Hapten prediction, monoclonal antibody preparation, and development of an immunochromatographic assay for the detection of fenamiphos.

Fenamiphos (FENA) is an organophosphorus insecticide, and its residues in fruits, vegetables, and the environment have raised concerns. Therefore, it is very important to develop a simple, rapid, and accurate method for FENA detection. In this study, a novel FENA hapten was designed and predicted based on computer-aided simulation technology, and high-performance anti-FENA monoclonal antibodies were screened using a matrix effect-enhanced screening method, with a half-maximal inhibitory concentration of 1.269 ng/mL. Furthermore, a colloidal gold immunochromatographic assay (ICA) was established for the detection of FENA, with calculated limits of detection of 1.030 μg/kg, 0.515 μg/kg, 0.250 ng/mL, and 0.405 μg/kg in oranges, cowpeas, river water, and soil. Spiked recovery experiments and real sample validation showed that the detection results from the ICA and LC-MS/MS were consistent, with a CV < 10 %, indicating that the ICA had good accuracy and stability and shows promise as a rapid screening method for FENA in fruits, vegetables, and the environment.