Reagent Zone Deposition Pattern

A method of increasing the width of a reagent plume flowing from a reagent zone and into a detection zone in an assay device comprising:

• providing a liquid sample zone;
• providing a reagent zone downstream and in fluid communication with the sample zone comprising a reagent cell having a line of symmetry in the direction of fluid flow;
• providing a reagent material in the reagent cell, wherein the reagent material includes a first reagent material located at the axis of symmetry and is left-right symmetric, and a second and third reagent material having a substantially identical shape and volume and located in mirror locations from the line of symmetry;
• providing a detection zone in fluid communication with the reagent zone;
• providing a wicking zone in fluid communication with the capture zone having a capacity to receive liquid sample flowing from the capture zone, wherein the sample zone, the detection zone and the wicking zone define a fluid flow path;
• adding sample to the sample zone;
• flowing the sample from the sample zone and into the reagent zone and past the first, second and third reagent materials, whereby sample flowing past the second and third reagent materials forms a second and third reagent plumes along the edges of the reagent cell, and sample flowing past the first reagent material forms a first reagent plume along the line of symmetry of the reagent cell, and
• flowing the sample past the first, second and third reagent materials, whereby the first, second and third reagent plume combine to form a combined reagent plume.