Rapid and reagentless detection of microbial contamination within meat utilizing a smartphone-based biosensor

Area of Science:

• Food Science
• Biosensor Technology
• Microbiology

Background:

• Microbial spoilage in meat products poses significant food safety risks.
• Current detection methods often require specialized equipment and reagents.
• A rapid, accessible screening tool for microbial contamination is needed.

Purpose of the Study:

• To develop a smartphone-based biosensor for detecting microbial spoilage in ground beef.
• To establish a reagent-free method for preliminary screening of meat products.
• To explore potential applications in diagnosing wound infections.

Main Methods:

• Simulated microbial spoilage using Escherichia coli (E. coli) in ground beef.
• Utilized a smartphone's near-infrared LED, gyro sensor, and camera to analyze light scatter.
• Investigated Mie scatter patterns at varying angles correlated with E. coli concentration.

Main Results:

• The angle of maximum Mie scatter correlated with E. coli concentration (e.g., 15° for 10^8 CFU/mL).
• SEM and fluorescence microscopy showed E. coli binding to meat fat particles.
• Aggregate size and morphology varied with E. coli concentration.

Conclusions:

• A smartphone biosensor can detect microbial contamination in ground beef without reagents.
• The method shows promise as a preliminary screening tool for food safety.
• Further development could extend its use to detecting wound infections.