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Simultaneous detection of pathogenic bacteria using agglutination test based on colored silica nanoparticles
Hui Yu, Guangying Zhao, Wenchao Dou1
1Food Safety Key Lab of Zhejiang Province, Department of Food Quality and Safety, Zhejiang Gongshang University, 18, Xuezheng Street, Hangzhou 310035, PR China. wdou@zjsu.edu.cn.
Abstract:
Aimed to explore an agglutination test which can simultaneously detect two pathogenic bacteria, an agglutination test based on colored silica nanoparticles (colored-SiNps) was established in this work. Monodisperse colored-SiNps were used as agglutination test carriers; red-SiNps and blue-SiNps were prepared by reverse microemulsion with C.I. Reactive red 136 and C.I. Reactive Blue 14. Then the red-SiNps were sensitized with antibodies against E. sakazaki and denoted as IgG-red-SiNps; The blue-SiNps were coated with antibodies against S. pullorum and S. Gallinarum and denoted as IgGblue- SiNps. The mixture solution of IgG-red-SiNps and IgG-blue-SiNps could simultaneously agglutinate with E. sakazakii and S. pullorum and S. gallinarum on glass slide. The E. sakazakii and S. pullorum and S. gallinarum could be simultaneously detected by agglutination test with obvious agglutination phenomena. The E. sakazakii and S. pullorum and S. gallinarum could both be detected in a range from 4×10(3) to 4×10(9) CFU/mL. The pullorum and S. gallinarum and E. sakazakii in the infected food sample were detected by mixture solution of IgG-red-SiNps and IgG-blue-SiNps too. This agglutination test was easy and rapid, it might be useful for in situ rapid detection method for simultaneously screening different pathogenic microorganisms of foods and feeds in the field.
Insights
A new agglutination test uses colored silica nanoparticles to simultaneously detect multiple foodborne pathogens like E. sakazakii and S. pullorum. This rapid, in situ method offers a promising tool for food safety screening.
Area of Science:
- Nanotechnology
- Microbiology
- Food Science
Background:
- Simultaneous detection of multiple foodborne pathogens remains a challenge.
- Existing methods can be time-consuming and require specialized equipment.
- Rapid, on-site detection is crucial for effective food safety management.
Purpose of the Study:
- To develop a novel agglutination test for simultaneous detection of pathogenic bacteria.
- To utilize colored silica nanoparticles (colored-SiNPs) as carriers for the agglutination test.
- To establish a rapid and easy method for in situ screening of food and feed contaminants.
Main Methods:
- Monodisperse colored-SiNPs (red and blue) were synthesized using reverse microemulsion.
- Antibodies against E. sakazakii (IgG-red-SiNPs) and S. pullorum/S. gallinarum (IgG-blue-SiNPs) were prepared.
- A mixture of antibody-conjugated SiNPs was used for simultaneous agglutination tests.
Main Results:
- The developed agglutination test successfully detected E. sakazakii, S. pullorum, and S. gallinarum simultaneously.
- Obvious agglutination phenomena were observed, indicating the presence of target bacteria.
- The detection range for these pathogens was established from 4×10^3 to 4×10^9 CFU/mL.
- The method was validated by detecting pathogens in spiked food samples.
Conclusions:
- A novel, rapid agglutination test using colored-SiNPs enables simultaneous detection of multiple foodborne pathogens.
- This method is sensitive, specific, and suitable for in situ applications.
- The test offers a valuable tool for rapid screening of pathogenic microorganisms in food and feed, enhancing food safety.
