Monoclonal antibody-based icELISA for monitoring fenpyroximate in citrus and apple samples

Fenpyroximate is a systemic phenoxy pyrazole acaricide applied worldwide to prevent and control various phytophagous mites and has the highest activity against young mites. To identify its residues in foods, four haptens of fenpyroximate were designed and an indirect competitive enzyme-linked immunosorbent assay (icELISA) based on monoclonal antibodies (2G4C7) was developed. The assay had a working range of 4.77-187.28 ng/mL and a median inhibition concentration (IC 50 ) of 30.92 ng/mL. It showed the average recovery of 73.3%-119.1% in citrus and apple samples. The icELISA and UPLC-MS/MS test results for samples of various citrus cultivars are remarkably consistent. These results and data represent the icELISA is suitable and applicable for detecting fenpyroximate residuals in fruit and vegetable samples.