(145f) Pseudo Phase Diagrams of Supported Lipid Bilayers Formation: A Density Functional Theory Study

Pseudo phase diagrams of supported lipid bilayers formation: a density functional theory study

Xian Kong¹, Diannan Lu¹, Jianzhong Wu², Zheng Liu¹

¹ Department of Chemical Engineering, Tsinghua University, Beijing 100084, China

²Department of Chemical and Environmental Engineering and Department of Mathematics, University of California, Riverside, CA 92521, USA

Solid supported lipid bilayers (SLBs) maintain the structural and dynamical properties of natural lipid bilayer membranes promising for a wide variety of applications including biosensors and biomimetic membranes^1-3. A molecular theory for predicting SLB formation from different lipid solutions and substrates is instrumental for engineering design, development and applications^4-6. Whereas the structure of freestanding lipid bilayers has been the subject of longstanding research, relatively few theoretical studies have been devoted to examine how the supporting solid affect the bilayer structure and phase behavior over various conditions. In this work, we investigate the SLB’s formation possibility using a coarse-grained model and the classical density functional theory (DFT) that accounts for the molecular topology, electrostatic correlations and molecular size effects^7,8. The phase diagrams of supported lipid bilayers in different supporting substrates depend on lipid properties including lipid tail length, lipid head size and charge of the polar head, as well as substrate properties such as surface charge density and hydrophobicity.

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