Monoclonal antibody-based enzyme-linked immunosorbent assays for the organophosphorus insecticide O-ethyl O-4-nitrophenyl phenylphosphonothioate (EPN).
This study aimed at developing competitive direct and indirect enzyme-linked immunosorbent assays (ELISAs) for the organophosphorus insecticide O-ethyl O-4-nitrophenyl phenylphosphonothioate (EPN) using a monoclonal antibody (mAb). Of the five EPN derivatives (haptens) prepared for use as an immunogen or as a competitor, two of them were used as the immunogen for the production of the mAbs. By using the antibody with the highest specificity and a coating antigen (hapten-OVA conjugate), a competitive indirect ELISA was developed, which showed an IC(50) of 2.9 ng/mL with a detection limit of 0.3 ng/mL. A competitive direct ELISA using a different antibody and an enzyme tracer was also developed, which showed an IC(50) of 0.6 ng/mL with a detection limit of 0.09 ng/mL. The mAbs in both assays showed negligible cross-reactivity with other organophosphorus pesticides. The recoveries of EPN from spiked samples determined by the developed ELISA ranged from 59 to 143%. Dilution of the samples improved the recovery. The assay performance of the present ELISAs based on the mAb was compared with that of the EPN ELISAs based on polyclonal antibodies (pAbs) that had been developed previously and was found to be better in dynamic response.
Shim
Jee Youn
JY
Department of Food Science and Nutrition, Kyungpook National University, Daegu, Korea.
Kim
Young Ah
YA
Lee
Yong Tae
YT
Hammock
Bruce D
BD
Lee
Hye-Sung
HS
D000911:Antibodies, Monoclonal / Q000276:immunology*; D000918:Antibody Specificity; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D007306:Insecticides / Q000032:analysis* / Q000276:immunology; D004849:Phenylphosphonothioic Acid, 2-Ethyl 2-(4-Nitrophenyl) Ester / Q000032:analysis* / Q000276:immunology
D000911:Antibodies, Monoclonal; D007306:Insecticides; D004849:Phenylphosphonothioic Acid, 2-Ethyl 2-(4-Nitrophenyl) Ester