Production of a monoclonal antibody against thiacloprid, resistant to matrix interference, and its application in quantitatively immunochromatographic assay.

Thiacloprid (THI) is a neonicotinoid insecticide, and its residues pose potential risks to the ecological environment and human health. In this study, computer simulation technology was applied to analyze THI haptens to ensure the similarity in spatial structure, charge properties, and potential distribution. And anti-THI monoclonal antibodies insensitive to matrix effects were prepared using sample extraction solution to simulate the matrix environment, with the half-maximal inhibitory concentration of 0.070 ng/mL in the matrix environment. Furthermore, a colloidal gold immunochromatographic assay (ICA) was established for the detection of THI residues in fruit and vegetable samples, with a quantitative detection range of 0.880-11.091 μg/kg, 1.669-14.056 μg/kg, 31.570-586.121 μg/kg, and 42.291-778.803 μg/kg in grapes, oranges, cucumbers, and tomatoes, respectively. Real sample testing indicated that this method had good consistency with LC-MS/MS. Therefore, the ICA withstood matrix interference, accurately and effectively determined THI residues in fruit and vegetable samples.