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Updated: Sep 10, 2025
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In vitro Monitoring of Extracellular pH in Real-Time
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A Method for in Situ Interfacial pH Detection.
Karina N Catalan1, Aaron D Ratschow1, Hans-Jürgen Butt1
1Max Planck Institute for Polymer Research, 55128 Mainz, Germany.
The Journal of Physical Chemistry Letters
|August 21, 2025
Summary
Researchers developed a method to accurately measure pH at the surface of functionalized materials. This technique uses pH-sensitive dyes and microscopy, enabling precise environmental sensing and material characterization.
Area of Science:
- Materials Science
- Surface Chemistry
- Analytical Chemistry
Background:
- Functionalized silica surfaces are crucial in various industries.
- Surface modification with aminosilanes alters interfacial pH, complicating measurements.
- Accurate interfacial pH monitoring is essential for understanding surface behavior.
Purpose of the Study:
- To develop a reliable method for in situ interfacial pH monitoring.
- To investigate the relationship between interfacial and bulk pH.
- To enable advanced material characterization and environmental sensing.
Main Methods:
- Functionalizing glass surfaces with aminosilane-coupled pH-sensitive fluorescent dyes.
- Utilizing confocal microscopy to measure dye fluorescence response to pH changes.
- Developing a theoretical model for surface chemistry and electrostatic interactions.
Main Results:
- A linear relationship was found between interfacial and bulk pH.
- Interfacial pH exhibited a narrower range compared to bulk pH.
- Calibrated fluorescence response of grafted dyes allows precise pH monitoring.
Conclusions:
- The integrated approach enables accurate and reliable in situ interfacial pH monitoring.
- This method has significant potential for environmental sensing applications.
- The findings contribute to advanced material characterization techniques.
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