Lateral-flow assay device having flow constrictions

Patent metadata

Field	Value
Publication number	US-10071373-B2
Application number	US-201514817760-A
Country	US
Kind code	B2
Filing date	Aug 4, 2015
Priority date	Aug 8, 2014
Publication date	Sep 11, 2018
Grant date	Sep 11, 2018

Abstract

A lateral-flow assay device includes a substrate having a sample addition zone and a wash addition zone downstream thereof along a fluid flow path through which a sample flows. The fluid flow path is configured to receive a wash fluid in the wash addition zone. A hydrophilic surface is arranged in the wash addition zone. Flow constriction(s) are spaced apart from the fluid flow path and arranged to define, with the hydrophilic surface, a reservoir configured to retain the wash fluid by formation of a meniscus between the hydrophilic surface and the flow constriction(s). The fluid flow path draws the wash fluid from the reservoir by capillary pressure. Apparatus for analyzing a fluidic sample and methods of displacing a fluidic sample in a fluid flow path of an assay device are also described.

First claim

The invention claimed is:

1. A lateral-flow assay device comprising:
a) a substrate having a top surface including a sample addition zone and a wash addition zone disposed along a fluid flow path through which a sample flows under capillary action in a downstream direction away from the sample addition zone and towards the wash addition zone, wherein the fluid flow path is defined by a plurality of projections extending from the top surface of the substrate, the plurality of projections having a height, diameter and center to center spacing that creates lateral capillary force to an applied liquid and in which a wash fluid can be added to the device in the wash addition zone;
b) at least one hydrophilic surface arranged in the wash addition zone; and
c) flow constriction(s) including a plurality of spaced grooves formed in the top surface of the substrate that are spaced apart from and form an arcuate path around the fluid flow path of the wash addition zone and arranged to define, with the at least one hydrophilic surface, a reservoir configured to retain the wash fluid by formation of a meniscus between the at least one hydrophilic surface and the one or more flow constriction(s) in which an outer edge of the meniscus latches to an edge of one of the grooves; and in which the plurality of the projections of the fluid flow path draw wash fluid from the defined reservoir, which is in fluid contact with the projections.

2. The lateral-flow assay device as recited in claim 1 , wherein the grooves are disposed about a reference point along a centerline of the fluid flow path extending through the wash addition zone.

3. The lateral-flow assay device as recited in claim 1 , including a plurality of the flow constriction(s), each of the flow constrictions including groove(s) formed in the hydrophilic surface, said groove(s) being arranged along respective arcuate paths about the centerline of the fluid flow path.

4. The lateral-flow assay device as recited in claim 1 , wherein at least one said groove has a substantially rectangular cross-section.

5. The lateral-flow assay device as recited in claim 1 , said flow constriction(s) including at least three spaced-apart grooves formed in the top surface of the substrate.

6. The lateral-flow assay device as recited in claim 1 , wherein said at least one groove is configured as a segment of a spiral.

7. The lateral-flow assay device as recited in claim 1 , further including a cover arranged over the substrate, the cover including the at least one hydrophilic surface facing the substrate and an aperture defining a wash port at least partly aligned with the wash addition zone that receives the wash fluid, in which the flow constrictions further comprise a first cover flow constriction including a protrusion extending from the cover towards the substrate proximate the aperture.

8. The lateral-flow assay device as recited in claim 7 , wherein the first cover flow constriction includes a lip of the aperture protruding to a first predetermined distance from the substrate.

9. The lateral-flow assay device as recited in claim 8 , wherein a second cover flow constriction includes a protrusion extending to a second predetermined distance from the substrate.

10. The lateral-flow assay device as recited in claim 9 , wherein the second predetermined distance is greater than the first predetermined distance.

11. The lateral-flow assay device as recited in claim 9 , wherein the second cover flow constriction is arranged outside the aperture.

12. The lateral-flow assay device as recited in claim 8 , wherein the lip of the aperture is substantially annular in shape.

13. The lateral-flow assay device as recited in claim 8 , wherein the aperture and the lip of the aperture are coaxial to one another.

14. The lateral-flow assay device as recited in claim 8 , wherein the aperture and the lip of the aperture are axially offset from one another.

15. The lateral-flow assay device as recited in claim 7 , wherein the first cover flow constriction is shaped as a convex closed figure.

16. The lateral-flow assay device as recited in claim 7 , wherein the first cover flow constriction includes a proximal edge and a distal edge defined with respect to the fluid flow path wherein the distal edge is defined by a curve which is sharper than the curve defining the proximal edge.

17. The lateral-flow assay device as recited in claim 1 , further including a cover arranged over the substrate having at least one cover flow constriction and in which the at least one cover flow constriction comprises a nozzle extending from the cover towards the substrate, defining a wash port at least partly aligned with the wash addition zone, for receiving the wash fluid.

18. The lateral-flow assay device as recited in claim 17 , at least one said flow constriction comprising an annulus arranged around the nozzle and extending a smaller distance from the cover than does the nozzle.

19. The lateral-flow assay device as recited in claim 17 , at least one said flow constriction comprising an annulus arranged around the nozzle and extending substantially the same distance from the cover as does the nozzle.

20. The lateral-flow assay device as recited in claim 17 , wherein the at least one said cover flow constriction comprises an annulus arranged around the nozzle and extending a larger distance from the cover than does the nozzle.

21. The lateral-flow assay device as recited in claim 20 , wherein the at least one said cover flow constriction further comprises a plurality of protrusions arranged symmetrically about the annulus and spaced apart from the annulus.

22. The lateral-flow assay device as recited in claim 17 , wherein the nozzle has a surface defined by a plurality of annular steps facing the substrate.

23. The lateral-flow assay device as recited in claim 17 , in which the at least one said cover flow constriction comprises a protrusion spaced apart from the nozzle.

24. The lateral-flow assay device as recited in claim 17 , wherein the at least one said cover flow constriction comprises a plurality of protrusions arranged substantially about the nozzle and spaced apart from the nozzle.

25. The lateral-flow assay device as recited in claim 1 , further including at least one detection zone disposed along the fluid flow path downstream of the sample addition zone and the wash addition zone, the at least one detection zone including a detection material responsive to an analyte of the sample to produce a detectable signal.

Assignees

• Ortho Clinical Diagnostics Inc

Inventors

• Ding Zhong
• Scalice Edward R
• Salotto Daniel P

Classifications

• B01L2300/161

  Control and use of surface tension forces, e.g. hydrophobic, hydrophilic · CPC title

• B01L2300/0867

  Multiple inlets and one sample wells, e.g. mixing, dilution · CPC title

• B01L3/5023 Primary

  with a sample being transported to, and subsequently stored in an absorbent for analysis · CPC title

• B01L2300/041

  Connecting closures to device or container · CPC title

• B01L2400/0406

  capillary forces · CPC title