Cell-based biosensor for rapid screening of pathogens and toxins

Area of Science:

• Biotechnology
• Food Science
• Microbiology

Background:

• Food safety and defense are critical global concerns.
• Rapid and accurate detection of foodborne pathogens and toxins is essential.
• Existing detection methods may lack specificity or speed.

Purpose of the Study:

• To develop and validate a mammalian cell-based biosensor for food defense and safety.
• To create prototypes capable of analyzing diverse food and beverage samples.
• To assess the biosensor's ability to differentiate between pathogenic and non-pathogenic agents and active vs. inactive toxins.

Main Methods:

• Utilized a B lymphocyte Ped-2E9 cell line encapsulated in a 3D collagen scaffold as the sensing element.
• Developed three biosensor prototypes for different sample types.
• Tested prototypes with various food matrices (ready-to-eat meat, rice, milk) and beverages, spiked with known pathogens and toxins.

Main Results:

• The biosensor detected a wide range of bacterial pathogens (e.g., Listeria monocytogenes, Bacillus) and toxins (e.g., alpha-hemolysin, listeriolysin O).
• Achieved detection limits of 10-40 ng for toxins in 2 hours and 10^3-10^4 CFU/ml for L. monocytogenes in 4-6 hours.
• Successfully identified pathogens and active toxins in real food and beverage samples, even with background microflora present.
• Prototypes II and III demonstrated suitability for particulate food analysis.

Conclusions:

• The developed mammalian cell-based biosensor shows significant promise for the rapid, simultaneous detection of multiple foodborne pathogens and toxins.
• This technology offers a valuable tool for enhancing food defense strategies and ensuring food safety.
• The biosensor's ability to differentiate agent activity and pathogenicity provides accurate risk assessment capabilities.