Stabilising lamellar stacks of lipid bilayers with soft confinement and steric effects

Author(s)

Bougis, K. ^[1] ; Rubim, R. Leite ^[2] ; Ziane, N. ^[1] ; Peyencet, J. ^[1] ; Bentaleb, A. ^[1] ; Fevrier, A. ^[1] ; Oliveira, C. L. P. ^[2] ; Andreoli de Oliveira, E. ^[2] ; Navailles, L. ^[1] ; Nallet, F. ^[1]

Affiliation

^[1] Univ Bordeaux, Ctr Rech Paul Pascal, CNRS, F-33600 Pessac - France

^[2] Univ Sao Paulo, Inst Fis GFCx, BR-05314970 Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: EUROPEAN PHYSICAL JOURNAL E; v. 38, n. 7 JUL 16 2015.
• Web of Science Citations: 4

Abstract

Structure and interactions stabilising the lamellar stack of mixed lipid bilayers in their fluid state are investigated by means of small-angle X-ray scattering. The (electrically neutral) bilayers are composed of a mixtures of lecithin, a zwitterionic phospholipid, and Simulsol, a non-ionic cosurfactant with an ethoxylated polar head. The soft confinement of the bilayer hydrophilic components is varied by changing hydration and bilayer composition, as well as the length of the cosurfactant polar head. Structural transitions are observed at low hydration, in the stacking order for the longer cosurfactant, and in the mixed bilayers for the shorter one. At higher hydration, the swelling of the lamellar stacks occurs with a significant, but continuous evolution in the mixed bilayer structure. The bilayer structural changes are discussed in analogy with the so-called ``brush-to-mushroom{''} transition induced by lateral confinement, relevant for long linear polymers grafted onto rigid surfaces, taking also into account the role of vertical confinement. (AU)

• FAPESP's process: 11/16149-8 - Interactions between lipid bilayers - the role of the membrane bending rigidity constant
• Grantee: Rafael Leite Rubim
• Support Opportunities: Scholarships in Brazil - Master