A simple optode based method for imaging O2 distribution and dynamics in tap water biofilms.

Area of Science:

• Analytical Chemistry
• Biotechnology
• Environmental Science

Background:

• Accurate spatial oxygen (O2) measurements are crucial for understanding biofilm dynamics.
• Existing methods like luminescence lifetime imaging are often complex and expensive.
• Transparent planar O2 optodes offer a potential platform for in-situ O2 sensing.

Purpose of the Study:

• To present a novel ratiometric luminescence intensity imaging approach for spatial O2 measurements.
• To enable O2 quantification in biofilm reactors using transparent planar O2 optodes.
• To compare the performance of the new method with luminescence lifetime imaging.

Main Methods:

• Utilized O2-sensitive luminescent dyes immobilized in thin polymeric layers on transparent carriers.
• Employed sequential imaging of O2-dependent luminescence intensity, normalized with anoxic condition images.
• Applied conventional digital cameras for image acquisition.

Main Results:

• Generated 2-dimensional O2 distribution images at the base of a tap water biofilm.
• Achieved high signal-to-noise ratio and spatial resolution comparable to or exceeding lifetime imaging.
• Demonstrated the method's efficacy using standard digital cameras.

Conclusions:

• The ratiometric luminescence intensity imaging method provides a simple, cost-effective alternative for spatial O2 measurements in biofilms.
• This technique is suitable for biofilm growth incubators and systems with fluctuating O2 concentrations.
• The approach offers high-resolution O2 mapping without the need for expensive, complex instrumentation.