Rapid detection of duck ingredient in adulterated foods by isothermal recombinase polymerase amplification assays

Abstract Duck is commonly used for premium meat adulteration. A simple, rapid, accurate, and affordable method is urgently needed for duck ingredient identification. Therefore, we developed two recombinase polymerase amplification (RPA) assays based on the duck-specific Cytb gene for rapid detection of duck ingredient in this study, and there were less than 30 min from sample to answer. Two RPA assays were validated to demonstrate good inter- and intra-species specificity. The real-time RPA could detect as low as 10 pg of duck DNA while the RPA combined with lateral flow test strips (LFS RPA) could detect down to 1 pg, and both could detect 0.1% duck meat adulteration. Then the two RPA assays applicability was confirmed using 113 different foods. The effects of background DNA and whole blood on RPA amplification were also analyzed, which did not affect the feasibility of the developed two RPA assays. The developed real-time RPA and LFS RPA would be promising user-friendly on-site detection methods for rapid detecting duck ingredient in different meat products.