An In Situ Dual-Mode Bacterial Detection Technique Allowing Both Direct Visual Colorimetric Screening and ATP...

Area of Science:

• Microbiology
• Materials Science
• Analytical Chemistry

Background:

• Foodborne pathogenic bacteria pose significant risks to public health and food safety due to their rapid reproduction.
• Accurate and rapid detection methods for these pathogens are essential for effective control and prevention.

Purpose of the Study:

• To develop a dual-mode in situ detection platform for rapid and accurate bacterial analysis.
• To enable on-site detection without large-scale instrumentation.

Main Methods:

• A phage-immobilized hydrogel stir bar captures target bacteria, causing a pH-induced color change (colorimetric detection).
• Embedded ZnO/ZIF generates reactive oxygen species (ROS) under light, killing bacteria and releasing ATP.
• ATP triggers a bioluminescence reaction quantified by a hand-held sensor, providing a second detection mode.

Main Results:

• The dual-mode platform achieved rapid on-site detection of live bacteria within 35 minutes.
• Detection range: 10³ to 10⁹ CFU·mL⁻¹, with a colorimetric LOD of 10³ CFU·mL⁻¹.
• Bioluminescence mode achieved a limit of quantification (LOQ) of 30 CFU·mL⁻¹, with mutual verification enhancing accuracy and sensitivity.

Conclusions:

• The developed platform offers a sensitive, accurate, and rapid dual-mode detection method for foodborne pathogens.
• Its portable nature facilitates on-site screening and analysis, improving food safety measures.