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arXiv · 1103.6106

Thermodynamic Approach to Phase Coexistence in Ternary Phospholipi-Cholesterol Mixtures

Jean Wolff·Carlos M. Marques·Fabrice Thalmann
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Abstract

We introduce a simple and predictive model for determining the phase stability of ternary phospholipid-cholesterol mixtures. Assuming that competition between the liquid and gel order of the phospholipids is the main driving force behind lipid segregation, we derive a Gibbs free-energy of mixing, based on the thermodynamic properties of the lipids main transition. A numerical approach was devised that enable the fast and efficient determination of the ternary diagrams associated with our Gibbs free-energy. The computed phase coexistence diagram of DOPC/DPPC/cholesterol reproduces well known features for this system at 10\circ C, as well as its evolution with temperature.

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Jean Wolff, Carlos M. Marques, Fabrice Thalmann. 2011-03-31. Thermodynamic Approach to Phase Coexistence in Ternary Phospholipi-Cholesterol Mixtures. https://doi.org/10.1103/physrevlett.106.128104

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