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Updated: May 30, 2026
08:06
Merging Ion Concentration Polarization between Juxtaposed Ion Exchange Membranes to Block the Propagation of the Polarization Zone
Published on: February 23, 2017
Protons migrate along interfacial water without significant contributions from jumps between ionizable groups on the
Andreas Springer1, Volker Hagen, Dmitry A Cherepanov
1Institut für Biophysik, Johannes Kepler Universität, Linz, Austria.
Summary
Proton diffusion along cell membranes is fast, driven by interfacial water, not membrane-bound sites. This finding impacts understanding of energy transduction and cellular processes.
Area of Science:
- Biophysics
- Cellular Biology
- Physical Chemistry
Background:
- Proton diffusion along membrane surfaces is crucial for cellular energy transduction.
- Current models often assume proton transport occurs via jumps between membrane-bound sites.
Purpose of the Study:
- To investigate the mechanism of proton diffusion along membrane surfaces.
- To determine whether proton transport relies on membrane-bound sites or interfacial water.
Main Methods:
- Utilized UV flashes to release caged protons and fluorescence measurements to track their diffusion.
- Examined proton arrival kinetics at varying distances across different membranes and water isotopes (H2O vs. D2O).
Main Results:
- Observed rapid proton diffusion along membranes, even without ionizable membrane groups.
- Demonstrated a significant decrease in diffusion rate with heavy water (D2O) compared to normal water (H2O).
Conclusions:
- Concluded that fast proton transport along membranes is primarily mediated by interfacial water.
- Ruled out ionizable lipid moieties as the dominant mechanism for this rapid diffusion.
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