Internally referenced competitive assays

• US 6,287,875 B1
• Filed: 05/24/2000
• Issued: 09/11/2001
• Est. Priority Date: 05/02/1997
• Status: Expired due to Term

• Current Assignee: Silver Lake Corporation
• Original Assignee: Silver Lake Corporation
• Inventors: Geisberg, Mark S.
• Primary Examiner(s): Le, Long V.
• Assistant Examiner(s): Do, Pensee T.
• Application Number:
  US09/577,635
• Time in Patent Office: 475 Days
• Field of Search: 436/514, 436/518, 436/517, 436/523, 436/526, 436/531, 436/533, 436/544, 436/545, 436/546, 422/55, 422/57, 422/68.1, 422/69, 422/70, 422/82.05, 435/4, 435/7.1, 435/7.5, 435/7-2-, 435/14, 435/25, 435/28, 435/287.1, 435/287.2, 435/288.7, 435/287.9
• US Class Current: 436/518
• CPC Class Codes: G01N 33/54306 Solid-phase reaction mechanisms
• CPC Class Codes: G01N 33/54388 based on lateral flow
• CPC Class Codes: G01N 33/558 using diffusion or migration of antigen or antibody immunochromatographic test strips G01N33/54387

Abstract

The present invention provides internally calibrated competitive assays for use on a solid support. Additionally, the invention provides a method of using such assays.

Claims

1. A device for the detection of at least one analyte in a sample solution, comprising a solid support having:

(a) a particle zone that contains particles containing a first member of an inverse ligand-receptor pair, a first member of a direct ligand-receptor pair, and a signal reagent; and

(b) a first and a second signal zone wherein the first signal zone contains a second member of the inverse ligand-receptor pair and the second signal zone contains a second member of the direct ligand-receptor pair

 

wherein;

the analyte is a member of the inverse ligand-receptor pair or an analog thereof and is not a member of the direct ligand-receptor pair or analog thereof; and

the above elements are arranged in fluid communication, whereby the sample solution suspected of containing the analyte is introduced into the particle zone and then flows through the first and subsequently the second signal zone of each signal area whereby one or more predetermined concentrations of analyte can be discerned from a ratio of signals in the first and second signal zones.

2. A device of claim 1, wherein the particles contain only the first member of the inverse ligand-receptor pair and the signal reagent.

3. A device of claim 1, wherein the signal reagent is a visible particle.

4. A device of claim 1, wherein the signal reagent is a colored latex particle.

5. A device of claim 1, wherein the inverse ligand-receptor pair is an antibody-antigen pair.

6. A device of claim 5, wherein the direct ligand-receptor pair is an antibody and an antibody-binding reagent.

7. A device of claim 1, wherein the direct ligand-receptor pair is avidin and biotin.

8. A device of claim 1, wherein the solid support is in the form of a strip.

9. A device of claim 1, wherein the solid support contains a bibulous material.

10. A device of claim 1, wherein the solid support contains nitrocellulose.

11. A device of claim 1, wherein the solid support contains a non-bibulous material.

12. A device of claim 1, wherein a predetermined concentration of analyte can be discerned from a signal ratio when the signals from the first and second signal zones are approximately equal.

13. A device of claim 1, wherein the total amount of the first member of an inverse ligand-receptor pair in a population of particles is such that from one to three predetermined concentrations of an analyte can be discerned from a signal ratios, the first concentration indicated when the ratio between the first and second signal zones is or approaches infinity, the second concentration when the ratio between the first and second signal zone is approximately one, and the third concentration indicated when the ratio between the first and second signal zones is approximately the inverse of infinity.

14. A device of claim 1, wherein the signal reagent is a colloidal metal particle.

15. A device of claim 1, wherein the signal reagent is an enzyme.