Аннотация:A simple and rapid immunoassay technique called microtiter particle agglutination inhibition (MPAI) for monitoring the level of 2,4-dichlorophenoxyacetic acid (2,4-D) in cereals has been developed. MPAI is a non-instrumental assay based on the agglutination between colored polyacrolein particles sensitized with anti-2,4-D monoclonal antibodies (MAb) and novel synthetic agglutinator 2,4-D-polyacrylamide. The agglutination picture could be detected after I to 1.5 h by the naked eye. The detection limit of 2,4-D in water was 0.25 ng/mL for MPAI in 25 mt sample. The cross-reactivity with structurally related herbicides was not more than 10%. A good correlation between MPAI and polarization fluoroimmunoassay was shown when analysing 2,4-D in cereals.