Isothermal nucleic acid amplification-based biosensors: The next generation analytical toolkit for point-of-care assay of foodborne pathogens

Background: Foodborne diseases caused by various foodborne pathogens have seriously threatened public health and caused huge economic losses to society. Rapid, sensitive, and timely foodborne pathogen screening is imperative to ensure food safety and public health. Isothermal nucleic acid amplification (INAA), as a powerful analytical toolkit, opens a new avenue for rapid, sensitive, and on-site analysis of foodborne pathogens. Especially the INAA-based biosensors combined INAA with emerging detection tools or strategies, could further improve detection sensitivity, specificity, adaptability versatility, and dependability. Scope and approach: This review comprehensively summarized the advances of INAA-based biosensing detection methods for point-of-care assay of foodborne pathogens. Firstly, the classification, principles, and characteristics of INAA techniques were outlined and compared. Then, the latest advances in next-generation INAA methods for on-site assay of foodborne pathogens by coupling INAA techniques with emerging detection tools or strategies were systematically introduced, including cascade INAA, digital INAA, the targeted and programmable nucleases system (i.e. clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR associated proteins (Cas) and Argonaute nuclease)-mediated INAA, and nanomaterials-assisted INAA. Further, the portable detection devices (e.g., lateral flow assay, microfluidic devices, smartphone-based detection devices, and other devices) for INAA-based detection methods in point-of-care assay of pathogenic bacteria were also summarized. Impressively, future opportunities and challenges in this emerging field were discussed. Key findings and conclusions: As a powerful analytical toolkit, INAA techniques have been successfully combined with emerging detection strategies and portable detection devices, opening a new avenue for rapid, sensitive, and on-site analysis of foodborne pathogens.