method according to claim 41, wherein the reaction is a colorimetric reaction.

43. The method according to claim 40, further comprising producing a signal indicative of the concentration of the analyte in the fluid.

44. The method according to claim 43, wherein the signal is a change in color.

45. The method according to claim 40, further comprising drawing the fluid into a transfer area after filling the fluid into the pickup area and prior to drawing the fluid into the read area.

46. The method according to claim 45, further comprising filling the transfer area with fluid prior to drawing the fluid into the read area.

47. The method according to claim 46, wherein filling the transfer area with fluid comprises using capillary action.

48. The method according to claim 40, wherein filling the read area with fluid comprises using capillary action.

49. The method according to claim 40, wherein filling the pickup area with the fluid comprises using capillary action.

50. The method according to claim 40, further comprising retaining fluid in the read area such that the likelihood of contamination of read instruments is reduced.

51. The method according to claim 40, wherein the analyte is glucose and the fluid is blood.

52. The method according to claim 40, further comprising using a sensor to read the concentration of the analyte in the fluid.

53. A test device adapted to test a concentration of an analyte in a fluid, comprising:

a pickup area having a first volume for receiving the fluid and a first capillary gap adapted to use capillary action to draw the fluid into the pickup area; and

a read area in fluid communication with the pickup area and having a second volume less than the first volume, such that the read area is adapted to receive fluid from the pickup area only after the pickup area is full, the read area further having a second capillary gap which is smaller than the first capillary gap, such that the fluid is drawn into the second capillary gap after the first capillary gap is entirely filled, the read area containing a reagent adapted to produce a reaction indicative of the concentration of the analyte in the fluid.