Rational Hapten Design Enables a Sensitive and Specific Immunochromatographic Assay for On-Site Rapid Detection of Triflusulfuron-Methyl in Food and Environmental Samples

Given concerns over Triflusulfuron-methyl (Tri) residues and their risks to food safety and ecosystems, we developed a rapid detection method. Using computer-aided technology based on electrostatic potential and charge distribution of Tri, we designed a novel hapten (H2) that induced a favorable immune response. This approach maximally simulated the immune recognition features of the target molecule. The precise structural retention combined with optimized physical and chemical properties effectively enhanced the specificity of antibody recognition. It enabled the generation of a high-performance monoclonal antibody (mAb) 4C6 with a half-maximal inhibitory concentration (IC50) of 1.25 ng/mL. The lateral flow immunoassay (LFIA) achieved visual detection limits of 5, 5, 10 and 5 ng/g in cabbage, apple, sugar beet, and lake water samples, with recoveries of 93.7%-102.3% and coefficients of variation below 8%. And the determined results of positive samples were highly consistent with the results of LC-MS/MS. The LFIA method developed in this study has the advantages of simple operation, low cost and good stability, successfully meeting the need for on-site rapid detection of Tri and providing reliable technical support for the supervision of food and ecological safety.