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Updated: Aug 16, 2026
10:15
Atomic Force Microscopy Imaging and Force Spectroscopy of Supported Lipid Bilayers
Published on: July 22, 2015
Budding and domain shape transformations in mixed lipid films and bilayer membranes
J L Harden1, F C Mackintosh, P D Olmsted
1Department of Chemical Engineering, Johns Hopkins University, Baltimore, Maryland 21218-2689, USA. harden@jhu.edu
Summary
Domains with spontaneous curvature in fluid membranes transition from circular shapes to stripes at higher concentrations. Increasing line tension causes a budding transformation from circular domains to spherical buds, revealing a full phase diagram.
Area of Science:
- Physics
- Materials Science
- Biophysics
Background:
- Fluid membranes and films exhibit complex behaviors due to spontaneous curvature.
- Domains within membranes can arise from impurities or phase separation.
- Understanding domain stability and shape is crucial for membrane physics and biology.
Purpose of the Study:
- To investigate the stability and shapes of domains with spontaneous curvature in fluid membranes.
- To determine the phase transitions of these domains under varying impurity concentrations and line tensions.
- To map the complete phase diagram of domain configurations.
Main Methods:
- Utilizing the Monge representation to calculate membrane shapes.
- Employing numerical simulations to analyze domain transformations.
- Calculating phase diagrams and identifying coexistence points.
Main Results:
- An equilibrium phase of protruding circular domains (caplets) is observed at low impurity concentrations.
- A transition from circular domains to stripe phases occurs at higher concentrations.
- Increasing line tension induces a budding transformation from circular domains to spherical buds.
Conclusions:
- The study reveals distinct domain phases and transitions in fluid membranes with spontaneous curvature.
- A comprehensive phase diagram is presented, including two triple points.
- These findings contribute to the understanding of membrane morphology and phase behavior.
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