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 membranes1-3. A molecular theory for predicting SLB formation from different lipid solutions and substrates is instrumental for engineering design, development and applications4-6. 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 effects7,8. 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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