Reliable detection of Listeria monocytogenes by a portable paper-based multi-biocatalyst platform integrating three biomarkers: Gene hly, acetoin, and listeriolysin O protein

Abstract

As biomarkers for pathogenic Listeria monocytogenes, the detection of gene hly, acetoin, and listeriolysin O (LLO) is of great significance for preventing L. monocytogenes infection and diagnosing Listeriosis. Here, a portable paper-based multi-biocatalyst platform was constructed to identify L. monocytogenes by detecting multiple biomarkers at different levels: gene hly (nucleic acid), acetoin (small molecule metabolite), and LLO (protein). The integrating detections of the three biomarkers were successfully performed by two different modified working electrodes on a single paper-based multi-biocatalyst platform. The sensitive and reliable identification of L. monocytogenes was achieved using the portable paper-based multi-biocatalyst platform with wider detection range (from 1.0 × 104 to 1.0 × 109 CFU mL−1) and lower detection limit (104 CFU mL−1). Additionally, the simpler detection procedure and shorter detection time (2 h) endows the portable platform a better detection performance compared with National Food Safety Standard Method (China-GB 4789.30-2016). Moreover, the results detected by the portable platform in spiked samples were consistent with that obtained by the real-time quantitative polymerase chain reaction method, indicating a good application potential. These unique characteristics suggest that the portable platform provides a reliable identification method for L. monocytogenes.