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Molecular motions in lipid bilayers studied by the neutron backscattering technique

Maikel C. Rheinstädter·Tilo Seydel·Franz Demmel·Tim Salditt
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Abstract

We report a high energy-resolution neutron backscattering study to investigate slow motions on nanosecond time scales in highly oriented solid supported phospholipid bilayers of the model system DMPC -d54 (deuterated 1,2-dimyristoyl-sn-glycero-3-phoshatidylcholine), hydrated with heavy water. This technique allows to discriminate the onset of mobility at different length scales for the different molecular components, as e.g.\@ the lipid acyl-chains and the hydration water in between the membrane stacks, respectively, and provides a benchmark test regarding the feasibility of neutron backscattering investigations on these sample systems. We discuss freezing of the lipid acyl-chains, as observed by this technique, and observe a second freezing transition which we attribute to the hydration water.

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Maikel C. Rheinstädter, Tilo Seydel, Franz Demmel, Tim Salditt. 2005-04-17. Molecular motions in lipid bilayers studied by the neutron backscattering technique. https://doi.org/10.1103/physreve.71.061908

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