Confined multilamellae prefer cylindrical morphology. A theory of myelin formation.
By evaporating a drop of lipid dispersion we generate the myelin morphology often seen in dissolving surfactant powders. We explain these puzzling nonequilibrium structures using a geometric argument: the bilayer repeat spacing increases and thus the repulsion between bilayers decreases when a multilamellar disk is converted into a myelin without gain or loss of material and with number of bilayers unchanged. Sufficient reduction in bilayer repulsion can compensate for the cost in curvature energy, leading to a net stability of the myelin structure. A numerical estimate predicts the degree of dehydration required to favor myelin structures over flat lamellae.
Huang
J-R
JR
James Franck Institute and Department of Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637, USA. jhuang2@uchicago.edu
Zou
L-N
LN
Witten
T A
TA
D003198:Computer Simulation; D008051:Lipid Bilayers / Q000737:chemistry*; D008081:Liposomes / Q000737:chemistry*; D008560:Membrane Fluidity; D008567:Membranes, Artificial; D008956:Models, Chemical; D008968:Molecular Conformation; D009186:Myelin Sheath / Q000737:chemistry*
D008051:Lipid Bilayers; D008081:Liposomes; D008567:Membranes, Artificial