Simultaneous calibration heterogeneous immunoassay

• US 5,156,953 A
• Filed: 04/04/1989
• Issued: 10/20/1992
• Est. Priority Date: 12/26/1979
• Status: Expired due to Term

• Current Assignee: DADE Behring Beteiligungs GmbH (Siemens AG)
• Original Assignee: Syntec Incorporated (Atos SE)
• Inventors: Ullman, Edwin F., Litman, David J.
• Primary Examiner(s): Kepplinger, Esther L.
• Assistant Examiner(s): Bidwell, Carol E.
• Application Number:
  US07/333,160
• Time in Patent Office: 1,295 Days
• Field of Search: 435/7.1, 435/7.9, 435/7.91, 435/7.92, 435/7.93, 435/7.4, 436/518, 436/528, 436/530, 436/810, 436/808
• US Class Current: 435/7.91
• CPC Class Codes: G01N 33/52 Use of compounds or compositions for colorimetric, spectrophotometric or fluorometric investigation, e.g. use of reagent paper and including single- and multilayer analytical elements immunological elements G01N33/54386; involving labelled immunochemicals G01N33/58; for haemoglobin or occult blood G01N33/72
• CPC Class Codes: G01N 33/542 with steric inhibition or signal modification, e.g. fluorescent quenching
• CPC Class Codes: G01N 33/54306 Solid-phase reaction mechanisms
• CPC Class Codes: G01N 33/581 with enzyme label (including co-enzymes, co-factors, enzyme inhibitors or substrates)
• CPC Class Codes: Y10S 435/967 Standards, controls, materials, e.g. validation studies, buffer systems
• CPC Class Codes: Y10S 435/97 Test strip or test slide
• CPC Class Codes: Y10S 436/81 Tube, bottle, or dipstick
• CPC Class Codes: Y10T 436/10 Composition for standardization, calibration, simulation, stabilization, preparation or preservation; processes of use in preparation for chemical testing

Abstract

An assay method and compositions are provided for determining the presence of an analyte in a sample. The analyte is a member of an immunological pair (mip) comprising ligand and receptor. By providing a first measurement surface capable of specifically binding a labelled reagent in an amount depending upon the presence of analyte in the sample and a second calibration surface capable of binding a second labelled reagent in a manner unaffected by the presence of analyte in the sample, calibration of individual tests can be accomplished simultaneously with the performance of the test itself. A signal producing system includes an enzyme, a catalyst usually bonded to a mip which defines the first labeled reagent for binding to the measurement surface and the same catalyst conjugated to a ligand capable of binding to the calibration surface. Preferably, both labeled reagents have the same composition and the calibration surface includes anti-(first catalyst).

Claims

1. In a method for determining the presence or amount of an analyte in an aqueous assay medium, which analyte is a member of a specific binding pair ("mip") consisting of ligand and receptor ("antiligand"):

said method employing a labeled mip, a signal producing system and a mip-containing measurement first surface, where the amount of labeled mip which binds to said first surface as a result of mip complex formation is related to the amount of analyte in said assay medium,

said method comprising the steps of contacting said first surface with said analyte in said assay medium and simultaneously or successively contacting said first surface with members of said signal producing system including at least said labeled mip which provides an amount of signal generating compound at said first surface related to the amount of analyte in said assay medium,

the improvement which comprises;

having in contact with said assay medium a calibration second surface containing a ligand or receptor, wherein said second surface provides a signal level from said signal generating compound as a result of at least one ligand-receptor binding selected from the group consisting of binding of complementary mips and binding of an enzyme with its substrate when the label of said labeled mip is an enzyme, whereby the intensity of the signal at said second surface compared to the intensity of the signal at said first surface defines the amount of analyte in said assay medium substantially independent of non-specific factors.

2. A method according to claim 1, wherein said labelled mip has a hub nucleus to which at least one mip is bound and a plurality of chemiluminescer or fluorescer molecules are bound.

3. A method according to claim 2, wherein a plurality of fluorescer molecules are bound to said hub nucleus.

4. In a method for determining the presence or amount in a sample of an analyte, which analyte is a member of a specific binding pair ("mip") consisting of ligand and receptor ("antiligand"),

said method employing at least one catalyst including a catalyst bound to a mip ("catalyst-bound-mip") and a solute which is catalytically transformed by a catalyst bound to a mip-containing measurement first surface to produce a detectable signal at said first surface in proportion to the amount of catalyst-bound-mip bound to said first surface, wherein contacting of said first surface with said sample and said catalyst-bound-mip results in binding of said catalyst-bound-mip to said first surface in proportion to the amount of analyst in said sample,

the improvement which comprises:

having in contact with an assay medium a mip-containing calibration second surface to which said catalyst specifically binds in an amount to produce a signal level at said second surface and determining said analyte in said sample substantially independent of non-specific factors by comparing the intensity of the signal at said first surface with the intensity of the signal at said second surface.

5. A method according to claim 4, wherein said catalyst is an enzyme.

6. A method according to claim 4, wherein said catalyst specifically binds to the mip on said second surface as the result of mip complex formation.

7. A method according to claim 4, wherein said catalyst-bound-mip is enzyme-bound-antiligand.

8. A method according to claim 4, wherein said catalyst-bound-mip is enzyme-bound-ligand.

9. A method according to claim 4, wherein said mip on said calibration second surface is anti-enzyme.

10. A method according to claim 4 wherein said mip of said catalyst-bound-mip is a first receptor and said mip on said calibration second surface is a second receptor for said first receptor.

11. A method according to claim 10 wherein said second receptor is anti-(antibody).

12. A method for conducting an assay for the presence or amount of an analyte in an aqueous medium, which comprises:

simultaneously contacting a mip-containing measurement surface and a ligand- or receptor-containing calibration surface with the same aqueous assay medium and the same assay environment wherein the amount of a catalyst-labeled mip that binds to said measurement surface as a result of mip complex formation is related to the amount of analyte in said medium and wherein the amount of catalyst that specifically binds to said calibration surface is independent of the amount of analyte in said medium, said catalyst being a member of a signal producing system, whereby a signal resulting from a catalyst on each of said surfaces is generated upon exposure of said surfaces to members of said signal producing system other than said catalyst and

comparing the intensities of signals at said measurement and calibration surfaces to determine the presence or amount of said analyte in said aqueous assay medium.

13. A method for conducting an assay for the presence or amount of an analyte in an aqueous assay medium, which comprises:

contacting with the same assay environment in an aqueous assay medium (1) a measurement surface, having bound thereto a specific binding pair member ("mip"), to which surface a catalyst-mip conjugate specifically binds in relation to the amount of an analyte in said aqueous assay medium and (2) a mip-containing calibration surface to which an amount of catalyst specifically binds that is substantially independent of the amount of analyte in said aqueous assay medium said catalyst being a member of a signal producing system, whereby a signal is generated on each of said surfaces upon exposure to members of said signal producing system other than said catalyst and

comparing the intensity of the signal at said measurement surface with the intensity of the signal at said calibration surface to determine the presence or amount of said analyte.

14. A method according to claim 13, wherein said mip of said calibration surface is anti-catalyst.

15. A method according to claim 14, wherein said catalyst is an enzyme and said anti-catalyst is anti-enzyme.

16. A method according to claim 13, wherein the mip of said catalyst-mip conjugate is an antibody and the mip of said calibration surface is anti-(antibody).

17. In a method for determining the presence or amount in a sample of an analyte, wherein said analyte is a member of a specific binding pair ("mip") consisting of ligand and receptor ("antiligand"),

said method employing at least one catalyst including a catalyst bound to a mip ("catalyst-bound-mip") and a solute which is catalytically transformed by a catalyst bound to a mip-containing measurement first surface to produce a detectable signal at said first surface in relation to the amount of catalyst-bound-mip bound to said first surface wherein contacting of said first surface with said sample in an assay medium containing said catalyst-bound-mip which results in binding of said catalyst-bound-mip to said first surface in relation to the amount of analyte in said sample,

the improvement which comprises:

having in contact with said assay medium a calibration second surface to which anti-catalyst is bound in an amount to cause binding of said catalyst-bound-mip, thereby producing a signal at said second surface and determining the presence or amount of said analyte in said sample by comparing the intensity of said signal at said first surface to the intensity of said signal at said second surface.

18. A method according to claim 17, wherein said catalyst is an enzyme and said anti-catalyst is anti-enzyme.

19. A method according to claim 18 wherein anti-catalyst is directly bound to said second surface.

20. In a method for determining the presence or amount in a sample of an analyte, wherein said analyte is a member of a specific binding pair ("mip") consisting of ligand and receptor ("antiligand"),

said method employing (1) at least one catalyst including a catalyst bound to a mip ("catalyst-bound-mip") which mip is a first receptor and (2) a solute which is catalytically transformed by a catalyst bound to a mip-containing measurement first surface to produce a detectable signal at said first surface in relation to the amount of catalyst-bound-mip bound to said first surface, wherein contacting of said first surface with said sample and said catalyst-bound-mip results in binding of said catalyst-bound-mip to said first surface in relation to the amount of analyte in said sample,

the improvement which comprises:

having in contact with an assay medium a calibration second surface to which a second receptor for said first receptor is bound in an amount to cause binding of said catalyst-bound-mip and thereby producing a signal at said second surface and determining the presence or amount of said analyte in said sample by comparing the intensity of said signal at said first surface to the intensity of said signal at said second surface.

21. A method according to claim 20, wherein said catalyst is an enzyme.

22. A method according to claim 20, wherein said first receptor is an antibody and said second receptor is anti-(antibody).

23. A device for conducting an assay for the presence of an analyte, which comprises:

a measurement first surface of a porous material,

a calibration second surface of a porous material in close proximity to said first surface,

a member of a specific binding pair non-diffusively bound to said first surface, and

an anti-catalyst non-diffusively bound to said second surface,

wherein said device comprises a plurality of said first surface or a plurality of said second surface or a plurality of said first surface and said second surface.