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Hydration Forces Dominate Surface Charge Dependent Lipid Bilayer Interactions under Physiological Conditions.

ABSTRACT: Lipid bilayer interactions are essential to a vast range of biological functions, such as intracellular transport mechanisms. Surface charging mediated by concentration dependent ion adsorption and desorption on lipid headgroups alters electric double layers as well as van der Waals and steric hydration forces of interacting bilayers. Here, we directly measure bilayer interactions during charge modulation in a symmetrically polarized electrochemical three-mirror interferometer surface forces apparatus. We quantify polarization and concentration dependent hydration and electric double layer forces due to cation adsorption/desorption. Our results demonstrate that exponential hydration layer interactions effectively describe surface potential dependent surface forces due to cation adsorption at high salt concentrations. Hence, electric double layers of lipid bilayers are exclusively dominated by inner Helmholtz charge regulation under physiological conditions. These results are important for rationalizing bilayer behavior under physiological conditions, where charge and concentration modulation may act as biological triggers for function and signaling.

SUBMITTER: Wieser V

PROVIDER: S-EPMC8488952 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Hydration Forces Dominate Surface Charge Dependent Lipid Bilayer Interactions under Physiological Conditions.

Wieser Valentina V Mears Laura L E LLE Barker Robert D RD Cheng Hsiu-Wei HW Valtiner Markus M

The journal of physical chemistry letters 20210917 38

Lipid bilayer interactions are essential to a vast range of biological functions, such as intracellular transport mechanisms. Surface charging mediated by concentration dependent ion adsorption and desorption on lipid headgroups alters electric double layers as well as van der Waals and steric hydration forces of interacting bilayers. Here, we directly measure bilayer interactions during charge modulation in a symmetrically polarized electrochemical three-mirror interferometer surface forces app ...[more]

PMID: 34533315

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Dataset Information

Hydration Forces Dominate Surface Charge Dependent Lipid Bilayer Interactions under Physiological Conditions.

Publications

Hydration Forces Dominate Surface Charge Dependent Lipid Bilayer Interactions under Physiological Conditions.

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