Ultrasensitive visual detection of the food-borne pathogen via MOF encapsulated enzyme

• Published in: Talanta (Oxford) 2023-07, Vol.259, p.124503-124503, Article 124503
• Main Authors: Liang, Jianwei, Huang, Zhiyang, Wang, Kuiyu, Zhang, Liren, Wan, Yuhao, Yang, Tao, Zeng, Hui
• Format: Article
• Language: English
• Subjects: Animals; Colony Count, Microbial; Escherichia coli O157; Food Microbiology; Instrument-free; Milk; Ultrasensitive; Visual detection; ZIF-8
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2023.124503

Various methods have been made to achieve sensitive detection (10 CFU/mL) of Escherichia coli O157:H7 (E. coli) in real samples, however, they are complex, time-consuming, or instrument-dependent. Enzyme-catalyzed reactions are one of the most efficient methods to amplify signals for sensitive detection. ZIF-8 owning stability, porosity, and high specific area are suitable for embedding enzymes which can effectively protect enzyme activity and thus improve detection sensitivity. Herein, a simple visual assay of E. coli with the limits of detection of 1 CFU/mL was developed based on this stable enzyme-catalyzed amplified system. A microbial safety test of milk, orange juice, seawater, cosmetic, and hydrolyzed yeast protein, was successfully performed with the limits of detection of 10 CFU/mL by the naked eye. And this bioassay possessed high selectivity and stability making the developed detection method practically promising. [Display omitted] •A simple and instrument-free visual assay of E. coli owns the LOD of 1 CFU/mL.•Real samples (5 types) were sensitively detected low to 10 CFU/mL by naked eye.•This sensor possesses high stability in room temperature for 3 months.