Abstract
By combining molecular dynamics simulations and analytical arguments, we investigate the elastic properties of charged lipid bilayers. We show that electrostatic interactions between the head groups can lead to solidification of the lipid bilayer that would otherwise be in a liquid state if the charges were absent. All elastic parameters of the bilayer such as the bending rigidity κ and the two-dimensional bulk modulus λ and Youngs modulus Y are found to depend on the values of the charges assigned to the lipid head groups. To extract κ and λ, we fit the molecular dynamics data to a standard elastic model for lipid bilayers. Moreover, we analytically obtain the dependence of the Young modulus Y on the relative strengths of electrostatic and van der Waals interactions in the zero temperature limit.
Original language | English (US) |
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Article number | 104905 |
Journal | Journal of Chemical Physics |
Volume | 137 |
Issue number | 10 |
DOIs | |
State | Published - Sep 14 2012 |
Funding
We would like to thank M. Bedzyk, C. Funkhouser, C. Leung, and L. Palmer for useful discussions. Numerical simulations were performed on the Northwestern High Performance Computing System-Quest and on the TARDIS computer cluster, which is financially supported by the Air Force Office of Scientific Research (AFOSR) under Award No. FA9550-10-1-0167. We thank the U.S. Department of Energy-Basic Energy Sciences Award No. DEFG02-08ER46539 for financial support.
ASJC Scopus subject areas
- General Physics and Astronomy
- Physical and Theoretical Chemistry