title: Preparation of DOPC and DPPC Supported Planar Lipid Bilayers for Atomic Force Microscopy and Atomic Force Spectroscopy.
abstract: 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.
authors: Department of Physics and Astronomy, University of Waterloo, Waterloo, ON N2L 3G1, Canada. zleonenk@uwaterloo.ca.
authors: Simon J
authors: SJ
authors: Attwood
authors: Youngjik
authors: Y
authors: Choi
authors: Zoya
authors: Z
authors: Leonenko
references: Biophys J. 1999 Feb;76(2):1072-9
references: 9916039
references: Langmuir. 2006 Apr 11;22(8):3497-505
references: 16584220
references: Chem Phys Lipids. 2011 Jan;164(1):9-15
references: 20932964
references: J Am Chem Soc. 2010 Sep 22;132(37):12874-86
references: 20799688
references: Methods Cell Biol. 2002;68:51-65
references: 12053740
references: Biophys J. 2004 Jun;86(6):3783-93
references: 15189874
references: Faraday Discuss. 1998;(111):79-94; discussion 137-57
references: 10822601
references: Nat Protoc. 2008;3(10):1654-9
references: 18833202
references: Biochim Biophys Acta. 2007 Jan;1768(1):146-54
references: 17052685
references: ACS Chem Neurosci. 2011 Oct 19;2(10):588-599
references: 22125665
references: Biophys J. 2002 Nov;83(5):2625-33
references: 12414696
references: Chem Phys Lipids. 2012 Dec;165(8):845-60
references: 23194897
references: Proc Natl Acad Sci U S A. 2005 Jul 26;102(30):10427-32
references: 16020533
references: Phys Rev E Stat Nonlin Soft Matter Phys. 2002 Sep;66(3 Pt 1):031602
references: 12366125
references: Biophys J. 2007 Jun 15;92(12):4369-78
references: 17400691
references: Phys Rev E Stat Nonlin Soft Matter Phys. 2002 Nov;66(5 Pt 1):051905
references: 12513521
references: Biochim Biophys Acta. 1997 Mar 13;1324(2):309-19
references: 9092717
references: Biophys J. 2010 Jul 21;99(2):507-16
references: 20643069
references: Biochim Biophys Acta. 2011 Jan;1808(1):405-14
references: 20955684
references: Biophys J. 2012 Jan 4;102(1):L01-3
references: 22225813
references: Biochim Biophys Acta. 2004 Aug 30;1664(2):198-205
references: 15328052
references: Nature. 2009 May 21;459(7245):379-85
references: 19458714
references: Biophys J. 1998 Aug;75(2):917-25
references: 9675192
references: J Phys Chem B. 2010 Mar 18;114(10):3543-9
references: 20175552
references: Biochim Biophys Acta. 2000 Dec 20;1509(1-2):131-47
references: 11118525
references: Biophys J. 2007 Jul 1;93(1):103-12
references: 17416629
references: Biophys J. 1999 Sep;77(3):1683-93
references: 10465778
references: Biochim Biophys Acta. 2006 Apr;1758(4):487-92
references: 16626631
references: Pharm Res. 1998 Oct;15(10):1507-19
references: 9794491
references: Colloids Surf B Biointerfaces. 2010 Oct 15;80(2):232-9
references: 20634046
references: Biochim Biophys Acta. 2009 Jan;1788(1):254-66
references: 18822269
references: Biophys J. 1995 Jan;68(1):171-8
references: 7711239
references: Biophys J. 2000 Dec;79(6):3153-63
references: 11106620
references: Biophys J. 2010 Aug 4;99(3):834-44
references: 20682261
references: Biochemistry. 2000 May 16;39(19):5852-8
references: 10801336
references: Biophys J. 2004 Feb;86(2):870-9
references: 14747322
references: Chemphyschem. 2006 Nov 13;7(11):2409-18
references: 17051578
references: Biochemistry. 2006 Aug 1;45(30):9336-41
references: 16866380
references: Chem Phys Lipids. 2012 Feb;165(2):142-50
references: 22182491
references: Biochim Biophys Acta. 1994 Apr 20;1191(1):225-30
references: 8155680
references: Biophys J. 2005 Sep;89(3):1812-26
references: 15980180
references: Biophys J. 2004 Oct;87(4):2446-55
references: 15454442
references: Biochemistry. 1993 Feb 2;32(4):1127-40
references: 8424941