Dou X, Zhang Z, Li C, Du Y, Tian F. A novel nanoparticle-based fluorescent sandwich immunoassay for specific detection of Salmonella Typhimurium.
Int J Food Microbiol 2024;
413:110593. [PMID:
38308876 DOI:
10.1016/j.ijfoodmicro.2024.110593]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 01/16/2024] [Accepted: 01/19/2024] [Indexed: 02/05/2024]
Abstract
The diseases caused by foodborne pathogens have a serious impact on human health and social stability. Conventional detection methods can involve long assay times and complex pretreatment steps, making them unsuitable for rapid, large-scale analysis of food samples. We constructed a novel nano-fluorescence sandwich immunosorbent immunoassay (nano-FSIA) to rapidly detect Salmonella Typhimurium in food, based on strong covalent binding between streptavidin and biotin. We used antibodies coupled to large particle-size fluorescent microspheres as fluorescent probes for direct quantitative analysis of S. typhimurium in milk. The optimized parameters were determined, and specificity and sensitivity were validated in phosphate-buffered saline (PBS) and milk. The results demonstrated a wide dynamic detection range for S. typhimurium (103-108 colony forming units [CFU]/mL), with the limit of detection in PBS and milk at 234 and 346 CFU/mL, respectively. The results of nano-FSIA were consistent with those of plate counts and enzyme-linked immunosorbent assays, providing an effective and promising single-bacterium counting method for the rapid detection of Salmonella.
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