Modification-Free Oligonucleotide-Utilized Lateral Flow Assay System for On-Site Detection of Foodborne Pathogens.

Area of Science:

• Food safety
• Microbiology
• Biotechnology

Background:

• Foodborne infectious diseases pose significant public health and economic challenges globally.
• Rapid and accurate detection of foodborne pathogens is crucial for effective food safety management.

Purpose of the Study:

• To develop a novel, modification-free lateral flow assay (M-FLASH) for sensitive, on-site detection of foodborne pathogens.
• To enhance the system's suitability for field diagnostics through integrated DNA extraction and amplification strategies.

Main Methods:

• Developed a modification-free lateral flow assay (M-FLASH) utilizing specific oligonucleotide hybridization with loop-mediated isothermal amplification (LAMP) products.
• Integrated thermal lysis for DNA extraction and direct LAMP without purification.
• Employed salt-mediated immobilization of nucleic acids (SAIoNs) for capture probe immobilization and microwave-assisted methods for reporter probe-gold nanoparticle (AuNP) conjugation.

Main Results:

• The M-FLASH system demonstrated high specificity, detecting *Escherichia coli* O157:H7 at levels as low as 10^1 CFU/mL within 2 hours.
• The assay successfully analyzed pathogens in artificially contaminated food samples and showed universal applicability for *Listeria monocytogenes* detection.
• Multiplex detection of *E. coli* O157:H7 and *L. monocytogenes* was achieved, highlighting the system's versatility.

Conclusions:

• The modification-free M-FLASH system offers a sensitive, specific, and cost-effective solution for on-site foodborne pathogen detection.
• The integrated approach simplifies sample processing, making it suitable for resource-limited settings.
• This platform holds significant potential for the detection of various bacterial and viral pathogens, enhancing global food safety surveillance.