Preparation of DOPC and DPPC Supported Planar Lipid Bilayers for Atomic Force Microscopy and Atomic Force Spectroscopy

International Journal of Molecular Sciences

Simon J. Attwood¹  Youngjik Choi² 

[1]Department of Physics and Astronomy, University of Waterloo, Waterloo, ON N2L 3G1, Canada

[2] E-Mail:

[3]Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada

[4] E-Mail:

关键词: DOPC;    DPPC;    AFM;    force spectroscopy;    supported lipid bilayer;    vesicle fusion;    breakthrough forces;    force volume;   

DOI  :  10.3390/ijms14023514

来源: mdpi

【 摘 要 】

Cell membranes are typically very complex, consisting of a multitude of different lipids and proteins. Supported lipid bilayers are widely used as model systems to study biological membranes. Atomic force microscopy and force spectroscopy techniques are nanoscale methods that are successfully used to study supported lipid bilayers. These methods, especially force spectroscopy, require the reliable preparation of supported lipid bilayers with extended coverage. The unreliability and a lack of a complete understanding of the vesicle fusion process though have held back progress in this promising field. We document here robust protocols for the formation of fluid phase DOPC and gel phase DPPC bilayers on mica. Insights into the most crucial experimental parameters and a comparison between DOPC and DPPC preparation are presented. Finally, we demonstrate force spectroscopy measurements on DOPC surfaces and measure rupture forces and bilayer depths that agree well with X-ray diffraction data. We also believe our approach to decomposing the force-distance curves into depth sub-components provides a more reliable method for characterising the depth of fluid phase lipid bilayers, particularly in comparison with typical image analysis approaches.

【 授权许可】

CC BY   
© 2013 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland.