Shape fluctuations of microemulsions droplets: Role of surfactant film bending elasticity

Lipid membranes are examples of fluid deformable surfaces, which can be viewed as two-dimensional viscous fluids with bending elasticity. With this solid–fluid duality any shape change contributes to tangential flow and vice versa any tangential flow on a curved surface induces shape deformations. This tight coupling between shape and flow makes curvature a natural element of the governing equations. The modelling and numerical tools outlined in Torres-Sánchez et al. (J. Fluid Mech., vol. 872, 2019, pp. 218–271) open a new field of study by enabling the exploration of the role of curvature in this context.

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Membrane Curvature Induced by Sugar and Polymer Solutions

MRS Proceedings ◽

10.1557/proc-489-101 ◽

1997 ◽

Vol 489 ◽

Cited By ~ 8

Author(s):

H.-G. Döbereiner ◽

A. Lehmann ◽

W. Goedel ◽

O. Selchow ◽

R. Lipowsky

Keyword(s):

Polymer Solutions ◽

Lipid Vesicles ◽

Membrane Curvature ◽

Elastic Membrane ◽

Spontaneous Curvature ◽

Membrane Asymmetry ◽

Bending Modulus ◽

Bending Elasticity ◽

Cellular Organelles

AbstractWe monitor the effect of transversal membrane asymmetry on the morphology of giant uni-lamellar vesicles in sugar and polymer solutions. The shapes of fluid lipid vesicles are governed by the bending elasticity of their membrane which is characterized by the bending modulus and the spontaneous curvature of the bilayer. We present a recently developed technique for the measurement of the spontaneous curvature using quantitative phase contrast microscopy. Different mechanisms for elastic membrane asymmetry and the role of the bending energy concept for the morphology of cellular organelles are discussed.

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Bending Elasticity of Surfactant Films: The Role of the Hydrophobic Tails

Physical Review Letters ◽

10.1103/physrevlett.85.337 ◽

2000 ◽

Vol 85 (2) ◽

pp. 337-340 ◽

Cited By ~ 30

Author(s):

Alois Würger

Keyword(s):

Bending Elasticity

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Temperature dependence of the surfactant film bending elasticity in a bicontinuous sugar surfactant based microemulsion: a quasielastic scattering study

Physical Chemistry Chemical Physics ◽

10.1039/c0cp02044c ◽

2011 ◽

Vol 13 (8) ◽

pp. 3092-3099 ◽

Cited By ~ 18

Author(s):

Stefan Wellert ◽

Matthias Karg ◽

Olaf Holderer ◽

André Richardt ◽

Thomas Hellweg

Keyword(s):

Temperature Dependence ◽

Quasielastic Scattering ◽

Bending Elasticity ◽

Surfactant Film ◽

Scattering Study

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Role of the palmitoylation of surfactant-associated protein C in surfactant film formation and stability

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1996.271.4.l572 ◽

1996 ◽

Vol 271 (4) ◽

pp. L572-L580 ◽

Cited By ~ 7

Author(s):

R. Qanbar ◽

S. Cheng ◽

F. Possmayer ◽

S. Schurch

Keyword(s):

Surface Activity ◽

Protein C ◽

Film Formation ◽

Surface Tensions ◽

Surface Layers ◽

Film Stability ◽

Surface Tension Reduction ◽

Surfactant Film ◽

Lipid Adsorption

The effect of palmitoylation of pulmonary surfactant-associated protein C (SP-C) on the surface activity of phospholipid mixtures of dipalmitoylphosphatidylcholine and phosphatidylglycerol was studied. Phospholipids reconstituted with palmitoylated or depalmitoylated bovine SP-C were examined at neutral and acidic pH using a captive bubble surfactometer. At low pH, effective lipid adsorption and near zero surface tensions upon compression were obtained even with protein-free samples. At physiological pH, only SP-C-containing samples achieved such properties. Lipid adsorption was decreased by prior SP-C depalmitoylation. Bubbles with palmitoylated SP-C were more mechanically stable and required less compression to reach low surface tensions. Subphase depletion experiments showed that dynamically cycled surface layers containing palmitoylated SP-C maintained their surface activity after subphase lipid depletion. In contrast, surface activity was rapidly lost where depalmitoylated SP-C or SP-B was included. Our results indicate that although SP-C palmitoylation has little effect on its ability to enhance lipid adsorption and surface tension reduction, it greatly enhances lipid respreading and film stability and is therefore important for surfactant function.

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