A Dual Sensor for pH and Hydrogen Peroxide Using Polymer-Coated Optical Fibre Tips

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Optical Sensing

Background:

• Accurate monitoring of hydrogen peroxide (H₂O₂) and pH is crucial in biological and chemical analyses.
• Existing methods often require multiple sensors or invasive procedures.
• A need exists for a single, non-invasive sensor for concurrent H₂O₂ and pH detection.

Purpose of the Study:

• To develop and demonstrate the first single optical fibre tip probe for simultaneous detection of H₂O₂ concentration and pH.
• To validate the sensor's performance for biologically relevant H₂O₂ concentrations and pH measurements.
• To explore the potential of this sensor for non-invasive applications in biological environments.

Main Methods:

• Fabrication of an optical fibre tip probe by embedding two fluorophores, carboxyperoxyfluor-1 (CPF1) and seminaphtharhodafluor-2 (SNARF2), in a polymer matrix.
• Utilizing the distinct optical properties of CPF1 and SNARF2 for concurrent sensing.
• Characterization of the probe's response to varying H₂O₂ concentrations and pH levels.

Main Results:

• The developed fibre probe successfully achieved concurrent detection of both H₂O₂ and pH.
• The sensor demonstrated reproducible pH measurements.
• Accurate detection of H₂O₂ was achieved across a biologically relevant concentration range.
• The sensor showed stable performance and reliability.

Conclusions:

• A novel single optical fibre probe enables simultaneous, non-invasive measurement of H₂O₂ and pH.
• This technology holds significant potential for real-time monitoring in biological systems.
• The sensor offers a promising alternative to existing multi-sensor or invasive detection methods.