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arXiv · 1202.3912

Anomalous lateral diffusion in a viscous membrane surrounded by viscoelastic media

S. Komura·S. Ramachandran·K. Seki
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Abstract

We investigate the lateral dynamics in a purely viscous lipid membrane surrounded by viscoelastic media such as polymeric solutions. We first obtain the generalized frequency-dependent mobility tensor and focus on the case when the solvent is sandwiched by hard walls. Due to the viscoelasticity of the solvent, the mean square displacement of a disk embedded in the membrane exhibits an anomalous diffusion. An useful relation which connects the mean square displacement and the solvent modulus is provided. We also calculate the cross-correlation of the particle displacements which can be applied for two-particle tracking experiments.

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S. Komura, S. Ramachandran, K. Seki. 2012-02-17. Anomalous lateral diffusion in a viscous membrane surrounded by viscoelastic media. https://doi.org/10.1209/0295-5075%2F97%2F68007

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