Multi-mode probe based on dual colorimetric and photothermal later flow immunoassay for the ultrasensitive determination of benzo[a]pyrene in vegetable oils

Lateral flow immunoassays (LFIA) have been acknowledged as the promising on-site screening method for food survey. Monoclonal antibodies against benzo[a]pyrene (BaP) conjugated with enzyme-mimetic probes, a multi mode LIFA strips were systemically constructed and evaluated. The PBNPs@mAbs based LFIA could conduct triple measurement in 14 min. This assay had good limit of detections (LODs of 0.057, 0.035, and 0.106 μg kg⁻¹), ultra calibration ranges (0.23–500, 0.076–56, 0.69–167 μg kg⁻¹), and the recoveries ranging from 86 % to 105 % with the precision less than 12 %. Compared with the reported methods, the LODs were 175-, 285- and 94- folds enhanced, and dynamic linear ranges were greatly expanded. Finally, this novel PBNPs@mAbs LFIA assay with simplicity, rapidity, and sensitivity was successfully utilized for the determination of BaP in vegetable oils, which could be used as a superior enzyme-mimetic on-site analytic platform in food safety.