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arXiv · 1204.1966

Concentration fluctuations and phase transitions in coupled modulated bilayers

Yuichi Hirose·Shigeyuki Komura·David Andelman
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Abstract

We consider the formation of finite-size domains in lipid bilayers consisting of saturated and hybrid lipids. First, we describe a monolayer model that includes a coupling between a compositional scalar field and a two-dimensional vectorial order-parameter. Such a coupling yields an effective two-dimensional microemulsion free-energy for the lipid monolayer, and its characteristic length of compositional modulations can be considered as the origin of finite-size domains in biological membranes. Next, we consider a coupled bilayer composed of two modulated monolayers, and discuss the static and dynamic properties of concentration fluctuations above the transition temperature. We also investigate the micro-phase separation below the transition temperature, and compare the micro-phase separated structures with statics and dynamics of concentration fluctuations above the transition.

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Yuichi Hirose, Shigeyuki Komura, David Andelman. 2012-04-07. Concentration fluctuations and phase transitions in coupled modulated bilayers. https://doi.org/10.1103/physreve.86.021916

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