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Updated: May 21, 2026
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Atomic Force Microscopy Imaging and Force Spectroscopy of Supported Lipid Bilayers
Published on: July 22, 2015
Formation and diffusivity characterization of supported lipid bilayers with complex lipid compositions
1Department of Applied Physics, Chalmers University of Technology, Gothenburg, Sweden.
Langmuir : the ACS Journal of Surfaces and Colloids
|June 19, 2012
Summary
A new method uses a moving supported lipid bilayer (SLB) edge to form complex SLBs from lipid vesicles. This technique enables studies on lipid diffusion and domain formation in more native-like lipid bilayers.
Area of Science:
- Biophysics
- Materials Science
- Surface Chemistry
Background:
- Supported lipid bilayers (SLBs) are crucial models for cell membranes.
- Forming SLBs with complex, native-like lipid compositions can be challenging.
- Adsorbed lipid vesicles often fail to form SLBs spontaneously on certain surfaces like SiO(2).
Purpose of the Study:
- To develop a novel method for forming supported lipid bilayers (SLBs) with complex lipid compositions.
- To investigate the influence of cholesterol on lipid diffusion within SLBs.
- To explore the formation of stationary domains in multicomponent SLBs.
Main Methods:
- Hydrodynamically manipulating the edge of a pre-formed SLB to catalyze the formation of new SLBs from adsorbed lipid vesicles.
- Utilizing a lipid reservoir from an initial SLB to form isolated SLBs with defined compositions.
- Investigating the diffusion of lissamine rhodamine B 1,2-dihexadecanoyl-sn-glycero-3-phosphoethanolamine (rhodamine-DHPE) in SLBs with varying cholesterol content.
- Inducing stationary domains in SLBs composed of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE), and cholesterol.
Main Results:
- The hydrodynamically moved SLB edge successfully catalyzed SLB formation from lipid vesicles that do not spontaneously form SLBs.
- Isolated SLBs were formed with compositions closely matching the adsorbed lipid vesicles (≥95%).
- Lipid diffusion of rhodamine-DHPE decreased by a factor of two with increasing cholesterol content (0% to 50%).
- Stationary domains were successfully induced in SLBs with specific DOPC:DOPE:cholesterol ratios.
Conclusions:
- The hydrodynamic SLB edge manipulation technique provides a versatile method for forming SLBs with challenging lipid compositions.
- This approach facilitates biophysical studies on SLBs, particularly those mimicking native membrane compositions.
- The findings contribute to understanding lipid dynamics and domain formation in complex lipid bilayers.
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