Publications de David Roesel | EPFL Graph Search

Membrane Potential Fluctuations and Water Asymmetry on Plasma Cell and Model Lipid Membranes: Origins, Implications and Properties

Arianna Marchioro, Bryan Zhi Li, Sylvie Roke, Orly Bagunu Tarun, Iwona Swiderska, Maksim Eremchev, David Roesel, Seonwoo Lee, Mischa Samuel Flór

Membrane potential fluctuations have previously been detected using second harmonic (SH) water imaging on neuronal cells and model lipid bilayer membranes. We report that such fluctuations are also visible when membrane potential-sensitive fluorophores are ...

ROYAL SOC CHEMISTRY2025

Dynamic Second Harmonic Imaging of Proton Translocation Through Water Needles in Lipid Membranes

Sylvie Roke, David Roesel, Seonwoo Lee

Proton translocation through lipid membranes is a fundamental process in the field of biology. Several theoretical models have been developed and presented over the years to explain the phenomenon, yet the exact mechanism is still not well understood. Here ...

American Chemical Society (ACS)2024

High throughput wide field second harmonic imaging of giant unilamellar vesicles

Sylvie Roke, Pierre-Marc Jean Marie Dansette, Maksim Eremchev, David Roesel

Cell-sized giant unilamellar vesicles (GUVs) are an ideal tool for understanding lipid membrane structure and properties. Label-free spatiotemporal images of their membrane potential and structure would greatly aid the quantitative understanding of membran ...

AIP Publishing2023

Dynamic second-harmonic imaging of divalent cation translocation through giant vesicle membranes

Sylvie Roke, Maksim Eremchev, David Roesel

SPRINGER2023

Passive transport of Ca2+ ions through lipid bilayers imaged by widefield second harmonic microscopy

Sylvie Roke, Maksim Eremchev, David Roesel

In biology, release of Ca2+ ions in the cytosol is essential to trigger or control many cell functions. Calcium signaling acutely depends on lipid membrane permeability to Ca2+. For proper understanding of membrane permeability to Ca2+, both membrane hydra ...

2023

Water as a contrast agent for imaging interfacial structure and ion transport in giant vesicles

David Roesel

Hydrated lipid bilayer membranes and their asymmetry play a fundamental role in living cells by maintaining and regulating concentration gradients between cells, their environment, and their compartments. They achieve this not only through various channels ...

EPFL2022

Ion-Induced Transient Potential Fluctuations Facilitate Pore Formation and Cation Transport through Lipid Membranes

Sylvie Roke, Maksim Eremchev, David Roesel

Unassisted ion transport through lipid membranes plays a crucial role in many cell functions without which life would not be possible, yet the precise mechanism behind the process remains unknown due to its molecular complexity. Here, we demonstrate a dire ...

2022

Dynamic second-harmonic imaging of lipid membrane hydration induced by copper ions

Sylvie Roke, David Roesel, Seonwoo Lee

SPRINGER2021

Imaging Cu2+ binding to charged phospholipid membranes by high-throughput second harmonic wide-field microscopy

Sylvie Roke, David Roesel, Seonwoo Lee

The interaction of divalent copper ions (Cu2+) with cell membranes is crucial for a variety of physiological processes of cells, such as hormone synthesis and cellular energy production. These interactions would not be possible without membrane hydration. ...

AIP Publishing2021