Magnet regulating valve reconstructed lab-on-a-disc POCT system

Area of Science:

• Microfluidics
• Biotechnology
• Analytical Chemistry

Background:

• Lab-on-a-disc (LOAD) systems offer portable solutions for pathogen diagnosis.
• Flexible and on-demand reagent manipulation is crucial for LOAD point-of-care testing (POCT) systems.
• Existing LOAD systems require improved methods for reagent control.

Purpose of the Study:

• To develop and integrate a magnet regulating valve (MRV) into a LOAD POCT system.
• To enable multifunctional and on-demand reagent manipulation for pathogen detection.
• To validate the system's performance for sensitive and accurate foodborne pathogen analysis.

Main Methods:

• A novel magnet regulating valve (MRV) was designed and integrated into a centrifugal microfluidic chip.
• The MRV utilizes adjustable magnets and centrifugal force for programmable valve control.
• Silica membrane DNA extraction coupled with fluorescent loop-mediated isothermal amplification (LAMP) was employed for pathogen detection.

Main Results:

• The MRV system successfully controlled reagent storage, sequential release, and reaction blocking.
• The LOAD POCT system achieved sensitive detection of Salmonella Enteritidis, E. coli O157:H7, and S. aureus at 10 CFU/mL within 40 minutes.
• Real food sample analysis demonstrated 97.92% consistency with traditional methods, with 103.44% average recovery.

Conclusions:

• The developed MRV-integrated LOAD POCT system provides precise reagent control for pathogen detection.
• This system offers a promising approach for highly sensitive, rapid DNA-based POCT of multiple foodborne pathogens.
• The technology is suitable for resource-limited settings, enhancing food safety diagnostics.