Reveal® Q+ is a single step lateral flow immunochromatographic assay based on a competitive immunoassay format. The extract is wicked through a reagent zone, which contains antibodies specific for toxin conjugated to colloidal gold particles. If the toxin is present, it will be captured by the particle-antibody complex. The toxin-antibody-particle complex then is wicked onto a membrane, which contains a zone of toxin conjugated to a protein carrier. This zone captures any uncomplexed toxin antibody, allowing the particles to concentrate and form a visible line. As the level of toxin in a sample increases, free toxin will complex with the antibody-gold particles. This allows less antibody-gold to be captured in the test zone. Therefore, as the concentration of toxin in the sample increases, the test line density decreases. Algorithms programmed into the AccuScan® readers convert these line densities into a quantitative result displayed in ppb or ppm. The membrane also contains a control zone where an immune complex present in the reagent zone is captured by an antibody, forming a visible line. The control line will always form regardless of the presence of toxin, ensuring the strip is functioning properly.