Concentrating immunochemical test device and method

• US 5,716,778 A
• Filed: 05/15/1989
• Issued: 02/10/1998
• Est. Priority Date: 02/14/1985
• Status: Expired due to Fees

• Current Assignee: Abbott Laboratories
• Original Assignee: Abbott Laboratories
• Inventors: Khanna, Pyare, Weng, Litai, Calderhead, David, Ullman, Edwin F.
• Primary Examiner(s): Scheiner, Laurie A.
• Application Number:
  US07/351,976
• Time in Patent Office: 3,193 Days
• Field of Search: 422/55, 422/56, 422/61, 436/536, 436/65, 436/814, 435/4, 435/5, 435/7.1, 435/7.9, 435/7.92, 435/7.93, 435/7.94, 435/7.95, 435/805, 435/806, 435/970, 435/971, 435/975
• US Class Current: 435/4
• CPC Class Codes: G01N 33/538 by sorbent column, particles or resin strip , i.e. sorbent materials
• CPC Class Codes: G01N 33/542 with steric inhibition or signal modification, e.g. fluorescent quenching
• CPC Class Codes: G01N 33/54313 the carrier being characterised by its particulate form
• CPC Class Codes: G01N 33/54386 Analytical elements
• 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 435/805 Test papers
• CPC Class Codes: Y10S 435/966 involving an enzyme system with high turnover rate or complement magnified assay, e.g. multi-enzyme systems
• CPC Class Codes: Y10S 435/97 Test strip or test slide
• CPC Class Codes: Y10S 435/973 Simultaneous determination of more than one analyte
• CPC Class Codes: Y10S 435/975 Kit
• CPC Class Codes: Y10S 436/81 Tube, bottle, or dipstick
• CPC Class Codes: Y10S 436/814 Pregnancy
• CPC Class Codes: Y10S 436/818 Human chorionic gonadotropin

Abstract

A method and device for determining the presence of an analyte in a sample suspected of containing the analyte is disclosed. The method involves contacting a test solution containing the sample and a first member of a specific binding pair with an end portion of a strip of bibulous material capable of being traversed by the test solution through capillary action. The first member of a specific binding pair is capable of binding the analyte. The strip contains a second member of a specific binding pair integral therewith for concentrating and non-diffusively binding the first sbp member at a small situs on the strip separated from the end portion of the strip. The detectible signal is produced in relation to the presence of the analyte in the test solution. The test solution passes through the situs as the test solution traverses the bibulous material. After the test solution has been allowed to traverse at least a portion of the strip, the strip is contacted with a developer solution containing members of a signal producing system in a manner that provides contact of the developer solution with the small situs following its contact with the test solution. The strip is then contacted with any remaining members of the signal producing system. The detectible signal produced at the situs is then compared with the signal detectible at a portion of the strip other than the situs to determine the analyte in the sample. In one embodiment of the invention the signal produced at the small situs has a sharp-edged distinctive pattern that provides a sharp contrast to the signal produced at adjacent sites on the strip when analyte is present in the test solution.

Claims

1. A method for determining the presence of an analyte in a sample suspected of containing said analyte, which method comprises

(a) providing in combination (1) a liquid medium containing said sample and a first sbp member and (2) a portion of bibulous material capable of being traversed by said liquid medium by capillary migration,

said bibulous material containing a second sbp member non-diffusively bound to a small situs on said bibulous material separated from said portion, the surface area of said situs being substantially less than that of said bibulous material,

said second sbp member having the characteristic of binding said first sbp member

wherein a third sbp member capable of binding said first sbp member is non-diffusively bound to said bibulous material at least between said small situs and said portion,

(b) allowing said liquid medium to traverse at least a portion of said bibulous material by means of capillary migration, and

(c) detecting the presence or absence of the first sbp member at said situs.

2. The method of claim 1 wherein said bibulous material is in the form of a strip.

3. The method of claim 1 wherein said first sbp member is an antibody.

4. The method of claim 1 wherein second sbp member is non-diffusively bound to said small situs by virtue of particles non-diffusively bound to said bibulous material at said situs, said particles being conjugated to said second sbp member.

5. The method of claim 1 wherein said first sbp member is conjugated to a label.

6. The method of claim 5 wherein said first sbp member is detected at said situs by detecting said label.

7. The method of claim 1 wherein the analyte is a drug and said third sbp member is a drug analog which is non-diffusively bound to said bibulous material.

8. The method of claim 1 wherein the small situs is a band transverse to the direction of traversal of said liquid medium along said bibulous material.

9. The method of claim 1 for determining the presence of a plurality of analytes in said sample, wherein a plurality of corresponding second sbp members are each non-diffusively bound to a small situs on said bibulous material distant from said portion wherein each of said second sbp members is respectively capable of specifically binding a corresponding first sbp member and said first sbp members are provided in combination with said sample and said portion in said liquid medium.

10. A method for determining the presence of an analyte in a sample suspected of containing said analyte, which comprises

(a) contacting, with a test solution containing said sample and a first sbp member, a contact portion of bibulous material capable of being traversed by said test solution by capillary migration,

said bibulous material containing a second sbp member non-diffusively bound to a small situs on said bibulous material separate from said contact portion, the surface area of said situs being substantially less than that of said bibulous material,

said second sbp member having the characteristic of binding said first sbp member

wherein a third sbp member capable of binding said first sbp member is non-diffusively bound to said bibulous material at least between said small situs and said portion,

(b) allowing said liquid medium to traverse at least a portion of said bibulous material by means of capillary migration, and

(c) detecting the presence or absence of the first sbp member at said situs.

11. The method of claim 10 wherein said bibulous material is in the form of a strip.

12. The method of claim 10 wherein said first sbp member is an antibody.

13. The method of claim 10 wherein second sbp member is non-diffusively bound to said small situs by virtue of particles non-diffusively bound to said bibulous material at said situs, said particles being conjugated to said second sbp member.

14. The method of claim 10 wherein said first sbp member is conjugated to a label.

15. The method of claim 14 wherein said first sbp member is detected at said situs by detecting said label.

16. The method of claim 10 wherein the analyte is a drug and said third sbp member is a drug analog which is non-diffusively bound to said bibulous material.

17. The method of claim 10 wherein the small situs is a band transverse to the direction of traversal of said liquid medium along said bibulous material.

18. The method of claim 10 for determining the presence of a plurality of analytes in said sample, wherein a plurality of corresponding second sbp members are each non-diffusively bound to a small situs on said bibulous material distant from said portion wherein each of said second sbp members is respectively capable of specifically binding a corresponding first sbp member and said first sbp members are provided in combination with said sample and said portion in said liquid medium.

19. A method for determining the presence of one or more of a plurality of analytes in a sample suspected of containing said analytes, which method comprises

(a) providing in combination (1) a liquid medium containing said sample and a plurality of first sbp members and (2) a portion of bibulous material capable of being traversed by said liquid medium by capillary migration,

said bibulous material containing a plurality of second sbp members each non-diffusively bound to a small situs on said bibulous material separated from said portion, the surface area of said situses being substantially less than that of said bibulous material,

each of said second sbp members having the characteristic of binding a corresponding first sbp member

wherein a plurality of third sbp members each capable of binding one of said first sbp members are non-diffusively bound to said bibulous material at least between said small situs and said portion,

(b) allowing said liquid medium to traverse at least a portion of said bibulous material by means of capillary migration, and

(c) detecting the presence or absence of the first sbp members at said situses.

20. The method of claim 19 wherein said bibulous material is in the form of a strip.

21. The method of claim 19 wherein each of said first sbp members is an antibody.

22. The method of claim 19 wherein said second sbp members are each non-diffusively bound to said small situs by virtue of particles non-diffusively bound to said bibulous material at said situs, said particles being conjugated to said second sbp members.

23. The method of claim 19 wherein said first sbp members are each conjugated to a label.

24. The method of claim 23 wherein said first sbp members are detected at said situs by detecting said labels.

25. The method of claim 19 wherein said analytes are drugs and said third sbp members are a drug analogs which are non-diffusively bound to said bibulous material.

26. The method of claim 19 wherein each of said small situses is a band transverse to the direction of traversal of said liquid medium along said bibulous material.

27. A method for determining the presence of one or more of a plurality of analytes in a sample suspected of containing said analyte, which comprises

(a) contacting, with a test solution containing said sample and a plurality of first sbp members, a contact portion of bibulous material capable of being traversed by said test solution by capillary migration,

said bibulous material containing a plurality of second sbp members each non-diffusively bound to a small situs on said bibulous material separate from said contact portion, the surface area of each of said situses being substantially less than that of said bibulous material,

each of said second sbp members having the characteristic of binding a corresponding first sbp member

wherein a plurality of third sbp members each capable of binding one of said first sbp members are non-diffusively bound to said bibulous material at least between said small situs and said portion,

(b) allowing said liquid medium to traverse at least a portion of said bibulous material by means of capillary migration, and

(c) detecting the presence or absence of the first sbp member at said situs.

28. The method of claim 27 wherein said bibulous material is in the form of a strip.

29. The method of claim 27 wherein each of said first sbp members is an antibody.

30. The method of claim 27 wherein said second sbp members are each non-diffusively bound to said small situs by virtue of particles non-diffusively bound to said bibulous material at said situs, said particles being conjugated to said second sbp members.

31. The method of claim 27 wherein said first sbp members are each conjugated to a label.

32. The method of claim 31 wherein said first sbp members are detected at said situs by detecting said labels.

33. The method of claim 27 wherein said analytes are drugs and said third sbp members are drug analogs which are non-diffusively bound to said bibulous material.

34. The method of claim 27 wherein each of said small situses is a band transverse to the direction of traversal of said liquid medium along said bibulous material.

35. A method for determining the presence of one or more of a plurality of analytes in a sample suspected of containing said analytes, which comprises

(a) contacting, with a test solution containing said sample and a plurality of antibodies each corresponding to one of said analytes, and each of said antibodies being conjugated to a label (antibodies--labels), a contact portion of bibulous material capable of being traversed by said test solution by capillary migration,

said bibulous material containing sets of particles, each of said sets being non-diffusively bound to a small situs on said bibulous material separate from said contact portion, the surface area of said situs being substantially less than that of said bibulous material,

said particles having a plurality of sets of members of specific binding pairs ("sbp members") non-diffusively bound thereto, each set of sbp members being respectively capable of binding to one of said antibodies to said analyte when said antibodies are bound to said analyte,

with the proviso that, where said sbp members are able of binding said antibodies to said analyte when said antibodies are not bound to said analyte, a plurality of analogs of said analytes each capable of binding to one of said antibodies to said analyte are non-diffusively bound to said bibulous material between said small situs and said contact portion,

(b) allowing the test solution to traverse at least a portion of said bibulous material by capillary migration, and

(c) detecting the presence or absence of said antibodies-labels at the situs.

36. The method of claim 35 wherein said bibulous material is in the form of a strip.

37. The method of claim 35 wherein each of said antibodies are labelled with an enzyme.

38. The method of claim 35 wherein said small situs is a band traverse to the direction of traversal of said sample along said bibulous material.

39. The method of claim 35 wherein said analytes are drugs and drug analog for each of said drugs is non-diffusively bound to the bibulous material.

40. A method for determining the presence of an analyte in a sample suspected of containing said analyte, which comprises

(a) contacting, with a test solution containing said sample and a first sbp member, a contact portion of bibulous material capable of being traversed by said test solution by capillary migration,

said bibulous material containing particles non-diffusively bound to a small situs on said bibulous material separate from said contact portion, the surface area of said situs being substantially less than that of said bibulous material,

said particles having a member of a specific binding pair ("sbp member") non-diffusively bound thereto, which sbp member is capable of binding to said antibodies to said analyte when said antibodies are bound to said analyte,

with the proviso that, where said sbp member is able to bind said antibodies to said analyte when said antibodies are not bound to said analyte, an analog of said analyte capable of binding said antibodies to said analyte is non-diffusively bound to said bibulous material between said small situs and said contact portion,

(b) allowing said test solution to traverse at least a portion of said bibulous material by capillary migration, and

(c) detecting the presence or absence of said antibodies at said situs.

41. The method of claim 40 wherein said bibulous material is in the form of a strip.

42. The method of claim 40 wherein said antibodies to said analyte are antibodies for human chlorionic gonadotropin.

43. The method of claim 40 wherein said sbp member is antibody for human chorionic gonadotropin.

44. The method of claim 40 wherein said antibodies are labelled with an enzyme.

45. The method of claim 44 wherein a second enzyme is bound to said bibulous material, the enzyme being related in that the product of one enzyme is the substrate of the other.

46. The method of claim 40 for determining a plurality of analytes in said sample, wherein a mixture of specific antibodies to each analyte is combined with the sample and a plurality of corresponding sbp members are each non-diffusively bound to a small situs on said bibulous material wherein each of said sbp members is capable of binding at lease one of the complexes formed between a specific antibody and an analyte.

47. The method of claim 46 wherein an analyte analog for each of said analytes is bound to said bibulous material.

48. The method of claim 40 wherein small situs is a band transverse to the direction of traversal of said sample along said bibulous material.

49. A method of claim 40 wherein said analyte is a drug and a drug analog is non-diffusively bound to the bibulous material.

50. A method for determining the presence of an analyte in sample suspected of containing said analyte, which analyte is a member of a specific binding pair ("sbp member") consisting of ligand and its complementary receptor, which method comprises

(a) providing in combination (1) a liquid medium containing said sample and a first sbp member capable of binding to said analyte, and (2) a portion of bibulous material capable of being traversed by said liquid medium by capillary migration,

said bibulous material containing a second sbp member non-diffusively bound to a small situs on said bibulous material separated from said portion, the surface area of said situs being substantially less than that of said bibulous material,

said second sbp member having the characteristic of binding said first sbp member when said first sbp member is bound to said analyte,

with the proviso that, where said second sbp member is able to bind said first sbp member when said first sbp member is not bound to said analyte, an analyte analog capable of binding said first sbp member is non-diffusively bound to said bibulous material at least between said small situs and said portion,

(b) allowing said liquid medium to traverse at least a portion of said bibulous material by means of capillary migration, and

(c) detecting the presence or absence of the first sbp member at said situs.

51. The method of claim 50 wherein said bibulous material is in the form of a strip.

52. The method of claim 50 wherein said first sbp member is an antibody.

53. The method of claim 50 wherein particles are non-diffusively bound to said bibulous material at said situs, said particles being conjugated to said second sbp member.

54. The method of claim 50 wherein said first sbp member is conjugated to a label.

55. The method of claim 50 wherein said first sbp member is detected at said situs by detecting said label.

56. The method of claim 50 wherein the analyte is a drug and the analyte analog is a drug analog which is non-diffusively bound to said bibulous material.

57. The method of claim 50 wherein the small situs is a band transverse to the direction of traversal of said liquid medium along said bibulous material.

58. The method of claim 50 for determining the presence of a plurality of analytes in said sample, wherein a plurality of corresponding second sbp members are each non-diffusively bound to a small situs on said bibulous material distant from said portion wherein each of said second sbp members is respectively capable of specifically binding a corresponding first sbp member and said first sbp members are provided in combination with said sample and said portion in said liquid medium.

59. A method for determining the presence of an analyte, which comprises

(a) providing in combination (1) a liquid medium containing said analyte and antibodies to said analyte, said antibodies being conjugated to a label, and (2) a portion of a strip of bibulous material capable of being traversed by said liquid medium by capillary migration,

said bibulous material containing particles non-diffusively bound to a small situs on said bibulous material separate from said portion,

the surface area of said situs being substantially less than that of said bibulous material,

said particles having a member of a specific binding pair ("sbp member") non-diffusively bound thereto, which sbp member is capable of binding to said antibodies to said analyte when said antibodies are bound to said analyte,

with the proviso that, where said sbp member is able to bind said antibodies to said analyte when said antibodies are not bound to said analyte, an analog of said analyte capable of binding said antibodies to said analyte is non-diffusively bound to said bibulous material between said small situs and said portion,

(b) allowing the liquid medium to traverse at least a portion of said bibulous material by capillary migration, and

(c) detecting the presence or absence of said first sbp member at the situs.

60. The method of claim 59 wherein said bibulous material is in the form of a strip.

61. The method of claim 59 wherein said antibodies to said analyte are antibodies for human chorionic gonadotropin.

62. The method of claim 59 wherein said sbp member is antibody for human chorionic gonadotropin.

63. The method of claim 59 wherein said antibodies are labelled with an enzyme.

64. The method of claim 63 wherein a second enzyme is bound to said bibulous material, the enzymes being related in that the product of one enzyme is the substrate of the other.

65. The method of claim 59 for determining a plurality of analytes in said sample, wherein a mixture of specific antibodies to each analyte is provided in combination with the sample and the portion of this bibulous material and a plurality of corresponding sbp members are each non-diffusively bound to a small situs on said bibulous material wherein each of said sbp members is capable of binding at least one of the complexes formed between a specific antibody and an analyte.

66. The method of claim 65 wherein an analyte analog for each of said analytes is bound to said bibulous material.

67. The method of claim 59 wherein said small situs is a band traverse to the direction of traversal of said liquid medium along said bibulous material.

68. The method of claim 59 wherein said analyte is a drug and a drug analog is non-diffusively bound to the bibulous material.

69. A method for determining the presence of an analyte, which method comprises

(a) providing in combination (1) a liquid medium containing said analyte and a first sbp member capable of binding to said analyte, and (2) a portion of bibulous material capable of being traversed by said liquid medium by capillary migration,

said bibulous material containing a second sbp member non-diffusively bound to a small situs on said bibulous material separated from said portion, the surface area of said situs being substantially less than that of said bibulous material,

said second sbp member having the characteristic of binding said first sbp member when said first sbp member is bound to said analyte,

with the proviso that, where said second sbp member is able to bind said first sbp member when said first sbp member is not bound to said analyte, an analyte analog capable of binding said first sbp member is non-diffusively bound to said bibulous material at least between said small situs and said portion,

(b) allowing said liquid medium to traverse at least a portion of said bibulous material by means of capillary migration, and

(c) detecting the presence or absence of the first sbp member at said situs.

70. The method of claim 69 wherein said bibulous material is in the form of a strip.

71. The method of claim 69 wherein said first sbp member is an antibody.

72. The method of claim 69 wherein particles are non-diffusively bound to said bibulous material at said situs, said particles being conjugated to said second sbp member.

73. The method of claim 69 wherein said first sbp member is conjugated to a label.

74. The method of claim 73 wherein said first sbp member is detected at said situs by detecting said label.

75. The method of claim 69 wherein the analyte is a drug and the analyte analog is a drug analog which is non-diffusively bound to said bibulous material.

76. The method of claim 69 wherein the small situs is a band transverse to the direction of traversal of said liquid medium along said bibulous material.

77. The method of claim 69 for determining the presence of a plurality of analytes in said sample, wherein a plurality of corresponding second sbp members are each non-diffusively bound to a small situs on said bibulous material distant from said portion wherein each of said second sbp members is respectively capable of specifically binding a corresponding first sbp member and said first sbp members are provided in combination with said sample and said portion in said liquid medium.

78. A device for determining the presence of an analyte, which device comprises a bibulous material, the pores of at least a portion of which have particles infiltrated in the form of a pattern therein, said particles having a member of a specific binding pair non-diffusively bound thereto.

79. The device of claim 78 wherein said sbp member is an antibody.

80. The device of claim 78 wherein said sbp member is a ligand.

81. The device of claim 78 wherein said pattern is a dot.

82. The device of claim 78 wherein said pattern is a line.

83. The device of claim 78 wherein said pattern is a curve.

84. The device of claim 78 wherein said pattern is an abbreviated name of an analyte.

85. The device of claim 78 wherein said pattern is a plus sign.

86. The device of claim 78 wherein said particles are non-diffusively bound within said pores.

87. The device of claim 78 wherein said particles are latex particles.

88. The device of claim 78 which further comprises a support for said bibulous material.

89. The device of claim 78 wherein a plurality of patterns are formed on said bibulous material.

90. The device of claim 78 wherein said patterns are the same.

91. The device of claim 78 wherein each of said patterns are different.

92. A device for determining the presence of an analyte in a test solution comprised of a first member of a specific binding pair and a sample of containing the analyte, which comprises

bibulous material capable of traversal by said test solution by capillary migration, said bibulous material having a first portion for contacting said test solution ("contact portion") and a second sbp member non-diffusively bound to a second portion of said bibulous material, separated from said contact portion, the surface area of said second portion being substantially less than that of said bibulous material, said second sbp member having the characteristic of binding said first sbp member, and a third sbp member, capable of binding said first sbp member, non-diffusively bound to said bibulous material at least between said second portion and said contact portion.

93. The device of claim 92 wherein said bibulous material is a paper strip.

94. The device of claim 92 wherein said first sbp member is an antibody.

95. The device of claim 92 wherein particles are non-diffusively bound to said portion, said particles being conjugated to said second sbp member.

96. The device of claim 92 wherein said third sbp member is an analyte analog.

97. The device of claim 92 wherein the analyte is a drug.

98. The device of claim 93 wherein the portion is a band transverse to the direction of traversal of said test solution along said strip.

99. The device of claim 92 wherein the signal produced at said portion has a sharp-edged distinctive pattern.

100. The device of claim 92 wherein said first sbp member is conjugated to an enzyme and a second enzyme is bound to said bibulous material, the enzymes being related in that the product of one enzyme is the substrate for the others.

101. The device of claim 92 for determining the presence of a plurality of analytes in said test solution wherein each of a set of first sbp members is respectively non-diffusively bound to a different small portion on said strip separate from said contact portion wherein each set of sbp members is capable of binding to a specific complex of an analyte and a second sbp member.

112. A kit for determining the presence of an analyte in a test solution, comprising in a packaged combination

(a) the device of claim 92,

(b) other members of a signal producing system for producing a detectible signal in the presence of said analyte as required, and

(c) ancillary materials as required.

102. A device for determining the presence of an analyte in a test solution comprised of a first specific binding pair (sbp) member and a sample suspected of containing said analyte, which comprises

a strip of bibulous material capable of being traversed by said test solution by capillary migration, said strip having an end portion for contacting said test solution and

a second sbp member non-diffusively bound to said strip at a small situs separated from said end portion, said situs having a surface area substantially less than that of said strip, through which situs said test solution passes as it traverses said strip, and

a third sbp member, capable of binding said first sbp member, non-diffusively bound to said strip at least between said small situs and said end portion.

103. The device of claim 102 wherein said strip of bibulous material is a paper strip.

104. The device of claim 102 wherein said first sbp member is an antibody.

105. The device of claim 102 wherein particles are non-diffusively bound to said strip at said situs, said particles being conjugated to said second sbp member.

106. The device of claim 102, wherein said third sbp member is an analyte analog.

107. The device of claim 102 wherein the analyte is a drug.

108. The device of claim 102 wherein the small situs is a band transverse to the direction of traversal of said test solution along said strip.

109. The device of claim 102 wherein the signal produced at the small situs has a sharp-edged distinctive pattern.

110. The device of claim 102 wherein said first sbp member is conjugated to an enzyme and a second enzyme is bound to said strip, the enzymes being related in that the product of one enzyme is the substrate for the other.

111. The device of claim 102 for determining the presence of a plurality of analytes in said test solution wherein each of a set of first sbp members is respectively non-diffusively bound to a different small situs on said strip separate from said end portion wherein each set of sbp member is capable of binding to a specific complex of an analyte and a second sbp member.

113. A multizone test device for the specific binding assay determination of an analyte in a liquid test medium involving binding among (i) the analyte, (ii) a labeled or immobilized form of the analyte or of a binding analog thereof, and (iii) an immobilized or labeled form, respectively, of a binding partner of the analyte;

the labeled one of the analyte, analog thereof, or binding partner being a labeled reagent comprising a detectable chemical group having a detectable physical property, the test device comprising, in fluid flow contact,

(1) a reagent zone comprising a solid, porous matrix incorporated with an immobilized one of the analyte, analog thereof, or binding partner, and

(2) a detection zone comprising a solid, porous matrix for receiving and measuring labeled reagent which migrates into said detection zone and incorporated with an immobilized form of a binding substance for the labeled reagent.

114. The test device of claim 113 wherein the labeled reagent comprises an antibody, or a fragment thereof having an intact binding site for protein A, and the binding substance for the labeled reagent immobilized in the detection zone.

115. The test device of claim 113 wherein the labeled reagent is incorporated in said reagent zone and comprises a detectable chemical group, is a fluorescer or a chromophore.

116. The test device of claim 113 wherein the binding substance for the labeled reagent is immobilized in the detection zone by being covalently couples to the matrix comprised therein.

117. The test device of claim 113 wherein the binding substance for the labeled reagent is immobilized in the detection zone by being attached to a high molecular weight polymeric substance dispersed in said matrix.

118. The test device of claim 113 wherein the binding partner for the analyte is an antibody or a fragment thereof.

119. The test device of claim 113 which comprises a solid, porous chromatographic element and wherein the reagent and detection zones are discrete sections of such element.

120. The test device of claim 113 wherein the immobilized binding substance for the labeled reagent in the detection zone is an antibody, or a fragment thereof, which binds the labeled reagent.

121. The test device of claim 120 wherein the labeled reagent comprises an antibody, or a fragment thereof, to the analyte and the binding substance for the labeled reagent immobilized in the detection zone is an antibody, or a fragment thereof, to said anti-analyte antibody or fragment thereof.

122. The test device of claim 113 wherein the immobilized binding substance for the labeled reagent in the detection zone is an adsorbent material for the labeled reagent.

123. The test device of claim 122 wherein the absorbent material is an ion exchange material.

124. The test device of claim 113 wherein the labeled reagent is incorporated in said reagent zone and additionally comprises a ligand moiety and the immobilized binding substance for the labeled reagent in the detection zone is a binding partner of such ligand moiety.

125. The test device of claim 124 wherein the ligand moiety is a carbohydrate or a lectin which specifically binds therewith, and the binding partner for the ligand moiety is the other thereof.

126. The test device of claim 124 wherein the binding partner of the ligand moiety is a protein which specifically recognizes such moiety.

127. The test device of claim 126 wherein the ligand moiety is biotin or avidin, and the binding partner for the ligand moiety is the other thereof.

128. The test device of claim 126 wherein the protein which specifically recognizes the ligand moiety is an antibody or a fragment thereof.

129. The test device of claim 128 wherein the ligand moiety is a hapten.