Immunoassay devices and materials

• US 5,559,041 A
• Filed: 06/03/1993
• Issued: 09/24/1996
• Est. Priority Date: 12/18/1989
• Status: Expired due to Term

• Current Assignee: PBM-Selfcare LLC (Abbott Laboratories Incorporated)
• Original Assignee: Princeton Biomeditech Corporation
• Inventors: Oh, Young H., Kang, Jemo, Youn, Byungwoo
• Primary Examiner(s): Housel, James C.
• Assistant Examiner(s): Chin, Christopher L.
• Application Number:
  US08/070,803
• Time in Patent Office: 1,209 Days
• Field of Search: 436/529, 436/530, 436/524, 436/805, 436/810, 436/518, 436/164, 436/169, 436/514, 435/7.92, 435/7.93, 435/7.94, 435/7.95, 435/970, 435/810, 422/56, 422/57, 422/60, 422/58
• US Class Current: 436/518
• CPC Class Codes: G01N 33/54366 Apparatus specially adapted for solid-phase testing
• CPC Class Codes: G01N 33/54388 based on lateral flow
• CPC Class Codes: G01N 33/54389 with bidirectional or multidirectional lateral flow, e.g. wherein the sample flows from a single, common sample application point into multiple strips, lanes or zones
• CPC Class Codes: G01N 33/558 using diffusion or migration of antigen or antibody immunochromatographic test strips G01N33/54387
• CPC Class Codes: Y10S 435/805 Test papers
• CPC Class Codes: Y10S 435/81 Packaged device or kit
• CPC Class Codes: Y10S 435/97 Test strip or test slide
• CPC Class Codes: Y10S 436/805 Optical property
• CPC Class Codes: Y10S 436/81 Tube, bottle, or dipstick

Abstract

An immunoassay reagent is disclosed comprised of carbon black and ligands which are coupled to the carbon black through a linking agent, together with a device comprised of the immunoassay reagent.

Claims

1. An immunochemical assay device comprising:

a base member;

an array disposed on said base member, said array comprising;

(i) a reservoir pad having sufficient porosity and volume to receive and contain a liquid sample on which the assay is to be performed;

(ii) a wicking membrane disposed distally to said reservoir pad, said wicking membrane having sufficient porosity and volume to absorb a substantial proportion of the sample received in said reservoir pad; and

(iii) at least one filter zone which is separate and distinct from said reservoir pad and wicking membrane, and interposed between and contiguous with said wicking membrane and said reservoir pad, said filter zone having impregnated therein a labelled immunochemical component capable of binding to an analyte of interest in said sample to form an immuno-complex, said filter zone being operable to permit passage of any specific immuno-complex to said wicking membrane while impeding passage of larger components then contained in said sample; and

at least one immobilized substance disposed in at least one assay indicia zone of said wicking membrane downstream of said reservoir pad and defining assay indicia, said immobilized substance being operable to bind a specific immuno-complex contained in the sample to form said assay indicia.

2. The assay device according to claim 1 in which the base member is plastic or glass.

3. The assay device according to claim 1 in which said reservoir pad extends beyond said base member.

4. The assay device according to claim 1 in which the label is a direct label.

5. The assay device according to claim 4 in which the label is a metal sol, a nonmetal sol, a dye sol, a color indicator, or particulate latex.

6. The assay device according to claim 5 in which the label is a carbon sol.

7. The assay device according to claim 1 in which the label is an indirect label.

8. The assay device according to claim 1 in which said analyte is selected from the group consisting of an antibody, antigen and a hapten.

9. The assay device according to claim 1 in which at least one of said immunochemical component and said immobilized substance is a monoclonal antibody.

10. The assay device according to claim 1 in which at least one of said immunochemical component and said immobilized substance is selected from the group consisting of a polyclonal antibody, an antigen and a hapten.

11. The assay device according to claim 1 in which said immobilized substance is a ligand.

12. The assay device according to claim 11 in which said immobilized substance is an antigen or hapten.

13. The assay device according to claim 1, further comprising

a second filter element disposed on said base member adjacent to first filter element and distal to said reservoir pad, said second filter element being operable to permit passage of any specific immuno-complex in said sample but impede passage of larger components then contained in said sample.

14. The assay device according to claim 13 in which each of said pad, first filter element, second filter element, and wicking membrane comprises microporous membrane material.

15. The assay device according to claim 14 in which each microporous membrane is selected from the group consisting of nylon, cellulosic material, polysulfone, polyvinylidene difluoride, polyester and glass fiber.

16. A device according to claim 1 including a moisture impervious envelope surrounding said device,

said envelope including

an aperture defined in said envelope, a surrounding upper surface of which is curved and extends downwards forming a cup-like receptacle terminating and firmly engaging a portion of said reservoir pad,

said aperture being operable to receive and meter a flow rate of liquid sample onto said reservoir pad, and a means operable to permit visual inspection of said assay indicia.

17. A device according to claim 1 including a moisture impervious envelope surrounding said device,

said envelope including

a first aperture defined in said envelope, a surrounding upper surface of which is curved and extends downwards forming a cup-like receptacle terminating and firmly engaging a portion of said reservoir pad,

said first aperture being operable to receive and meter a passage of buffer liquid onto said reservoir pad,

a second aperture defined in said envelope directly above said wicking membrane,

said second aperture being operable to permit direct application of sample onto said wicking membrane at a location between said reservoir pad and said assay indicia zone of said wicking membrane, and

a means operable to permit visual inspection of said assay indicia zone disposed above said assay indicia.

18. The assay device according to claim 17, wherein said immunochemical component is selected from the group consisting of an antibody, a hapten, and an antigen, said analyte is a first antibody specific for said antibody, hapten or antigen and said immobilized substance is selected from the group consisting of a second antigen, hapten and antibody, specific for a complex of said antibody, hapten or antigen and said first antibody.

19. The assay device according to claim 1, wherein said analyte is an antigen, said immunochemical component is a first antibody specific for said antigen and said immobilized substance is a second antibody specific for a complex of said antigen and said first antibody.

20. The assay device according to claim 1, wherein:

(a) the binding of said at least one immobilized substance specific for said immuno-complex immobilized in a first zone of said wicking membrane forms a positive assay indicia; and

(b) a second immobilized substance specific for unbound labelled immunochemical component is immobilized in a second zone of said wicking membrane whereby binding of said second immobilized substance to said unbound labelled immunochemical component forms a control assay indicia.

21. A device according to claim 20 including a moisture impervious envelope surrounding said device,

said envelope including

a first aperture defined in said envelope, a surrounding upper surface of which is curved and extends downwards forming a cup-like receptacle terminating and firmly engaging a portion of said reservoir pad,

said first aperture being operable to receive and meter a passage of liquid onto said reservoir pad,

a second aperture defined in said envelope directly above said wicking membrane,

said second aperture being operable to permit direct application of sample onto said wicking membrane at a location between said reservoir pad and said zone of said wicking membrane, and

a means operable to permit visual inspection of said assay indicia zone disposed above said assay indicia.

22. The immunochemical assay device according to claim 1, wherein

(a) at least two labelled immunochemical components are impregnated in said filter zone, each immunochemical component being capable of binding to a specific analyte of interest in said sample;

and

(b) at least two immobilized substances are disposed in separate assay indicia zones of said wicking membrane downstream of said reservoir pad, each immobilized substance being specific to bind to a different immuno-complex to form a positive assay indicia.

23. The immunochemical assay device according to claim 22, further comprising an additional immobilized substance specific for unbound labelled immunochemical component immobilized in an additional zone of said wicking membrane downstream of said assay indicia zone, whereby binding of said additional immobilized substance to said unbound labelled immunochemical component forms a control assay indicia.

24. The immunochemical assay device according to claim 1, further comprising

(a) at least two wicking membranes disposed distally to said reservoir pad;

(b) a first filter zone interposed between each of said wicking membranes and said reservoir pad, each first filter zone having impregnated therein a labelled immunochemical component capable of binding to a different analyte of interest in said sample to form an immunocomplex; and

(c) at least one immobilized substance disposed in at least one zone of each of said wicking membranes downstream of said reservoir pad and defining assay indicia, each immobilized substance being specific to a different one of said immuno-complex, whereby binding of said immobilized substance to said immuno-complex forms a positive assay indicia.

25. The immunochemical assay device according to claim 24, wherein a plurality of said wicking membranes are disposed radially from said reservoir pad.

26. An immunochemical assay device according to claim 1, wherein a moisture impervious plastic envelope surrounds said device and said envelope includes at least one aperture to permit visual inspection of said assay indicia.

27. An immunochemical assay device according to claim 26, wherein said reservoir pad extends beyond said base member.

28. An assay device according to claim 1, wherein said labelled immunochemical component is an antibody, hapten or antigen capable of binding to said analyte of interest to form an immunocomplex.

29. An assay device according to claim 28, wherein said immobilized substance is an antibody, hapten or antigen capable of binding to said immuno complex or said labelled immunochemical component.

48. The assay device according to claim 14 or claim 46 wherein the wicking membrane comprises nitrocellulose.

30. An immunochemical assay device comprising:

a base member;

a wicking membrane disposed on said base member;

a reservoir pad disposed on said base member and distal to said wicking membrane, said reservoir pad having sufficient porosity and volume to receive and contain a liquid sample on which the assay is to be performed;

a first filter which is distinct from, interposed between and contiguous with said wicking membrane and said reservoir pad, said reservoir pad overlapping said first filter element, said first filter having impregnated therein a first labelled immunochemical component capable of binding to an analyte of interest in said sample to form an immunocomplex, said first filter being operable to permit passage of any specific immuno-complex to said wicking membrane while impeding passage of larger components present in said sample;

a second immunochemical component specific for said immuno-complex immobilized in a first indicia zone of said wicking membrane downstream of said reservoir pad, whereby binding of said second immunochemical component to said immuno-complex forms a positive assay indicia; and

a third immobilized immunochemical component specific for said first immunochemical component not bound to said analyte and being immobilized in a second indica zone of said wicking membrane downstream of said second, immunochemical component whereby binding of said third antibody to said unbound first immunochemical component forms a control assay indicia.

31. The assay device according to claim 30, further comprising a second filter element disposed on said base member adjacent to first filter element and distal to said reservoir pad, said second filter element being operable to permit passage of any specific immuno-complex in said sample but impede passage of larger components then contained in said sample.

32. A device according to claim 30 including a moisture impervious envelope surrounding said device,

said envelope including

an aperture defined in said envelope, the surrounding upper surface of which is curved and extends downwards forming a cup-like receptacle terminating and firmly engaging a portion of said reservoir pad,

said aperture being operable to receive and meter the flow rate of liquid sample onto said reservoir pad, and a means operable to permit visual inspection of said assay indicia.

33. The immunochemical assay device according to claim 30, wherein said first filter element is in overlapping relation to said wicking membrane.

34. An immunochemical assay device comprising:

a base member;

an array disposed on said base member, said array comprising;

(i) a reservoir pad having sufficient porosity and volume to receive and contain a liquid sample on which the assay is to be performed;

(ii) a wicking membrane disposed distally to said reservoir pad, said wicking membrane having sufficient porosity and volume to absorb a substantial proportion of the sample received in said reservoir pad; and

(iii) at least one filter zone which is separate and distinct from said reservoir pad and wicking membrane, and interposed between and contiguous with said wicking membrane and said reservoir pad, said filter zone having impregnated therein a labelled immunochemical component capable of binding to an analyte of interest in said sample to form an immuno-complex, said filter zone being operable to permit passage of any specific immuno-complex to said wicking membrane while impeding passage of larger components then contained in said sample;

at least one immobilized substance disposed in at least one assay indicia zone of said wicking membrane downstream of said reservoir pad and defining assay indicia, said immobilized substance being operable to bind a specific immuno-complex contained in the sample to form said assay indicia; and

a moisture impervious envelope surrounding said base member and said assay indicia, said envelope including

an aperture define in said envelope, a surrounding upper surface of which is curved and extends downwards forming a cup-like receptacle terminating and firmly engaging a portion of said reservoir pad,

said aperture being operable to receive and meter a flow rate of liquid sample onto said reservoir pad, and a means operable to permit visual inspection of said assay indicia.

35. The assay device according to claim 34 in which the base member is plastic or glass.

36. The assay device according to claim 34 in which said reservoir pad extends beyond said base member.

37. The assay device according to claim 34 in which the label is a direct label.

38. The assay device according to claim 37 in which the label is a metal sol, a nonmetal sol, a dye sol, a color indicator, or particulate latex.

39. The assay device according to claim 38 in which the label is a carbon sol.

40. The assay device according to claim 34 in which the label is an indirect label.

41. The assay device according to claim 34 in which at least one of said immunochemical component and said immobilized substance is a monoclonal antibody.

42. The assay device according to claim 34 in which at least one of said immunochemical component and said immobilized substance is a polyclonal antibody.

43. The assay device according to claim 34 in which said immobilized substance is a ligand.

44. The assay device according to claim 43 in which said immobilized substance is an antigen or hapten.

45. The assay device according to claim 34, further comprising

a second filter element disposed on said base member adjacent to first filter element and distal to said reservoir pad, said second filter element being operable to permit passage of any specific immuno-complex in said sample but impede passage of larger components then contained in said sample.

46. The assay device according to claim 45 in which each of said pad, first filter element, second filter element, and wicking membrane comprises microporous membrane material.

47. The assay device according to claim 46 in which each microporous membrane is selected from the group consisting of nylon, cellulosic material, polysulfone, polyvinylidene difluoride, glass fiber and polyester.

49. The assay device according to claim 34, wherein said analyte is an antigen, said labelled immunochemical component is a first labelled antibody specific for said antigen and said immobilized substance is a second antibody specific for a complex of said antigen and said first labelled antibody.

50. The assay device according to claim 34, wherein said labelled immunochemical component is selected from the group consisting of a hapten and an antigen, said analyte is a first antibody specific for said hapten or antigen and said immobilized substance is a second antibody specific for a complex of said hapten, or antigen and said first antibody.

51. The assay device according to claim 34, wherein:

(a) the binding of said at least one immobilized substance specific for said immuno-complex immobilized in a first zone of said wicking membrane forms a positive assay indicia; and

(b) a second immobilized substance specific for unbound labelled immunochemical components is immobilized in a second zone of said wicking membrane whereby binding of said second immobilized substance to said unbound labelled immunochemical component forms a control assay indicia.

52. The immunochemical assay device according to claim 34, wherein

(a) at least two labelled immunochemical components are impregnated in said filter zone, each labelled immunochemical component being capable of binding to a specific analyte of interest in said sample;

and

(b) at least two immobilized substances are disposed in separate assay indicia zones of said wicking membrane downstream of said reservoir pad, each immobilized substance being specific to bind to a different immuno-complex to form a positive assay indicia.

53. The immunochemical assay device according to claim 52, further comprising an additional immobilized substance specific for unbound labelled immunochemical component immobilized in an additional zone of said wicking membrane downstream of said assay indicia zone, whereby binding of said additional immobilized substance to said unbound labelled immunochemical component forms a control assay indicia.

54. The immunochemical assay device according to claim 34, further comprising

(a) at least two wicking membranes disposed distally to said reservoir pad;

(b) a first filter zone interposed between each of said wicking membranes and said reservoir pad, each first filter zone having impregnated therein a labelled immunochemical component capable of binding to a different analyte of interest in said sample to form an immuno-complex; and

(c) at least one immobilized substance disposed in at least one zone of each of said wicking membranes downstream of said reservoir pad and defining assay indicia, each immobilized substance being specific to a different one of said immuno-complex, whereby binding of said immobilized substance to said immunocomplex forms a positive assay indicia.

55. The immunochemical assay device according to claim 54, wherein a plurality of said wicking membranes are disposed radially from said reservoir pad.

56. An immunochemical assay device comprising:

a base member;

an array disposed on said base member, said array comprising;

(i) a reservoir pad having sufficient porosity and volume to receive and contain a liquid sample on which the assay is to be performed;

(ii) a wicking membrane disposed distally to said reservoir pad, said wicking membrane having sufficient porosity and volume to absorb a substantial proportion of the sample received in said reservoir pad; and

(iii) at least one filter zone which is separate and distinct from said reservoir pad and wicking membrane, and interposed between and contiguous with said wicking membrane and said reservoir pad, said filter zone having impregnated therein a labelled immunochemical component analogous to said analyte, said filter zone being operable to permit passage of any labelled immunochemical component or analyte to said wicking membrane while impeding passage of larger components then contained in said sample; and

at least one immobilized substance disposed in at least one assay indicia zone of said wicking membrane downstream of said reservoir pad and defining assay indicia, said immobilized substance being operable to bind said labelled immunochemical component or said analyte.

57. An immunochemical assay device comprising:

a base member;

a wicking membrane disposed on said base member;

a reservoir pad disposed on said base member and distal to said wicking membrane, said reservoir pad having sufficient porosity and volume to receive and contain a liquid sample on which the assay is to be performed;

a first filter which is distinct from, interposed between and contiguous with said wicking membrane and said reservoir pad, said reservoir pad overlapping said first filter element, said first filter having impregnated therein a first labelled immunochemical component analogous to said analyte, said first filter being operable to permit passage of any labelled immunochemical component or analyte to said wicking membrane while impeding passage of larger components present in said sample;

a second immunochemical component specific for said first labelled immunochemical component immobilized in a first indicia zone of said wicking membrane downstream of said reservoir pad, whereby binding of said substance to said first labelled immunochemical component forms a negative assay indicia; and

a third immobilized immunochemical component specific for said first labelled immuno-chemical component being immobilized in a second indica zone of said wicking membrane downstream of said immobilized substance, whereby binding of said third immunochemical component to said first immunochemical component forms a control assay indicia.

58. The assay device according to claim 57 wherein said immobilized substance is an antibody, antigen or hapten.