A Rapid and Sensitive Salmonella Biosensor Based on Viscoelastic Inertial Microfluidics

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Food Safety

Background:

• Salmonella is a primary cause of foodborne illness, necessitating rapid detection methods.
• Current Salmonella detection techniques are often time-consuming, require complex sample preparation, or lack sensitivity.
• Effective screening is crucial for preventing widespread Salmonella outbreaks.

Purpose of the Study:

• To develop a novel microfluidic biosensor for rapid and sensitive Salmonella detection.
• To integrate viscoelastic inertial microfluidics with enzyme catalytic colorimetry for enhanced signal amplification and separation.
• To provide a cost-effective and user-friendly alternative to existing Salmonella detection methods.

Main Methods:

• Utilized magnetic nanoparticles (MNPs) modified with polyclonal antibodies and horseradish peroxidase (HRP) to capture Salmonella.
• Employed viscoelastic inertial microfluidics in a T-shaped channel for separating magnetic HRP-bacteria from unbound MNPs.
• Implemented enzyme catalytic colorimetry for signal amplification and detection of captured Salmonella.

Main Results:

• The developed biosensor achieved sensitive detection of Salmonella down to 30 CFU/mL.
• The entire detection process was completed within 1 hour.
• Demonstrated efficient separation of magnetic HRP-bacteria from unbound MNPs using viscoelastic flow dynamics.

Conclusions:

• The microfluidic biosensor offers a rapid, sensitive, and cost-effective solution for Salmonella detection.
• The integrated approach of magnetic separation and enzyme catalysis simplifies the detection process.
• This technology has significant potential for improving food safety and preventing foodborne illnesses.