Preparation of Anti-idiotype Antibodies of O,O-Dimethyl Organophosphorus Pesticides by Phage Display Technology

Anti-idiotype antibodies (AId or Ab2) can be used to develop a noncompetitive immunoassay for hapten molecules. In this work, generic hapten, S-carboxyethyl O,O-dimethyl phosphorodithioate (CMP), was immobilized on sepharose and then used for purification the class-specific antibodies of organophosphorus pesticides. Affinity-purified positive and negative primary antibodies were used for biopanning of AIds from phage display antibody library. After three rounds of panning, 3 α-AId and 9 β-AId positive clones were obtained. Clones D11 and B9, identified as β-AId and α-AId respectively, were selected to develop a noncompetitive immunoassay system. The IC50 value and detection limit of this method for malathion were calculated to be (113.7 ± 34.18) (g L−1 and 10.54 (g L−1, respectively.