title: Mixtures of supported and hybrid lipid membranes on heterogeneously modified silica nanoparticles.
abstract: Simple supported lipid bilayers do not accurately reflect the complex heterogeneity of cellular membranes; however, surface modification makes it possible to tune membrane properties to better mimic biological systems. Here, 3-[2-(2-aminoethylamino)ethylamino]propyl-trimethoxysilane (DETAS), a silica modifier, facilitated formation of supported lipid bilayers on silica nanoparticles. Evidence for a stable supported bilayer came from the successful entrapment of a soluble fluorophore within an interstitial water layer. A fluorescence-quenching assay that utilized a pore-forming peptide was used to demonstrate the existence of two separate lipid leaflets. In this assay, fluorescence was quenched by dithionite in roughly equal proportions prior to and after addition of melittin. When a hydrophobic modifier, octadecyltriethoxysilane, was codeposited on the nanoparticles with DETAS, there was a decrease in the amount of supported bilayer on the nanoparticles and an increase in the quantity of hybrid membrane. This allowed for a controlled mixture of two distinct types of membranes on a single substrate, one separated by a water cushion and the other anchored directly on the surface, thereby providing a new mimic of cellular membranes.
authors: Department of Chemistry, University of Colorado Denver, Campus Box 194, P.O. Box 173364, Denver, Colorado 80217-3364, USA.
authors: Aundrea R
authors: AR
authors: Piper-Feldkamp
authors: Maria
authors: M
authors: Wegner
authors: Peter
authors: P
authors: Brzezinski
authors: Scott M
authors: SM
authors: Reed
mesh_terms: D005029:Ethylenediamines / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D008051:Lipid Bilayers / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D017646:Organosilicon Compounds / Q000737:chemistry; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D012822:Silicon Dioxide / Q000737:chemistry*; D013818:Thermogravimetry
chemical_list: D005029:Ethylenediamines; D008051:Lipid Bilayers; D017646:Organosilicon Compounds; D010455:Peptides; C110457:3-(2-(2-aminoethyl)ethylamino)propyltrimethoxysilane; D012822:Silicon Dioxide
references: Langmuir. 2007 Jan 30;23(3):1354-8
references: 17241058
references: Nat Struct Mol Biol. 2006 Apr;13(4):323-30
references: 16565726
references: Langmuir. 2012 May 29;28(21):8174-82
references: 22568448
references: J Phys Chem B. 2011 Nov 17;115(45):13181-90
references: 21932795
references: Biophys J. 1991 Feb;59(2):289-94
references: 2009353
references: J Cell Biol. 2002 Jun 10;157(6):1071-81
references: 12058021
references: Proc Natl Acad Sci U S A. 2003 Jul 8;100(14):8053-8
references: 12832616
references: Biophys J. 1997 Apr;72(4):1659-67
references: 9083669
references: Biophys J. 1994 Sep;67(3):1229-37
references: 7811937
references: Langmuir. 2011 Jun 7;27(11):7008-15
references: 21520932
references: Langmuir. 2004 Dec 7;20(25):11092-9
references: 15568862
references: Langmuir. 2012 Mar 27;28(12):5404-16
references: 22352432
references: Nanoscale. 2009 Oct;1(1):114-7
references: 20644868
references: J Am Chem Soc. 2009 Jun 10;131(22):7567-9
references: 19445508
references: Biophys J. 1995 May;68(5):1828-35
references: 7612824
references: Langmuir. 2008 Apr 15;24(8):4125-31
references: 18302435
references: Nature. 2001 Sep 13;413(6852):226-30
references: 11557992
references: Nat Rev Mol Cell Biol. 2006 Jun;7(6):456-62
references: 16625153
references: Biophys J. 1998 Sep;75(3):1397-1402
references: 9726940
references: Surf Sci Rep. 2006 Nov 15;61(10):429-444
references: 32287559
references: Langmuir. 2012 Jan 31;28(4):2217-24
references: 22148887
references: Biointerphases. 2008 Jun;3(2):FA22
references: 20408665
references: Nanotechnology. 2008 Mar 19;19(11):115607
references: 21730558
references: ACS Nano. 2010 Aug 24;4(8):4371-9
references: 20731423
references: Nat Rev Mol Cell Biol. 2006 Jan;7(1):9-19
references: 16365634
references: Bioconjug Chem. 2008 Dec;19(12):2471-9
references: 19035793
references: Langmuir. 2011 Dec 6;27(23):14317-28
references: 21962085
references: Langmuir. 2006 Aug 1;22(16):7078-83
references: 16863263
references: Langmuir. 2010 Jul 20;26(14):12081-8
references: 20527833
references: J Am Chem Soc. 2005 May 11;127(18):6752-65
references: 15869298
references: Biophys J. 1990 Aug;58(2):357-62
references: 2207243
references: Curr Opin Chem Biol. 2000 Dec;4(6):704-9
references: 11102877
references: Mol Cell Biol. 2006 Jan;26(1):313-23
references: 16354701
references: Langmuir. 2009 Apr 9;25(6):3682-91
references: 19231878
references: Biophys J. 1997 Apr;72(4):1762-6
references: 9083680
references: Nano Lett. 2005 Feb;5(2):281-5
references: 15794611
references: Chem Commun (Camb). 2008 Jul 14;(26):3013-5
references: 18688332