An Aptamer-Initiated Catalytic hairpin assembly fluorescent biosensor for simultaneous detection of major seafood allergens in food system

Seafood allergy represents a critical public health challenge, necessitating the implementation of sensitive, precise, and quantitative detection methods for seafood allergens to guarantee accurate food labeling. Parvalbumin (PV) and tropomyosin (TM) are recognized as the primary allergens in fish and shellfish. Herein, we designed a fluorescence sensing system for the simultaneous detection of PV and TM that employs aptamer-initiated catalytic hairpin assembly (CHA). In this strategy, we utilized four hairpin dimers (H1, H2, H3, and H4) as foundational elements to create the sensing scaffolds. The CHA-based fluorescent aptasensor demonstrated an extensive linear range, ranging from 0.001 μg/mL to 100 μg/mL, with detection limits of 0.29 μg/mL for PV and 0.27 μg/mL for TM. This biosensor demonstrates exceptional selectivity and stability, in addition to good accuracy. Importantly, this biosensor has been effectively utilized to quantify PV and TM in four different commercial food products, achieving satisfactory accuracy. With these advantages, our proposed CHA-based aptasensor can offer a universal tool for sensitive and precise detection of food allergens in commercial foods throughout the supply chain.