Analytical test device and method for use in medical diagnoses

• US 6,214,629 B1
• Filed: 07/14/1999
• Issued: 04/10/2001
• Est. Priority Date: 08/06/1998
• Status: Expired due to Term

• Current Assignee: Nexus Dx, Inc. (Sphingotec GMBH)
• Original Assignee: Spectral Diagnostics, Inc.
• Inventors: Shi, Oinwei, Freitag, Helmut E., Harrington, Charles A.
• Primary Examiner(s): Le, Long V.
• Assistant Examiner(s): PHAM, MINH QUAN K
• Application Number:
  US09/353,190
• Time in Patent Office: 636 Days
• Field of Search: 435/5, 435/7.1, 435/7.2, 435/7.24, 435/7.29, 435/7.92, 435/287.2, 435/288.2, 435/6, 435/91.2, 436/514, 436/516, 436/518, 436/164, 436/165, 436/69, 436/811, 436/815, 422/56, 422/57, 422/58, 422/61, 422/72, 422/82.06
• US Class Current: 436/518
• CPC Class Codes: G01N 2333/4712 Muscle proteins, e.g. myosin, actin, protein
• CPC Class Codes: G01N 2333/805 Haemoglobins; Myoglobins
• CPC Class Codes: G01N 2333/9123 with a nitrogenous group as acceptor (2.7.3), e.g. histidine kinases
• CPC Class Codes: G01N 33/54366 Apparatus specially adapted for solid-phase testing
• CPC Class Codes: G01N 33/54387 Immunochromatographic test strips
• CPC Class Codes: G01N 33/558 using diffusion or migration of antigen or antibody immunochromatographic test strips G01N33/54387
• CPC Class Codes: Y10S 436/811 Test for named disease, body condition or organ function
• CPC Class Codes: Y10S 436/815 Test for named compound or class of compounds

Abstract

An analytical test device is described for the immunochromatographic determination of the presence of one or more analytes in fluid samples. The device is configured such that the sample is allowed to enter the detection zone simultaneously from many different directions, eliminating stagnation of the flow of the sample. By selection of the porous substrate, the device also allows for the separation of red blood cells from plasma, providing a rapid test for one or more analytes in a sample of whole blood. The device of the present invention may measure more than one analyte simultaneously from a single sample, either by having multiple immunochromatographic pathways fed by a single sample, or multiple analytes detected in the same pathway by way of multiple capture antibodies.

Claims

1. An analytical test device suitable for determining the presence of at least one analyte contained in a liquid sample while permitting rapid and efficient flow of the sample through at least one defined pathway in which reactions determinative of the analyte take place, said device comprising:

a top layer having an upper surface formed with a through hole for the addition of the sample, said through hole being in registry with a sample delivery channel formed in the upper surface of the top layer, said sample delivery channel in operative communication with a sample circulation channel closed at its terminal ends and formed with inner and outer walls to define a pathway for the sample in the lower surface of the top layer, the inner walls of the circulation channel defining an indent in the lower surface of the top layer;

a bottom layer attached to the top layer, said bottom layer and top layer holding a dry porous carrier therebetween, said dry porous carrier having a fluid pathway;

said fluid pathway of said dry porous carrier layer configured to contain at least one detection zone having a border in operative communication with a segment of the sample circulation channel and an opposite end in operative communication with a capture zone channel having an entrance end and a closed terminal end thereby to provide a conduit through which the liquid sample may flow by capillary action from the sample circulation channel from a plurality of different directions onto the porous carrier and to the entrance of the capture zone channel, into the capture zone channel, to the terminal end of the capture zone channel;

the distances between all points where the sample is permitted to enter the detection zone and said entrance end being essentially the same; and

the delivery channel, circulation channel, detection zone and capture zone channel forming a defined pathway through which the liquid sample flows from the through hole to the terminal end of the capture channel;

there being immobilized reagent in the capture zone channel which will react with said analyte to form a detectable product.

2. The device of claim 1 further comprising at least one mobile, labelled reagent which will specifically react with the analyte to form a labelled complex which will move by capillary action into the capture zone channel;

and there being immobilized reagent in the capture zone channel which will react with and concentrate the labelled complex to form a detectable reaction product.

3. The device of claim 2 wherein the mobile reagent in the detection zone is a labelled antibody which will react with one epitope on the analyte and the immobilized reagent is an antibody which will react with another epitope on the analyte.

4. The device of claim 2 comprising a mixture of a mobile labelled antibody which will react with one epitope on the analyte and a mobile biotin labelled antibody which will react with another epitope on the analyte, and the immobilized reagent is an avidin.

5. The device of claim 2 wherein, the immobilized reagent is selected from the group consisting of streptavidin and avidin.

6. The device of claim 1 in which the sample circulation channel is arcuate.

7. The device of claim 1 in which the liquid sample is selected from the group consisting of whole blood, plasma, serum and urine.

8. The device of claim 1 wherein the analyte is selected from the group consisting of myoglobin, CK-MB either troponin I or troponin T, and combinations thereof.

9. The device of claim 1 wherein the analyte is selected from the group consisting of hCG, LH and mixtures thereof.

10. The device of claim 1 wherein the label is a particulate direct label.

11. The device of claim 1 wherein the label is a gold label.

12. The device of claim 11 wherein said border of said detection zone is polygonal or forms part of a polygon.

13. The device of claim 12 wherein said border of said detection zone is rectangular or forms part of a rectangle.

14. The device of claim 1 in which the dry porous carrier is nitrocellulose.

15. The device of claim 1 containing the reagents for determining the presence of troponin I or troponin T.

16. The device of claim 1 containing two pathways, one containing the reagents for determining the presence of myoglobin, the other containing the reagents for determining the presence of CK-MB.

17. The device of claim 1 containing three pathways, the one pathway containing the reagents for determining the presence of troponin I or troponin T, another pathway containing the reagents for determining the presence of myoglobin and still another pathway containing the reagents for determining the presence of CK-MB.

18. The device of claim 1 in which contains only the reagents for determining the presence of troponin I.

19. The device of claim 1 in which there is only one pathway and it contains the reagents for determining the presence of myoglobin and CK-MB.

20. The device of claim 1 in which there is only one pathway and it contains the reagents for determining the presence of troponin I or troponin T together with the reagents for determining the presence of myoglobin and CK-MB.

21. The device of claim 1 wherein said sample delivery channel has a predetermined capacity corresponding to the volume of sample needed to conduct said determining of said at least one analyte, said sample delivery channel having means for conducting said predetermined volume of sample from said sample delivery channel to said sample circulation channel when said sample delivery channel is filled with said predetermined volume.

22. The device of claim 19 wherein the portion of said sample delivery channel in operative communication with said sample circulation channel comprises a narrowed capillary portion leading to said sample circulation channel, wherein when the sample delivery channel is filled with said sample to the point of contact with said narrowed capillary portion, said sample is conducted to the sample circulation channel.

23. The device of claim 1 wherein a dried reagent is present in said sample delivery channel.

24. The device of claim 21 wherein said dried reagent is selected from the group consisting of a labeled antibody to said analyte, a biotinylated antibody to said analyte, and the combination thereof.

25. The device of claim 1 wherein said border of said detection zone is semicircular.

26. The device of claim 1 wherein said sample circulation channel is polygonal or forms part of a polygon.

27. The device of claim 24 wherein said sample circulation channel is rectangular or forms part of a rectangle.

28. An analytical test device suitable for determining the presence of at least one analyte contained in a liquid sample while permitting rapid and efficient flow of the sample through at least one defined pathway in which reactions determinative of the analyte take place, said device comprising:

a top layer having an upper surface formed with a through hole for the addition of the sample, said through hole being in registry with a sample delivery channel formed in the upper surface of the top layer, said sample delivery channel in operative communication with a sample circulation channel closed at its terminal ends and formed with inner and outer walls to define a pathway for the sample in the lower surface of the top layer, the inner walls of the circulation channel defining an indent in the lower surface of the top layer;

a bottom layer attached to the top layer, said bottom layer and top layer holding a dry porous carrier therebetween, said dry porous carrier having a fluid pathway;

said fluid pathway of said dry porous carrier layer configured to contain at least one detection zone having a border in operative communication with a segment of the sample circulation channel and an opposite end in operative communication with a capture zone channel having an entrance end and a closed terminal end thereby to provide a conduit through which the liquid sample may flow by capillary action from the sample circulation channel from a plurality of different directions onto the porous carrier and to the entrance of the capture zone channel, into the capture zone channel, to the terminal end of the capture zone channel; and

the delivery channel, circulation channel, detection zone and capture zone channel forming a defined pathway through which the liquid sample flows from the through hole to the terminal end of the capture channel;

there being immobilized reagent in the capture zone channel which will react with said analyte to form a detectable product.

29. The device of claim 28 wherein said sample circulation channel is polygonal or forms part of a polygon.

30. The device of claim 29 wherein said sample circulation channel is rectangular or forms part of a rectangle.

31. The device of claim 29 wherein said border of said detection zone is polygonal or forms pail of a polygon.

32. The device of claim 31 wherein said border of said detection zone is rectangular or forms part of a rectangle.

33. The device of claim 28 further comprising at least one mobile, labelled reagent which will specifically react with the analyte to form a labelled complex which will move by capillary action into the capture zone channel;

and there being immobilized reagent in the capture zone channel which will react with and concentrate the labelled complex to form a detectable reaction product.

34. The device of claim 33 comprising a mixture of a mobile labelled antibody which will react with one epitope on the analyte and a mobile biotin labelled antibody which will react with another epitope on the analyte, and the immobilized reagent is an avidin.

35. The device of claim 33 wherein, the immobilized reagent is selected from the group consisting of streptavidin and avidin.

36. The device of claim 28 in which the liquid sample is selected from the group consisting of whole blood, plasma, serum and urine.

37. The device of claim 28 wherein the analyte is selected from the group consisting of myoglobin, CK-MB either troponin I or troponin T, and combinations thereof.

38. The device of claim 28 wherein the analyte is selected from the group consisting of hCG, LH and mixtures thereof.

39. The device of claim 28 wherein the mobile reagent in the detection zone is a labelled antibody which will react with one epitope on the analyte and the immobilized reagent is an antibody which will react with another epitope on the analyte.

40. The device of claim 28 wherein the label is a particulate direct label.

41. The device of claim 28 wherein the label is a gold label.

42. The device of claim 28 in which the dry porous carrier is nitrocellulose.

43. The device of claim 28 containing the reagents for determining the presence of troponin I or troponin T.

44. The device of claim 28 containing two pathways, one containing the reagents for determining the presence of myoglobin, the other containing the reagents for determining the presence of CK-MB.

45. The device of claim 28 containing three pathways, the one pathway containing the reagents for determining the presence of troponin I or troponin T, another pathway containing the reagents for determining the presence of myoglobin and still another pathway containing the reagents for determining the presence of CK-MB.

46. The device of claim 28 in which contains only the reagents for determining the presence of troponin I.

47. The device of claim 28 in which there is only one pathway and it contains the reagents for determining the presence of myoglobin and CK-MB.

48. The device of claim 28 in which there is only one pathway and it contains the reagents for determining the presence of troponin I or troponin T together with the reagents for determining the presence of myoglobin and CK-MB.

49. The device of claim 28 wherein said sample delivery channel has a predetermined capacity corresponding to the volume of sample needed to conduct said determining of said at least one analyte, said sample delivery channel having means for conducting said predetermined volume of sample from said sample delivery channel to said sample circulation channel when said sample delivery channel is filled with said predetermined volume.

50. The device of claim 49 wherein the portion of said sample delivery channel in operative communication with said sample circulation channel comprises a narrowed capillary portion leading to said sample circulation channel, wherein when the sample delivery channel is filled with said sample to the point of contact with said narrowed capillary portion, said sample is conducted to the sample circulation channel.

51. The device of claim 28 wherein a dried reagent is present in said sample delivery channel.

52. The device of claim 51 wherein said dried reagent is selected from the group consisting of a labeled antibody to said analyte, a biotinylated antibody to said analyte, and the combination thereof.

53. A method for determining the presence of at least one analyte contained in a liquid sample comprising the steps of:

i) providing an analytical test device suitable for determining the presence of at least one analyte contained in a low volume of a liquid biological sample while permitting rapid and efficient flow of the sample through at least one defined pathway which reactions determinative of the analyte take place, said device comprising;

a) a top layer having an upper surface formed with a through hole for the addition of the sample, said through hole being in registry with a sample delivery channel formed in the upper surface of the top layer, said sample delivery channel in operative communication with a sample circulation channel closed at its terminal ends and formed with inner and outer walls to define a pathway for the sample in the lower surface of the top layer, the inner walls of the circulation channel defining an indent in the lower surface of the top layer;

b) a bottom layer attached to the top layer, said bottom layer and top layer holding a dry porous carrier therebetween, said dry porous carrier having a fluid pathway;

c) said fluid pathway of said dry porous carrier layer configured to contain at least one detection zone having a border in operative communication with a segment of the sample circulation channel and an opposite end in operative communication with a capture zone channel having an entrance end and a closed terminal end thereby to provide a conduit through which the liquid sample may flow by capillary action from the sample circulation channel from a plurality of different directions onto the porous carrier and to the entrance of the capture zone channel, into the capture zone channel, to the terminal end of the capture zone channel, the delivery channel, circulation channel, detection zone and capture zone channel forming a defined pathway through which the liquid sample flows from the through hole to the terminal end of the capture channel;

there being immobilized reagent in the capture zone channel which will react with said analyte to form a detectable product;

ii) applying a quantity of said fluid sample to said detection zone;

iii) permitting a sufficient period of time to elapse for the fluid sample to flow from the detection zone from said plurality of different directions to the capture zone channel and any said analyte therein to form a detectable reaction product at said capture zone; and

iv) identifying the presence of said at least one analyte in said fluid sample by detecting any said detectable reaction product at said capture zone.

54. The method of claim 53 wherein said at least one analyte is a cardiac analyte.

55. The method of claim 54 wherein three pathways are provided for identifying the presence of troponin I or troponin T together with identifying the presence of myoglobin and CK-MB.

56. The method of claim 53 wherein there is only one pathway provided for identifying the presence of troponin I or troponin T together with the identifying the presence of myoglobin and CK-MB.

57. The method of claim 53 wherein said sample circulation channel is arcuate.

58. The method of claim 53 wherein said border of said through hole is semicircular.

59. The method of claim 53 wherein said sample circulation channel is polygonal or forms part of a polygon.

60. The method of claim 59 wherein said sample circulation channel is rectangular or forms part of a rectangle.

61. The method of claim 53 wherein said border of said detection zone is polygonal or forms part of a polygon.

62. The method of claim 61 wherein said border of said detection zone is rectangular or forms part of a rectangle.