Multimode Immunochromatography Assay Based on Portable Instruments for Sensitive and Rapid Detection of Carbendazim in Real Samples

ABSTRACT The extensive application of carbendazim in agricultural practices has resulted in detectable residues across food commodities, necessitating the development of a rapid, sensitive, and field‐deployable analytical platform for multiscenario monitoring. In this work, the multimode immunochromatography assay based on portable instruments has been constructed for sensitive and rapid detection of carbendazim. Under optimized working parameters, the visual detection mode (Mode 1) has achieved a visual detection limit of 1.0 ng/mL for carbendazim. The immunochromatography assay (Mode 2) based on a portable reader has realized the detection of carbendazim in the range from 1.0 to 500.0 ng/mL with an LOD as low as 0.32 ng/mL. The PC platform (Mode 3) developed in PyCharm software based on RGB values on the T line was conducted for carbendazim, achieving a detection range of 1.0–500.0 ng/mL and an LOD as low as 0.033 ng/mL. The accuracy and effectiveness of the developed multimode immunochromatography assay were successfully verified by HPLC and ELISA for the determination of carbendazim in tomato, cucumber, and tea samples. The proposed multimode immunochromatography assay provides a new mutual verification strategy for the rapid, sensitive detection of carbendazim and other pesticides in fruits and vegetables.