Poly- and monoclonal antibody-based ELISAs for fipronil

An enzyme-linked immunosorbent assay (ELISA) for fipronil was developed by using polyclonal antibodies (pABs) or monoclonal antibodies (mABs), and its suitability of the determination of this analyte in spiked water samples was studied. The pABs-based assay showed I50 = 17.95 ppb, I90 = 203.40 ppb, and I10 = 0.066 ppb, whereas the mABs-based assay showed I50 = 5.99 ppb, I90 = 485.40 ppb, and I10 = 0.074 ppb. The recoveries of fipronil from tap water samples by pABs-based ELISA were 93.00-124.00% in the range of 0-500 ng/mL, and those obtained from the samples by mABs-based ELISA were 94.70-108.00%. Different types of water from pool, river, and sea were spiked at different levels (ranging form 0.1 to 10 microg/L) and were assayed by the indirect ELISA with mABs. The recoveries of fipronil by this ELISA were in the range of 80-120%. The results demonstrate that this assay is suitable for the quantitative detection of fipronil at trace levels in water samples.