POC TEST SYSTEM AND METHOD

Abstract

The present invention relates to a test system or an assay system (detection system) and test method preferably for use in the Point-of-Care (PoC) field.

Claims

1.-19. (canceled)

20. A kit consisting of a test system having two sample chambers, which are separated by a carrier having at least two surfaces, containing a carrier together with fixed receptor molecules for carrying out a binding assay with an inlet and outlet, wherein a free space exists to the chamber ceiling and chamber base, and optionally a further auxiliary chamber, which is fluidically connected to the sample chamber, together with a means for pressure application and further auxiliaries and additives.

21. The kit as claimed in claim 20 which comprises the kit is used for the detection of at least one analyte (substances) from a sample fluid in human, veterinary medical or plant diagnostics, food diagnostics, environment diagnostics, forensic diagnostics, pharmacology, toxicology, in allergies, autoimmune or metabolic diseases, infectious diseases, sexually transmitted diseases, food intolerances, parasitic diseases, determination of small molecules such as drugs, medications or metabolic products, cell mediators, tissue typing, sort typing, food typing, antigen typing, epitope typing and DNA or RNA detection.

22. A test method for the detection of at least one analyte from a sample fluid comprising two sample chambers, which are separated by a carrier having at least two surfaces, wherein a front side of the carrier points towards the first sample chamber and a rear side of the carrier points towards the second sample chamber, and a) at least one receptor molecule is fixed on the front side of a carrier, b) at least one free volume is formed over each of the front side and rear side of the carrier and is delimited in each case by a chamber wall, c) the first sample chamber has at least two openings, wherein a sample fluid flows through a first opening along a flow gradient over the front side of the carrier to the second opening distanced from the carrier, d) the second sample chamber has at least two openings, wherein the sample fluid flows through a first opening from the first sample chamber along a flow gradient over the rear side of the carrier and preferably in a direction opposite the flow on the front side of the carrier to the second opening, e) the second opening of the first sample chamber and the first opening of the second sample chamber are interconnected by a channel, f) the second opening of the second sample chamber enables the discharge of the fluid, g) the free volumes from b.) are formed at least partially with a fluid column, h) wherein the flow gradient along the front and rear side of the carrier is provided by means of pressure application and entrains the fluid column from g.).

23. A test method for the detection of at least one analyte from a sample fluid, comprising two sample chambers, which are separated by a carrier having at least two surfaces, wherein a front side of the carrier points towards the first sample chamber and a rear side of the carrier points towards the second sample chamber, and a) at least one receptor molecule is fixed on the front side of a carrier, b) at least one free volume is formed over each of the front side and rear side of the carrier and is delimited in each case by a chamber wall, c) the sample fluid is divided into the sample chambers via a channel branching into two channels, wherein each leads into a respective one of the two sample chambers, wherein the sample fluid flows in each case through a first opening along a flow gradient over the front and rear side of the carrier to a second opening distanced from the carrier, d) the second opening in each of the sample chambers transitions in each case into at least one channel, which enables the discharge from the sample chambers, e) the free volumes from b.) are formed at least in part with a fluid column, f) wherein the flow gradient along the front and rear side of the carrier is produced by means of pressure application and entrains the fluid column from e.).

24. The test method for the detection of at least one analyte from a sample fluid according to claim 23, comprising two sample chambers, which are separated by a carrier having at least two surfaces, wherein the carrier is partially permeable to a sample fluid.

25. The test method according to claim 23, wherein the channel is smaller in diameter than the diameter of the sample chamber or of the free volume.

26. The test method according to o claim 23, wherein the channel surrounds a fastening element, of the carrier and has a round bore.

27. The test method according to claim 23, wherein the discharge from the second sample chamber is connected by a channel to a further chamber, wherein this third chamber a) partially contains an absorbent material and b) contains a vent or at least one further chamber.

28. The test method according to claim 23, wherein the discharge from the second sample chamber is connected by a channel to a further chamber, wherein this third chamber a) partially contains an absorbent material and b) contains a vent, as a channel with at least one bend or at least one further chamber.

29. The test method according to claim 23, wherein the test cassette consists of three components fabricated by injection moulding (half-shell, middle part, and half-shell), wherein at least one film is located between at least one half-shell and the middle part and is provided with at least one cutout and least two tabs for receiving carriers, wherein a further film is located between the middle part and the second half-shell and these components are interconnected by laser welding and in particular by laser mask welding.

30. The test method according to claim 23, wherein the distance of the front or rear side of the carrier to the chamber wall is 10 μm or more.

31. The test method according to claim 28, wherein the distance is 80 μm to 350 μm, wherein the distances of the front and rear side of the carrier may be different.

32. The test method according to claim 23, wherein the carrier consists of a solid material, completely or partially formed of a gel-like, porous, sieve-like, permeable or semi-permeable membrane, dialysis membrane.

33. The test method according to claim 23, wherein at least one receptor molecule is fixed on a second surface of a carrier.

34. The test method according to claim 23, wherein the flow gradient is guided a.) in parallel on the first and second surface of the carrier or is guided b.) antiparallel on the first and second surface of the carrier.

35. The test method according to claim 23, wherein the sample fluid is a biological or non-biological fluid, in particular whole blood, half-blood, plasma, serum, saliva, tear fluid, urine, secretion, brain fluid or processed forms of such fluids, or bacteria-containing solutions, or active ingredients.

36. The test method according to claim 23, characterised in that the pressure application occurs by means of overpressure or negative pressure.

37. The test method according to claim 23, characterised in that, with an input of a sample fluid inclusive of 300 μl sample diluent, from 340-540 μl for plasma and 480-520 μl for blood as sample fluid, the sample chamber is formed as follows: length of the carrier 40-60 mm, width of the carrier 2.0-10 mm, inlet diameter 0.15 mm to 0.45.

38. The test method according to claim 23, characterised in that a plurality of sample chambers are supplied in parallel from a sample chamber with at least one sample fluid.

39. The test method according to claim 23, characterised in that antibodies are used for the detection of the analyte.

Description

EXAMPLES AND FIGURES

[0111] These examples serve exclusively for explanation of the invention and do not limit the invention to these examples.

Example 1: Test Protocol for Allergy Test

[0112] Preparation

[0113] Bring test box with test tubes and test cassette (kit containing sample chamber) and also the patient sample to room temperature (18-25° C.).

[0114] Have ready timer, disposable gloves, container for solid waste and pen.

[0115] Remove test cassette and syringe.

[0116] All incubations take place at room temperature.

[0117] Reinsert, upright, the reagent tubes inserted in the test box (kit), either prior to or following the test procedure, into the correspondingly coloured holding devices at the upper edge of the box.

[0118] 1.1. Sample Introduction:

[0119] Open sample tubes (red cover) containing previously introduced sample and transfer the content completely and bubble-free into the test cassette by means of the syringe. For this purpose insert the syringe into the sample opening and inject the content quickly.

[0120] Set down the test cassette on a flat support and incubate for 4 minutes.

[0121] 1.2. Addition of the Test Solution:

[0122] Quickly inject the content of the conjugate solution (yellow cover) as described before (section 10.1.) into the inlet of the test cassette with the aid of the syringe and incubate this, set down, for 8 minutes.

[0123] 1.3. Washing:

[0124] Open the first test tube containing washing solution (blue cover) and quickly inject the content as previously described into the inlet of the test cassette. Then immediately quickly inject the content of the second test tube containing washing solution (blue cover). No incubation is necessary.

[0125] 1.4. Development:

[0126] Open the first tube containing colour substrate (white cover) and quickly inject the content into the inlet of the test cassette. Then immediately open the second test tube containing colour substrate (white cover), inject the content bubble-free into the inlet of the test cassette and incubate this, set down, for 8 minutes.

[0127] During the development, 2 parallel reference lines of different intensity and possibly additionally a central test line are visible in each test field.

[0128] 1.5. Stopping:

[0129] Open test tubes containing stop solution (green cover) and inject the content into the inlet of the test cassette. Note: The test results are stable for at least 12 hours and can be read off during this time.

Example 2: Test Chamber (Sample Chamber)

[0130] Dimensions for the membrane and values of the distances thereof from other elements of the device will be specified hereinafter. Here, it should be noted that all dimensions/values are specified for the dry state of the membrane and that a possible deflection of the membrane or surface unevennesses or a potential warping of the injection-moulded parts is not taken into consideration. In the moist state the membrane may swell or deflect and may thus have a modified thickness and modified distances from other components.

[0131] A (reinforced) nitrocellulose membrane 140 μm thick is cut to a size of 50.5 mm×6.3 mm. The resultant membrane strip is placed on a film provided with a cutout, such that the strip completely covers the cutout and is clamped at the end sides thereof in each case beneath a tab, said tabs being located at the end-side ends of the cutout in the film. The film is clamped with the membrane strip between two injection-moulded half-shells, which together with the film and the membrane strip form both sample chambers according to FIGS. 1b and 2, of which the width is 3.5 mm. The total volume of the membrane is thus 44.5 μl, and that of the free membrane is 24.7 μl. The distance of the membrane upper side to the substantially planar inner side of the upper chamber wall is 170 μm, and that from the membrane lower side to the substantially planar lower chamber wall of the half-shell is 150 μm. The volume of the upper chamber is 30.04 μl, and that of the lower chamber is 26.51 μl. The cross section of the unclamped part of the membrane is 0.49 mm.sup.2, and that of the chamber is 1.62 mm.sup.2.

[0132] The chamber is provided with an inlet opening in the first sample chamber in the vicinity of an end of the membrane, which inlet opening has a cross section of 0.3 mm.sup.2, and with an outlet opening in the second sample chamber in the vicinity of the membrane with a cross section of 1.2 mm.sup.2.

[0133] In the test device 4×2 chambers are formed in parallel, such that the entire membrane volume is 98.98 μl, that of the first chambers without inflow and outflow is 120.19 μl, and that of the second chambers is 106.05 μl. They are filled simultaneously through a single access (sample channel), which fans out into 4 channels, each of which is connected to a first chamber. The outlet openings in turn converge into a single channel, which is connected to a waste volume integrated in the test device, in which waste volume absorbent material is accommodated. The absorbent material is not fluidically connected to any membrane, and therefore the suction effect is limited to free fluid that passes into the waste. The test device has windows, through which the regions of the test strips charged with reagent can be observed.

[0134] An opaque film provided with cutouts is bonded to the test cassette. The cutouts serve as windows, through each of which windows the measuring fields each provided for a respective allergen can be viewed or read out using an optical reader. The webs between the windows, which are lined up along a carrier, are kept as narrow as possible, for example 2 mm or less. The webs perpendicularly thereto, from carrier to carrier are wider, such that there is enough space thereon for printed-out information regarding the individual measuring fields. This information may include numbers, acronyms or an entire term, for example designating the allergen.

[0135] In a test the following substances and quantities are added in the test device in accordance with protocol 1:

TABLE-US-00001 1) sample together with sample diluent 380 μl 2) washing bugger per procedure 1,000 μl 3) substrate solution per procedure (flushing twice) 2 × 800 μl 4) antibody/conjugate solution 1 800 μl 5) antibody/conjugate solution 2 800 μl 6) stop buffer 1,000 ul

[0136] The volume of each individual test component is greater than the volume of the membranes (100 μl).

DESCRIPTION OF THE FIGURES

[0137] FIG. 1a: longitudinal section through a test cassette with both sample chambers, in which fluid is guided at both surfaces of the carrier (1) (front side and rear side) in the flow (3) in parallel. The cassette is pressurised through the inlet opening (5), such that the fluid flows from there to the outlet opening and from there through a further channel to the waste (4) (auxiliary chamber (supra)).

[0138] FIG. 1b: longitudinal section through a sample chamber, in which fluid flows at the end of the carrier (1) through a further channel and is conveyed to the rear side of the carrier and flows at the second surface (rear side) antiparallel to the first surface.

[0139] FIG. 2: Plan view of a sample chamber. A number of carriers may be arranged in parallel in a cassette. For this purpose, the flow may be divided or the carriers may be located jointly in one cavity.

[0140] FIG. 3: Detailed longitudinal section of an embodiment, not shown to scale. The solutions are introduced through the inlet opening (5) and flow (3) over the front side of the fixed carrier (1), on which test reagents (2) are located. From there, the solutions pass via a further channel at the other end of the carrier to the rear side of the carrier and flow over this to an outlet opening. An additional channel conveys the fluids to the waste (4), which preferably contains an absorbent material. The chamber for the waste is connected to the outside world via a vent. This vent may be provided with a chicane and further chambers, so as to prevent a leakage of the waste.

[0141] FIG. 4: Immunoassay with three identical membranes as solid phase, performed at the same time in accordance with the protocol from Example 1. In tracks 1 and 2 fluid flows over the membranes from both sides, and in track 3 fluid flows over the upper side only. Identical reagents and volumes were used in all tracks.

[0142] FIG. 5: Longitudinal section as exploded drawing to illustrate the layered structure of the test cassette. The films are located in each case between an injection-moulded half-shell, which is transparent in some regions, and a middle part, which likewise is injection moulded. The laser welds, through the half-shells, the film to the half-shell and middle part, and also welds the half-shells and middle part to one another.

[0143] FIG. 6: Detailed plan view of the carrier, not true to scale. The carrier is clamped beneath the end-side tabs of the film and covers the cutout in the film

[0144] FIG. 7: Cross section through a test cassette, not true to scale. The carrier is fixed at the edges of the sample chambers. Any curvature of the carrier in the transverse direction is shown heavily exaggerated. If a curvature is present or is produced after wetting, the carrier is preferably inserted such that the curvature is formed towards the front side.