Development of a rechargeable optical hydrogen peroxide sensor - sensor design and biological application

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Biophysics

Background:

• Hydrogen peroxide (H2O2) is a key reactive oxygen species (ROS) with dual roles in cellular signaling and toxicity.
• Accurate quantification of H2O2 in biological systems is technically challenging.
• Existing methods often lack the necessary spatial or temporal resolution for dynamic biological processes.

Purpose of the Study:

• To develop a quasi-reversible fiber-optic sensor for measuring H2O2 concentrations.
• To achieve high spatial and temporal resolution in H2O2 quantification.
• To demonstrate the sensor's applicability in complex environmental and biomedical samples.

Main Methods:

• Utilized a Prussian blue/white redox cycle for H2O2 detection.
• Implemented a sensor recharging and readout strategy.
• Employed a fiber-optic probe for measurements.

Main Results:

• Successfully measured H2O2 concentrations in the range of 1-100 μM.
• Achieved high spatial resolution of approximately 500 μm and temporal resolution of approximately 30 s.
• Demonstrated H2O2 profiling in photosynthetic biofilms (up to 15 μM) and quantified extracellular H2O2 during neutrophil stimulation.

Conclusions:

• The developed fiber-optic sensor provides a robust method for quantifying H2O2 in diverse biological and environmental samples.
• The sensor's high resolution enables the study of dynamic H2O2 changes in biological systems.
• This technology has broad applicability in environmental monitoring and biomedical research.