A Novel Bimetallic Nanozyme-Driven Fluorescence–Colorimetric Dual-Mode Platform for the Rapid Detection of Escherichia coli O157:H7 in Meat Products

Abstract

Foodborne diseases pose a severe threat to human health. As a critical meat-borne pathogen, Escherichia coli O157:H7 (E. coli O157:H7) can trigger severe illnesses such as hemorrhagic enteritis, threatening public safety and causing a huge economic impact on the meat industry. However, previous detection methods have struggled to strike an optimal balance among accuracy, reliability, and efficiency, with various traditional techniques exhibiting obvious technical shortcomings. To overcome these limitations, this study developed a novel biosensor for the rapid detection of E. coli O157:H7 based on bimetallic carbon-based nanozymes. This sensor leverages the superior peroxidase-like activity and excellent intrinsic fluorescence of bimetallic carbon dots, providing a solid foundation for constructing a dual-modal platform combining colorimetry and fluorescence. Ultimately, this collaborative approach enables the rapid and accurate detection of the pathogen, substantially enhancing the reliability and stability of the results with a limit of detection (LOD) of 10 cfu/mL. This research presents significant practical application value and offers an innovative design strategy for developing advanced diagnostic sensors for E. coli O157:H7 and other meat-borne pathogens.