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Atomic Force Microscopy Imaging and Force Spectroscopy of Supported Lipid Bilayers
Published on: July 22, 2015
Phosphatidylserine/Cholesterol Bilayers Supported on a Polycation/Alkylthiol Layer Pair
1Center on Polymer Interfaces and Macromolecular Assemblies (CPIMA), Department of Chemical Engineering and Materials Science, University of California at Davis, Davis, California, 95616
Journal of Colloid and Interface Science
|July 7, 2000
Summary
Supported lipid bilayers of 1-stearoyl-2-oleoyl phosphatidylserine (SOPS) and cholesterol were found to be mobile at room temperature. These bilayers, studied using surface plasmon resonance (SPR), showed lateral diffusion coefficients around 1x10(-9) cm(2)/s.
Area of Science:
- Biophysics
- Materials Science
- Surface Chemistry
Background:
- Supported lipid bilayers are crucial for understanding cell membrane properties.
- Investigating the influence of cholesterol on lipid bilayer dynamics is essential.
- Developing stable model membrane systems on solid supports is a key challenge.
Purpose of the Study:
- To characterize the structure and dynamics of 1-stearoyl-2-oleoyl phosphatidylserine (SOPS)/cholesterol bilayers.
- To evaluate the mobility and lateral diffusion of lipid bilayers supported on a polycation/alkylthiol substrate.
- To investigate the interaction kinetics of gramicidin with these supported lipid bilayers.
Main Methods:
- Fabrication of a gold surface substrate with a poly(diallyldimethylammonium chloride) (PDDA)/11-mercaptoundecanoic acid (MUA) layer pair.
- Deposition of SOPS/cholesterol lipid membranes via vesicle fusion.
- Utilized surface plasmon resonance (SPR) and fluorescence recovery after photobleaching (FRAP) for analysis.
Main Results:
- Stable, single SOPS/cholesterol bilayers were formed when cholesterol content was below 20%.
- FRAP experiments demonstrated bilayer mobility at room temperature with diffusion coefficients of ~1x10(-9) cm(2)/s.
- SPR successfully monitored the kinetics of gramicidin incorporation into the supported bilayers.
Conclusions:
- The PDDA/MUA substrate effectively supports mobile SOPS/cholesterol lipid bilayers.
- Cholesterol content influences bilayer formation and stability.
- The combined SPR and FRAP approach provides a powerful tool for studying peptide-lipid interactions in supported membranes.
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