pH microelectrode: modified Thomas recessed-tip configuration

Area of Science:

• Biomedical Engineering
• Cell Biology
• Electrochemistry

Background:

• Accurate measurement of intracellular pH is crucial for understanding cellular function.
• Existing microelectrodes may have limitations in sensitivity or applicability to small cells.
• Mammalian kidney tubules present a challenge for intracellular pH monitoring due to cell size.

Purpose of the Study:

• To develop a novel pH microelectrode suitable for measuring intracellular pH in small mammalian cells.
• To overcome limitations of existing technologies for micro-scale pH measurements.
• To facilitate research in kidney tubule physiology and cellular energetics.

Main Methods:

• Development of a modified Thomas pH microelectrode using a glass-membrane pH electrode.
• Incorporation of a water-tight seal for enhanced stability and performance.
• Characterization of electrode properties including electrical resistance, sensing chamber volume, and response time.
• Manufacturing of both single- and double-barreled configurations.

Main Results:

• The modified Thomas electrode exhibits low electrical resistance (10^11 omega).
• It features a small sensing chamber (10 microns^3) for precise measurements.
• The electrode demonstrates a rapid response time of 10 seconds.
• The design allows for both single- and double-barreled configurations.

Conclusions:

• The modified Thomas pH microelectrode is a viable tool for intracellular pH measurement in small cells.
• Its characteristics make it particularly suitable for applications in mammalian kidney tubules.
• This development advances the capability for studying cellular physiology at the micro-scale.