| abstract |
The present invention provides devices, methods and kits for detecting the presence of an analyte in a liquid sample and indicating to the user the presence or absence of the analyte through the formation of a recognizable symbol during the assay. In one embodiment, the present invention provides test strips having a matrix including a sample application zone, a reagent zone, and a detection zone. Within the detection zone are located positive and negative control areas, and an analyte binding area. The positive control area contains one or more components that exhibit a first color when dry and a second color when wetted. When the assay is conducted, the positive control area is wetted by the assay fluids and turns to a second color, thereby functioning as a positive procedural control. When analyte is present in the sample, it binds at the analyte binding area, which interacts with the positive control area to form a second recognizable symbol at the detection zone. |