POC test system and method

1. A method of fabricating a test cassette for the detection of at least one analyte from a sample fluid, comprising:

a) providing a test cassette structure having a first sample chamber and a second sample chamber separated by a carrier having at least two surfaces comprising a front side and a rear side, wherein the front side of the carrier points towards the first sample chamber and the rear side of the carrier points towards the second sample chamber, and

b) fixing at least one receptor molecule on the front side of the carrier,

c) forming at least one free volume over each of the front side and the rear side of the carrier and delimiting the free volume in each case by a chamber wall,

d) providing the first sample chamber with at least a first opening and a second opening, wherein the sample fluid flows through the first opening along a flow gradient over the front side of the carrier to the second opening distanced from the carrier,

e) providing the second sample chamber with at least a first opening and a second opening, wherein the sample fluid flows through the first opening of the second sample chamber from the first sample chamber along a flow gradient over the rear side of the carrier,

f) interconnecting the second opening of the first sample chamber and the first opening of the second sample chamber by a channel.

2. The method of fabricating according to claim 1 , comprising using as the carrier a carrier which is partially permeable to the sample fluid.

3. The method of fabricating according to claim 1 , including using as the channel a channel which is smaller in diameter than the diameter of the first sample chamber and the second sample chamber or of the free volume over the front side and the rear side of the carrier.

4. The method of fabricating according to claim 1 , comprising surrounding the channel around a fastening element of the carrier with the channel having a round bore.

5. The method of fabricating according to claim 1 , including communicating the second opening for the second chamber for the discharge from the second sample chamber by a further channel to a third chamber, wherein this third chamber

a) partially contains an absorbent material and

b) contains a vent.

6. The method of fabricating according to claim 1 , wherein the test cassette structure is fabricated by injection moulding three components comprising an upper half-shell and a middle part and a lower half-shell, locating at least one film between at least one of the upper half-shell or the lower half-shell and the middle part, providing the middle part with at least one cutout and least two tabs for receiving the carrier, locating a further film between the middle part and the other of the upper half-shell and the lower half-shell, and interconnecting the three components by laser welding.

7. The method of fabricating according to claim 1 , including selecting a distance of the front or rear side of the carrier to the chamber wall which is at least 10 μm.

8. The method of fabricating according to claim 7 , wherein the distance selected is 80 μm to 350 μm.

9. The method of fabricating according to claim 1 , comprising forming the carrier of a solid material, completely or partially formed of a gel, sieve, permeable or semi-permeable membrane.

10. The method of fabricating according to claim 1 , including fixing at least one receptor molecule on the rear side of the carrier.

11. The method of fabricating according to claim 1 , characterised in that using as the carrier a carrier having a length of 40-60 mm, a width of 2.0-10 mm, and an inlet diameter 0.15 mm to 0.45.

12. The method of fabricating according to claim 1 , characterised in that the first and second sample chambers are part of a plurality of sample chambers, and supplying the sample fluid to the plurality of sample chambers in parallel from a sample chamber with at least one sample fluid.

13. The method of fabricating according to claim 4 , including using a transverse strut as the fastening element.

14. The method of fabricating according to claim 5 , comprising using as the vent an additional channel with at least one bend or at least one additional chamber.

15. The method of fabricating according to claim 6 , comprising welding by laser mask welding.

16. The method of fabricating according to claim 7 , comprising selecting as the distance a distance which is up to 1,500 μm.

17. The method of fabricating according to claim 8 , comprising selecting as the distance a distance which is 120 μm to 200 μm, and selecting different distances of the front side and the rear side of the carrier.