Multi-residue Enzyme-linked Immunosorbent Assay For The Determination Of Pyrethroids

In this paper, a direct competitive enzyme-linked immunosorbent assay (cdELISA) method for determination of pyrethroids in water sample had been developed. A common hapten of pyrethroids was synthesized. One monoclonal antibody (McAb) named2G2E7with broad specificity was obtained after fusion of myeloma cells with spleen cells isolated from BALB/c mice. The McAb was identified for the IgGl isotype. The optimized ELISA used coating antibody at a concentration of0.5μg/well, enzyme tracer at a dilution of1:9×105, PBS of4.5%NaCl. The resulting IC50value for deltamethrin was1.8μg/L, with a limit of detection (IC15) of0.24μg/L. The cross-reactivity of McAb with7pyrethroids was tested, all pyrethroids such as deltamethrin (100%), cypermethrin (120%), fluvalinate (90%), fenvalerate (90%), phenothrin (82%), flcythrinate (75%), and fenpropathrin (60%) were with high cross-reactivities. River water sampers (HaiHe River, TianJin, China) were used here to study the spiked recovery. Matrix effects can be avoided when the water samples were first filtered through a nylon membrane filter and then diluted10-fold with PBS. The recoveries of pyrethroids in spiked water samples ranged from74-108%. In order to validate cdELISA, water samples were also analyzed by GC/ECD, and the results obtained by ELISA were close to those of the GC method.The results indicate that the developed ELISA based on the McAb with broad specificity can accurately simultaneously determine seven pyrethroids in water samples. This method will be useful for the development of pyrethroids detection for ELISA kit.