A dynamic nucleic acid extraction platform based on compressible chitosan cryogel for foodborne pathogen detection

Area of Science:

• Biomaterials Science
• Molecular Biology
• Food Safety

Background:

• Nucleic acid extraction is critical for pathogen detection but conventional methods are complex and require specialized equipment, limiting their use in resource-limited settings.
• Existing methods often involve harsh chemicals and multiple steps, posing challenges for rapid, on-site diagnostics.

Purpose of the Study:

• To develop a simple, efficient, and portable platform for nucleic acid extraction using a chitosan-derived cryogel (CSC).
• To enable rapid purification of nucleic acids from food samples for pathogen detection, suitable for low-resource environments.

Main Methods:

• A chitosan-derived sponge-like cryogel (CSC) was synthesized for dynamic adsorption-elution-driven nucleic acid separation.
• The CSC was integrated into a Pasteur pipette to create a portable extraction device.
• The device was tested for nucleic acid purification from bacterial cultures and milk samples, followed by quantitative polymerase chain reaction (qPCR) and recombinase polymerase amplification (RPA)-CRISPR/Cas12a assays.

Main Results:

• The CSC demonstrated high nucleic acid binding capacity and rapid adsorption kinetics.
• The portable device successfully purified nucleic acids from Vibrio parahaemolyticus and Salmonella in various samples.
• The method achieved sensitive detection limits (down to 10^3 CFU/mL) and outperformed a commercial kit.
• The extraction process avoided chaotropic salts and organic solvents, offering an environmentally friendly alternative.

Conclusions:

• The developed CSC-based platform provides a simplified, efficient, and portable solution for nucleic acid extraction.
• This method is suitable for sensitive foodborne pathogen detection, particularly in resource-limited settings.
• The technology holds potential for point-of-care diagnostics in food safety applications.