Simultaneous calibration heterogeneous immunoassay

An internally calibrated diagnostic apparatus for determining the presence or amount of an analyte in a sample, said apparatus comprising a support, a measurement first surface of a porous material mounted on said support;

• a calibration second surface of a porous material mounted on said support in close proximity to said first surface;
• a member of a specific binding pair (mip) non-diffusively bound to said first surface;
• and at least one of an enzyme, anti-enzyme or receptor for a receptor for said mip non-diffusively bound to said second surface in an amount such that the difference in the detectable signal between the calibration second surface and the measurement first surface is qualitatively or quantitatively related to the amount of analyte in the sample.

A method for conducting an assay for the presence or amount of an analyte selected from the group consisting of ligands and receptors in a liquid medium, which comprises:

• subjecting an underlying structure comprising measurement and calibration surfaces to the same assay environment whereby a signal resulting from an enzyme on each of said surfaces is generated, said enzyme either being initially bound to said calibration surface or becoming bound to said calibration surface by the intermediacy of specific binding pair complex formation involving a determinant site other than that involved in the binding of the enzyme to said measurement surface, and
• comparing the intensities of signals at said measurement and calibration surfaces to determine the presence or amount of said analyte in said liquid medium.

A method for conducting an assay for the presence or amount of an analyte, which comprises:

• subjecting to the same assay environment (1) a measurement surface to which a catalyst-specific binding pair member ("mip") conjugate becomes bound in relation to the amount of an analyte in a liquid medium and (2) a calibration surface to which an amount of catalyst becomes bound, by the intermediacy of specific binding pair complex formation involving a determinant site other than that involved in the binding of the catalyst-mip conjugate to said measurement surface, that is substantially independent of the amount of analyte in said liquid medium whereby a signal is generated on each of said surfaces, said measurement surface and said calibration surface being on a common support, 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.

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 an enzyme 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 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 adjacent to said first surface a calibration second surface to which a receptor for enzyme catalyst is bound in an amount to cause binding of such catalyst-bound-mip and produce a signal at said second surface and the presence or amount of said analyte in said sample is determined by comparing the intensity of said signal at said first surface to the intensity of said signal at said second surface.

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 (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 adjacent to said first surface on a common underlying support 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 produce a signal at said second surface and the presence or amount of said analyte in said sample is determined by comparing the intensity of said signal at said first surface to the intensity of said signal at said second surface.

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 enzyme catalyst including an enzyme 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 analyte in said sample,
• the improvement which comprises"
• having adjacent to said first surface a calibration second surface to which said enzyme catalyst becomes bound, during said contacting by means of mip complex formation involving anti-enzyme catalyst on said calibration surface, in an amount to produce a signal level at said second surface and said analyte in said sample is determined by comparing the intensity of the signal at said second surface to the intensity of the signal at said first surface.

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 an antibody ("catalyst-bound-antibody") 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-antibody bound to said first surface, wherein contacting of said first surface with said sample and said catalyst-bound-antibody results in binding of said catalyst-bound-antibody to said first surface in proportion to the amount of analyte in said sample,
• the improvement which comprises"
• having adjacent to said first surface a calibration second surface to which said catalyst becomes bound, during said contacting by means of mip complex formation involving an anti-(antibody) on said calibration surface, in an amount to produce a signal level at said second surface, and said analyte in said sample is determined by comparing the intensity of the signal at said second surface to the intensity of the signal at said first surface.

A method for conducting an assay for the presence or amount of an analyte, which comprises:

• subjecting to the same assay environment (1) a measurement surface to which a catalyst-specific binding pair member ("mip") conjugate becomes bound in relation to the amount of an analyte in a liquid medium and (2) a calibration surface having a receptor for an enzyme catalyst to which an amount of enzyme becomes bound that is substantially independent of the amount of analyte in said liquid medium whereby a signal is generated on each of said surfaces 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.

A method for conducting an assay for the presence or amount of an analyte, which comprises:

• subjecting to the same assay environment (1) a measurement surface to which a catalyst-antibody conjugate becomes bound in relation to the amount of an analyte in a liquid medium and (2) a calibration surface having an anti-(antibody) to which an amount of catalyst becomes bound that is substantially independent of the amount of analyte in said liquid medium whereby a signal is generated on each of said surfaces 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.

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 (1) at least one catalyst including a catalyst bound to a mip ("catalyst-bound-mip"), which mip is an antibody, 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 adjacent to said first surface a calibration second surface to which an anti-(antibody) is bound in an amount to cause binding of said catalyst-bound-mip and thereby produce a signal at said second surface and the presence or amount of said analyte in said sample is determined by comparing the intensity of said signal at said first surface to the intensity of said signal at said second surface.