MONOCLONAL AND POLYCLONAL ANTIBODIES TO THE ORGANOPHOSPHATE FENITROTHION .2. ANTIBODY SPECIFICITY AND ASSAY PERFORMANCE

The performance and specificities of antibody-based assays for fenitrothion were studied. Fenitrothion could be detected in grain in assays with either polyclonal or monoclonal antibodies using either immobilized antibody or immobilized hapten-protein conjugates. Most assay formats and antibodies distinguished fenitrothion from structurally similar organophosphates, and variable extents of cross-reaction with metabolites were observed. The concentration of fenitrothion in wheat grain samples was measured in three assay formats with two antibodies, and in each case good correlations were obtained with the results obtained by gas-liquid chromatography. For routine use, a format detecting 3 ng and suitable for analysis over the range 100 ppb-20 ppm in grain was preferred.