Search

【Objective】The present paper aimed to prepare a monoclonal antibody against O,O-diethyl organophosphorus pesticides (DPPs) and establish an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA), so as to provide technological support for rapid detection of organophosphorus pesticide residues.【Method】Compound (E)-3-[4- (diethoxyphosphorothioyloxy) phenyl] acrylic acid was used as hapten to make antigen. Immunized mice were screened to prepare monoclonal cell lines that stably secreted antibodies that recognized DPPs. The positive rate and recognition rate of the fusion cell lines were evaluated and the monoclonal cell lines stably secreting antibodies against DPPs were screened. Then, the best concentration combination of antigen and antibody was selected, and the standard curve of ic-ELISA was established. Based on the cross-reactivity rate of the antibody with 6 DPPs, the broad-spectrum of ic-ELISA was evaluated. The cross reaction between the antibody and quinalphos was the strongest, thus the addition and recovery test of quinalphos was carried out on citrus and fresh orange samples.【Result】Artificial antigens were synthesized successfully, including coating antigen DPPs-OVA and immune antigen DPPs-BSA. Sensitive and broad-spectrum cell line 5G8 was obtained by limited dilution method. 0.5 μg/mL coating antigen DPPs-OVA and 1.0 μg/mL antibody 5G82D5 made up the best working concentration combination. Parathion, a pesticide with high antibody recognition rate in this cell line screening, was selected as the inhibition standard, and its ic-ELISA and standard curve were established. The half inhibitory concentration (IC50) was 41.78 ng/mL, and the detection range(IC20-IC80) was 3.21-239.59 ng/mL. The established ic-ELISA showed varying degrees of cross reactions with 5 DPPs (coumaphos, quinalphos, phorate, methyl parathion and fenthion). The cross-reactivity rate of quinalphos was the highest, which was 19.79%. The recoveries of quinalphos in citrus and orange samples by ic-ELISA and GC were compared. The recoveries of ic-ELISA ranged from 75.80% to 116.12%,while the recoveries of GC ranged from 92.5% to 115.00%. The results of the two methods are in good agreement.【Conclusion】The established ic-ELISA has high cross-validation accuracy by GC method and can rapidly detect quetiapine residues in agricultural products. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Southern Agriculture is the property of Journal of Southern Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)