Assay Device Having Multiplexing

An assay device for determining the concentration of multiple analytes or controls, where the device is capable of determining the presence or concentration of at least six analytes or controls includes: a fluid flow path; a liquid sample addition zone; a reagent zone downstream and in fluid communication with the sample addition zone containing one or more reagents; multiple detection zones in fluid communication with the reagent zone. The fluid flow path, which extends through the detection zones, has a length capable of having at least six detection zones linearly spaced at least a sufficient distance apart in order to discriminate each signal peak from its adjacent signal peak. The device further includes a wicking zone in fluid communication with the detection zones having a capacity to receive liquid sample flowing from the detection zone. The fluid flow path extends from the sample zone to the wicking zone, and at least a part of the fluid flow path has a substrate and projections which extend substantially vertically from the substrate. 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.