Membrane fluctuations near a plane rigid surface.
We use analytical calculations and Monte Carlo simulations to determine the thermal fluctuation spectrum of a membrane patch of a few tens of nanometer in size, whose corners are located at a fixed distance d above a plane rigid surface. Our analysis shows that the surface influence on the bilayer fluctuations can be effectively described in terms of a uniform confining potential that grows quadratically with the height of the membrane h relative to the surface: V=(1/2)gammah2. The strength gamma of the harmonic confining potential vanishes when the corners of the membrane patch are placed directly on the surface (d=0), and achieves its maximum value when d is of the order of a few nanometers. However, even at maximum strength, the confinement effect is quite small and has a noticeable impact only on the amplitude of the largest bending mode.
Farago
Oded
O
Department of Biomedical Engineering, Ben Gurion University, Be'er Sheva 84105, Israel.
D003198:Computer Simulation; D003599:Cytoskeleton / Q000502:physiology; D005109:Extracellular Matrix / Q000502:physiology; D005227:Fatty Acids / Q000737:chemistry / Q000502:physiology; D005583:Fourier Analysis; D008051:Lipid Bilayers / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry / Q000502:physiology; D008564:Membrane Potentials; D008962:Models, Theoretical; D008968:Molecular Conformation; D009010:Monte Carlo Method
D005227:Fatty Acids; D008051:Lipid Bilayers; D008055:Lipids