Assay device having a wash port
A test element for an assay includes: a cartridge having a housing which includes a priming pad capable of containing a liquid fluid, a wash port having an opening in the housing, and an opening for directly or indirectly applying a sample; and an assay device positioned within the cartridge in fluid communication with the wash port containing an analytical reagent.
1. A test element for an assay comprising:
a cartridge having a housing including an outer surface, the housing comprising
a priming pad open to the outer surface and capable of containing a liquid fluid;
a wash port having an opening in the outer surface on a same side of the housing as the priming pad; and
an opening for directly or indirectly applying a sample; and
an assay device positioned within the cartridge in fluid communication with the wash port containing an analytical reagent,
wherein the priming pad is fluidically isolated from the wash port and the assay device, and
wherein the priming pad is capable of retaining the liquid fluid such that the liquid fluid will not affect an assay result of the sample applied at the opening of the cartridge.
2. A test element as claimed in claim 1 , wherein the assay device is a lateral flow assay device.
3. A test element as claimed in claim 1 , wherein the priming pad comprises a bibulous material capable of absorbing a liquid fluid.
4. A test element as claimed in claim 1 , wherein the wash port comprises a material capable of supporting capillary flow.
5. A test element as claimed in claim 4 , further comprising a dried reagent on the material capable of supporting capillary flow.
6. A test element as claimed in claim 3 , wherein the material capable of supporting capillary flow is a bibulous material.
7. A element as claimed in claim 1 , wherein the wash port comprises two or more wash ports.
8. A test element as claimed in claim 2 , wherein the lateral flow assay device comprises:
a liquid sample addition zone;
a reagent zone downstream and in fluid communication with the sample addition zone containing a reagent material;
a detection zone in fluid communication with the reagent zone having capture elements bound thereto; and
a wicking zone in fluid communication with the detection zone having a capacity to receive liquid sample flowing from the detection zone,
wherein the sample addition zone, the reagent zone, the detection zone and the wicking zone define a fluid flow path, and
further comprising a reagent addition zone along and in fluid communication with the fluid flow path downstream of the sample addition zone and upstream of the detection zone.
9. An assay device as claimed in claim 8 , where at least a part of the fluid flow path has a substrate surface and projections which extend substantially vertically from the substrate surface, wherein the projections have a height, cross-section and a distance between one another that defines a space between the projections capable of generating capillary flow parallel to the substrate surface.
10. An assay device as claimed in claim 8 , where at least a part of the fluid flow path has a substrate surface and a porous media capable of generating capillary flow parallel to the substrate surface.