Colorimetric/fluorescent bacterial sensing by agarose-embedded lipid/polydiacetylene films.

Area of Science:

• Biomaterials Science
• Analytical Chemistry
• Microbiology

Background:

• Accurate and rapid bacterial detection is crucial for public health and safety.
• Existing methods can be time-consuming or require specialized equipment.
• Development of sensitive, versatile, and visually interpretable bacterial sensors is needed.

Purpose of the Study:

• To develop a novel chromatic and fluorescence-based sensor for bacterial detection.
• To create a sensor capable of rapid, sensitive, and versatile identification of bacterial proliferation.
• To engineer a platform with easily recordable visual outputs for bacterial presence.

Main Methods:

• Constructed agarose-embedded Langmuir-Schaeffer phospholipid/polydiacetylene films on glass supports.
• Utilized films that exhibit colorimetric (blue-red) and fluorescence changes upon interaction with bacterial secretions.
• Incorporated growth nutrients within the agarose matrix to amplify signals and a barrier to reduce background noise.

Main Results:

• The sensor demonstrated dramatic color and fluorescence changes in response to bacterial growth.
• Successfully detected both Gram-negative and Gram-positive bacteria.
• Validated sensor performance in screening physiological fluids (blood, urine) and food samples (meat) for contamination.

Conclusions:

• The developed agarose-embedded film constructs provide a robust platform for bacterial detection.
• Visible color transitions and fluorescence emission are reliable indicators of bacterial presence.
• This generic chromatic platform offers a simple and effective solution for rapid bacterial reporting in diverse applications.