Ultrasensitive and rapid screening of food allergy risk via aptamer-engineered AuMBA@AgNPs core-shell nanoparticle SERS tags-based lateral flow immunoassay

Trace allergens hidden in food products, particularly those arising from cross-contamination during manufacturing, can elicit severe and potentially life-threatening allergic reactions. This underscores critical demand for rapid and ultrasensitive detection technologies to identify trace-level allergens in food matrices, thereby enabling proactive prevention of food allergy risks. In this study, a surface-enhanced Raman scattering-based lateral flow immunoassay (SERS-LFA) based on the Au MBA @AgNPs-Apt SERS tag was developed for rapid and ultrasensitive screening of the allergenic risks in food. With the competitive detection principle, the SERS-LFA achieved detection of target allergenic proteins with a limit of detection (LOD) of 2.2   ng/mL within 8   min. Notably, by integrating additional test line on the nitrocellulose (NC) membrane, the method was adapted for multi-target detection. Under the optimized conditions, the SERS-LFA could simultaneously detect milk allergenic β-lactoglobulin (β-Lg) and fish allergenic parvalbumin (PV) with LODs of 40   ng/mL and 1.1   ng/mL, respectively. The proposed method demonstrated excellent specificity, reproducibility, and comparable performance to commercial ELISA kits in real-sample analysis, establishing a robust on-site methodology for rapid allergy risk screening in complex food matrices.