Slaved diffusion in phospholipid bilayers.

Liangfang Zhang; Steve Granick

doi:10.1073/pnas.0502723102

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Slaved diffusion in phospholipid bilayers.

Liangfang Zhang·Steve Granick

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Abstract

The translational diffusion of phospholipids in supported fluid bilayers splits into two populations when polyelectrolytes adsorb at incomplete surface coverage. Spatially resolved measurements using fluorescence correlation spectroscopy show that a slow mode, whose magnitude scales inversely with the degree of polymerization of the adsorbate, coexists with a fast mode characteristic of naked lipid diffusion. Inner and outer leaflets of the bilayer are affected nearly equally. Mobility may vary from spot to spot on the membrane surface, despite the lipid composition being the same. This work offers a mechanism to explain how nanosized domains with reduced mobility arise in lipid membranes.

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Biophysics Diffusion Lipid Bilayers Lipids Macromolecular Substances Phosphatidylcholines Phosphatidylethanolamines Phospholipids Photons Polymers Polyvinyls Proteins Spectrometry, Fluorescence Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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Liangfang Zhang, Steve Granick. 2005-06-20. Slaved diffusion in phospholipid bilayers.. https://doi.org/10.1073/pnas.0502723102

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