Rapid detection of mango allergen in processed foods using an immunomagnetic nanoparticle-based electrochemical immunosensor

This work presents an immunomagnetic nanoparticle (IMNP)-based amperometric immunosensor designed for the detection of 40-kDa major mango allergens, known to potentially induce fatal anaphylactic shock in susceptible individuals. By utilizing IMNPs, the assay selectively isolates and concentrates 40-kDa major mango allergens from food samples, followed by their specific capture using monoclonal antibodies immobilized on gold nanoparticles (AuNPs)-modified screen-printed carbon electrodes. Detection is achieved through a peroxidase-conjugated secondary antibody utilizing an HQ/H2O2 system. With optimized conditions, the immunosensor exhibits exceptional specificity, effectively distinguishing mango from nine other fruits and vegetables, and achieving low limits of detection (LOD) for 40-kDa major mango allergens at 1.45 μg/mL in buffer, 2.25 μg/mL in juice, and 1.45 μg/mL in lactic acid beverage. Validation of the assay was performed using 24 commercial food products, which were analyzed sequentially by Western blot to confirm the immunosensor's results. This validation demonstrated the assay's outstanding specificity at 100 % and high sensitivity at 91.7 %. These results emphasize the immunosensor's capability for rapid and sensitive detection of 40-kDa major mango allergens in processed foods, offering a significant improvement in allergen detection technology.