Hybrid phase lateral flow assay

• US 20050227371A1
• Filed: 03/23/2005
• Published: 10/13/2005
• Est. Priority Date: 03/23/2004
• Status: Active Grant

• Current Assignee: Quidel Corporation
• Original Assignee: Quidel Corporation
• Inventors: Gokhan, Cem
• Granted Patent: US 7,632,687 B2
• Time in Patent Office: Days
• US Class Current: 436/514
• CPC Class Codes: G01N 2500/10 involving cells
• CPC Class Codes: G01N 33/54386 Analytical elements
• 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
• CPC Class Codes: Y10S 435/805 Test papers
• CPC Class Codes: Y10S 435/823 Acetobacter
• CPC Class Codes: Y10S 436/807 Apparatus included in process claim, e.g. physical support structures
• CPC Class Codes: Y10S 436/823 Immunogenic carrier or carrier per se
• CPC Class Codes: Y10T 436/25125 Digestion or removing interfering materials

Abstract

The invention relates to devices for performing single step assays for the determination of the presence or absence of an analyte in a liquid sample, and methods of determining the presence or absence of such analytes using such devices. Devices disclosed comprise a labeled analyte-binding reagent reversibly-immobilized on a non-porous solid material, which solid material is in physical contact with a dry porous carrier bearing an immobilized analyte-binding reagent. Also provided are quantitative assay devices.

Claims

1. An analytical device for the single-step determination of the presence of an analyte in a liquid sample comprising a test strip comprising:

a non-porous solid surface comprising, in a reversible immobilization zone, a reversibly immobilized labeled reagent that binds said analyte to form a complex, and

a porous carrier comprising, in a detection zone, an immobilized reagent that binds said complex in the presence of analyte to generate a detectable signal, wherein said porous carrier is in contact with said non-porous surface.

2. The device of claim 1 further comprising a sink, distal to and in contact with said porous carrier, said sink capable of absorbing excess liquid sample after said liquid sample traverses said test strip.

3. The device of claim 1 which further comprises a porous sample application member.

4. The device of claim 3 wherein said porous sample application member is in contact with at least a portion of said non-porous solid surface.

5. The device of claim 1, wherein said porous carrier further comprises, a control site separate from and distal to the detection zone.

6. The device of claim 5 wherein said reversible immobilization zone comprises a plurality of labeled reagents.

7. The device of claim 6 wherein each of said plurality of labeled reagents binds a different analyte.

8. The device of claim 6 wherein said porous carrier comprises, in one or more detection zones, a plurality of immobilized binding reagents.

9. The device of claim 8 wherein each of said plurality of immobilized binding reagents is located in a spatially distinct detection zone and each binds a different analyte to generate a detectable signal.

10. The device of claim 1 which further comprises a plurality of said test strip assemblies, each assembly bearing reagents that identify the presence of one or more different analytes.

11. The device of claim 1 which further comprises a second piece of non-porous solid surface, said surface sized such that when said second piece of non-porous solid material is placed over said first non-porous surface, no edge of said first non-porous surface extends beyond an edge of said second non-porous surface, wherein said second piece of non-porous solid surface is positioned parallel to said first non-porous surface, said second piece having an aperture through which sample is introduced, and wherein said second piece is positioned such that said aperture is located upstream of said reversible immobilization zone and provides protection to said first non-porous surface from undesired wetting during sample application.

12. The device of claim 1 further comprising a sample reservoir, proximal to said reversible immobilization zone and formed from a continuation of said non-porous solid material or from the juxtaposition of a second piece of non-porous solid surface with said first piece of non-porous solid surface.

13. The device of claim 1 which further comprise a housing.

14. The device of claim 13 wherein at least one element of said housing comprises the non-porous solid surface.

15. The device of claim 13 which further comprises a sink, distal to and in contact with said porous carrier, said sink capable of absorbing excess liquid sample after said liquid sample traverses said test strip wherein said housing comprises an aperture to permit evaporation from said sink.

16. The device of claim 13 wherein said housing comprises an aperture through which sample is applied and an aperture through which a result is observed.

17. The device of claim 16 wherein said observation aperture is covered by a non-porous transparent material.

18. The device of claim 1 wherein said reversible immobilization zone is open on at least three sides.

19. The device of claim 1 wherein liquid sample applied to said non-porous solid surface mobilizes said reversibly immobilized labeled reagent, whereupon analyte in said liquid sample is permitted to bind said labeled reagent to form a complex which, together with sample liquid, flows into said porous carrier, wherein said immobilized reagent binds said complex, thereby generating a detectable signal indicative of the presence of said analyte in said sample.

20. The device of claim 1 wherein the detection zone is at the proximal end of the porous carrier.

21. The device of claim 1 wherein the label is a colloid, a dye, a latex particle, an enzyme or a fluorophore.

22. The device of claim 1 wherein the non-porous solid surface is glass, a metal, a ceramic, a high surface density plastic, a polymer or a fluoropolymer resin or polyester film.

23. The device of claim 1 wherein the porous carrier is nitrocellulose or paper.

26. A method of detecting an analyte, the method comprising

a) contacting a liquid sample to be tested for said analyte with the analytical device of claim 1;

and

b) permitting said liquid sample to traverse said test strip such that said reversibly immobilized labeled reagent is mobilized by the sample and flows to said detection zone, wherein, if analyte is present in said liquid sample, a detectable signal is generated indicative of the presence of said analyte.

24. An analytical device for the single-step determination of the presence of an analyte in a liquid sample comprising a test strip comprising:

a) a first piece of non-porous solid surface comprising, in a reversible immobilization zone, a reversibly immobilized labeled reagent that binds said analyte to form a complex;

b) a porous carrier comprising, in a detection zone, an immobilized reagent that binds said complex, wherein said porous carrier is in contact with said non-porous solid surface; and

c) a second piece of non-porous solid surface placed over (a) and (b).

25. The device of claim 24 wherein, rather than being reversibly immobilized upon the first piece of non-porous solid material, said labeled reagent is reversibly immobilized in a reversible immobilization zone on the surface of said second piece of non-porous solid material that faces said first piece of non-porous material, so that the first piece of non-porous solid material is on the bottom and the labeled reagent is reversibly immobilized on the underside of said second piece.

27. A method of detecting an analyte, the method comprising a) contacting a liquid sample to be tested for said analyte with the analytical device of claim 24;

and

b) permitting said liquid sample to traverse said test strip such that said reversibly immobilized labeled reagent is mobilized by the sample and flows to said detection zone, wherein, if analyte is present in said liquid sample, a detectable signal is generated indicative of the presence of said analyte.

28. A device for the single step quantitative measurement of an analyte in a liquid sample, the device comprising:

a) a piece of non-porous solid surface comprising, in an immobilization zone, a reversibly immobilized labeled reagent that binds said analyte to form a complex; and

b) a porous carrier comprising a binding reagent and being in contact with said non-porous solid surface, wherein said binding reagent is applied to and immobilized in a detection zone having a longitudinal axis parallel to a flow of a liquid sample, wherein when said liquid sample comprises the analyte, the binding results in a signal, and wherein the distance from the point at which said liquid sample entered said detection zone to the furthest point in said detection zone at which said signal is detected above background is indicative of the amount of analyte present in said sample.

29. The device of claim 28 wherein said detection area is at least 1.5 times as long as it is wide.

30. The device of claim 28 wherein said detection area extends over at least 50% of the length of said porous carrier.

31. The device of claim 28 wherein said detection area extends over the full length of said porous carrier.

32. A method of detecting an analyte, the method comprising

a) contacting a liquid sample to be tested for said analyte with the analytical device of claim 28;

and

b) permitting said liquid sample to traverse said test strip such that said reversibly immobilized labeled reagent is mobilized by the sample and flows to said detection zone, wherein, if analyte is present in said liquid sample, a detectable signal is generated indicative of the presence or quantity of said analyte.

33. An analytical device for the determination of an analyte in a liquid sample, comprising a test strip comprising:

a non-porous solid surface comprising, in a reversible immobilization zone, a reversibly immobilized reagent able to be mobilized with the passing liquid sample; and

a porous carrier comprising, in a detection zone, an immobilized reagent that generates a detectable signal in the presence or absence of analyte, wherein said porous carrier is in contact with said non-porous surface.

34. An analytical device for the single-step determination of the presence or absence of an analyte in a liquid sample comprising a test strip comprising:

a non-porous solid surface comprising, in a reversible immobilization zone, a reversibly immobilized labeled reagent, that competes with said analyte for binding sites present in the detection zone, and

a porous carrier comprising, in a detection zone, an immobilized reagent that binds said labeled reagent and analyte in a liquid sample, wherein the absence of analyte generates a detectable signal, wherein said porous carrier is in contact with said non-porous surface.

35. A method of detecting an analyte, the method comprising

a) contacting a liquid sample to be tested for said analyte with the analytical device of claim 34;

and

b) permitting said liquid sample to traverse said test strip such that said reversibly immobilized labeled reagent is mobilized by the sample and flows to said detection zone, wherein, analyte present in said liquid sample will compete for binding sites in the detection zone with said labeled reagent, and a detectable signal is generated indicative of the absence of said analyte.