A recently developed one step immunological assay system is being proposed to address the need for a rapid method for identifying infectious agents that have military importance. The test system consists of a dipstick and a sealed envelope containing lyophilized precolored reactants. The reactants consist of molecular complexers of antibody molecules which are preamplified with colored avidin/biotin residues. The test is performed by the addition of two drops of the test solution, to solubilize the reactants and permit interaction fo the antibodies with the antigen molecules, if present. Color is deposited on the membrane of the inserted dipstick to form either a plus or minus sign during an initial 15 minute incubation period, to indicate the presence or absence of the antigen. The test system is portable, economical, easy to use and sensitive to less than a nanogram of antigen.
