Point-of-care test system and method for applying a sample

Abstract

The present invention relates to a test system or assay system (detection system) and to a test method, preferably in use in the point-of-care (PoC) field.

Claims

1. A test method comprising: a) applying a sample fluid in a sample channel of a test system, wherein the sample channel leads to a discharge area and a membrane, wherein the membrane comprises a first surface having at least one test reagent fixed thereon and a second surface formed on the reverse side of the first surface, wherein the second surface is facing the discharge area and has a wetting point, wherein the sample channel comprises a narrowed area connected to a widened area at its end that faces the second surface through a discharge opening, and wherein the widened area ends in the discharge area with a discharge opening edge; b) applying pressure to the sample channel so that the sample fluid passes through the discharge opening from the narrowed area and forms a drop that adheres to the discharge opening; c) enlarging the drop by applying pressure to the sample channel until the drop contacts the wetting point on the second surface; and d) allowing the sample fluid to penetrate from the second surface toward the first surface to react with the at least one test reagent.

2. The test method of claim 1, wherein the edge of the discharge opening is hydrophobic.

3. The test method of claim 1, wherein the drop at least partially wets the widened area.

4. The test method of claim 1, wherein the discharge opening edge is spaced from the second surface by 0.001 mm to 15 mm.

5. The test method of claim 1, wherein the discharge opening edge has a diameter of between 0.015 and 15 mm.

6. The test method of claim 1, wherein the widened area has a depth of 0.001 mm to 2 mm.

7. The test method of claim 1, wherein the second surface ends on the discharge opening edge of the widened area or lies at least partially on the widened area or beside the widened area.

8. The test method of claim 1, wherein the widened area is conical or concave in the form of a plate or a spherical segment.

9. The test method of claim 1, wherein at least one additional reagent is supplied to the sample channel.

10. The test method of claim 1, wherein the first surface and/or the second surface consists of a porous, permeable, semipermeable, or dialysis membrane.

11. The test method of claim 1, wherein a point of passage is located on the first surface and is free of the at least one test reagent.

12. The test method of claim 1, wherein the first surface and the second surface each forms a cavity independently of one another.

13. The test method of claim 1, wherein the narrowed area has a reduction in cross-sectional area of more than 1%.

14. The test method of claim 1, wherein the sample fluid reacts with the at least one test reagent in a binding assay.

15. The test method of claim 1, wherein the sample fluid is whole blood, serum, saliva, tears, urine, secretions, or cranial fluid.

Description

DESCRIPTION OF THE FIGURES

(1) FIG. 1(a) shows a possible configuration consisting of a second cavity (1), a membrane (2), a widened area (3), a surface (4) of the widened area (3), a narrowed area or restrictor (5), a substrate (6), an assay site (7) with test reagent and a sample channel (8) and discharge area (9).

(2) FIG. 1(b) shows that when the membrane does not lie on the discharge area (9) or is inclined at an angle, the arrangement ensures a nearly uniform wetting (inclined position of the membrane in the drawing is exaggerated for purposes of clarity).

(3) FIG. 2 illustrates the wetting process according to the invention. The block arrows at the bottom of the drawing indicate the direction of expansion of pressure in the fluid. (Left) The sample fluid exits the restrictor and forms a drop in the widened area. (Center) The drop grows and comes into contact with the membrane at wetting point (10). (Right) The sample fluid spreads in the membrane, in the direction (11) of the assay sites.

(4) FIG. 3 shows different forms of the narrowed area or restrictor, in a longitudinal cross-section. The widened areas are each illustrated as trapezoids. The form on the far right side is a trumpet-shaped widened area.

(5) FIG. 4(a) illustrates the distribution of the sample fluid in the sample channels, which fluid is conducted from a shared fill port (12) via cross connectors to the restrictor (5) and to the connected widened areas.

(6) FIG. 4(b) schematically illustrates the plane of infeed of the washing solution via the shared fill port (12); with the second cavities (1), in which the membranes lie; the indicated widened areas (3) on the underside of the membrane (second surface), along with the assay sites (7) to a waste receptacle (13).