| Antiserum was produced by immuning Balb/c mice with the artificial antigen systhesized in the laboratory. Then hybridoma cells were produced by fusion of mice spleen cells with sp2/0 cells, and four hybridoma cell lines were screened from the semi-solid culture medium which contained HAT. The monoclonal antibody in ascites of the four cell lines were characterized and the results showed that all antibodies had very high specificity, which provided a foundation for the detection of Deltamethrin by ELISA and immuno-affinity technology.1. The immune response could be induced effectively by the artificial antigen, and the highest titers of the antiserum was achieved 1:64000,as the cross-reactivity was 0.117μg/mL and 0.160μg/mL,respectively.2. The culture method of fusion cell was optimized, and the survival rate of hybridoma cells was highly improved . By comparison of liquid culture medium, the semi-solid medium was adopted and the clone cycle was shortened with decreased polluting rate of the hybridomas.3. Four strains of stable secreting monoclonal antibodies against deltamethrin hybridoma cell lines were established by combination of indirect non-competitive and indirect competitive ELISA screening, which were named 2B12, 2C1, 2F1 and 3D4, respectively. Three monoclonal antibodies 2B12,2F1,3D4 are all IgG1 type and 2C1 is IgG2b type characterized by ELISA. The molecular weight of three mcAbs were determined by SDS-PAGE electrophoresis, 2B12,2C1,2F1,3D4 heavy chains were all 50KD and light chain are all 25KD. Ascites titers of four cell lines all reached to 1:5.12×105～1:1.024×106. The affinity constants of four monoclonal antibodies 2B12, 2C1, 2F1 and 3D4 were 7.161×108 L/moL, 2.05×108 L/moL, 7.0×108 L/moL, 6.7×108 L/moL, respectively. In the experiment of specificity, the cross reaction of the four antibodies with type I pyrethroids no cross reaction was found with deltamethrin, and the cross-reactivity with type II pyrethroids was enhanced as the structure being close to the deltamethrin, but the hightest CR was no more than 35%.4. A competitive enzyme-linked immunosorbent assay (ELISA) based on monoclonal antibodies (2B12) was developed for the quantitative detection of deltamethrin. The IC50 for deltamethrin was 17.0±3.3μg/L, and the lower detection limit was 1.2±1.3μg/L, The working range was assigned to a concentration 0.501μg/L～499.8μg/L. To reduce the analysis time, the river water samples were pretreated with filter paper to clean-up. River water samples fortified with deltamethrin were analyzed according to this method. 89±2.5%～107.9±6.3% recoveries were observed as the the spike levels ranging from 10 to 1000μg/L. These results suggested that the developed ELISA could be used for the rapid and sensitive determination of deltamethrin in agro-food and environment.
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