la6b01191_si_001.pdf (134.24 kB)
High Resistivity Lipid Bilayers Assembled on Polyelectrolyte Multilayer Cushions: An Impedance Study
journal contribution
posted on 2016-06-06, 00:00 authored by Eleftheria Diamanti, Danijela Gregurec, María
José Rodríguez-Presa, Claudio A. Gervasi, Omar Azzaroni, Sergio E. MoyaSupported
membranes on top of polymer cushions are interesting
models of biomembranes as cell membranes are supported on a polymer
network of proteins and sugars. In this work lipid vesicles formed
by a mixture of 30% 1,2-dioleoyl-sn-glycero-3-phosphocholine
(DOPC) and 70% 1,2-dioleoyl-sn-glycero-3-phospho-l-serine (DOPS) are assembled on top of a polyelectrolyte multilayer
(PEM) cushion of poly(allylamine hydrochloride) (PAH) and poly(styrene
sodium sulfonate) (PSS). The assembly results in the formation of
a bilayer on top of the PEM as proven by means of the quartz crystal
microbalance with dissipation technique (QCM-D) and by cryo-transmission
electron microscopy (cryo-TEM). The electrical properties of the bilayer
are studied by electrochemical impedance spectroscopy (EIS). The bilayer
supported on the PEMs shows a high resistance, on the order of 107 Ω cm2, which is indicative of a continuous,
dense bilayer. Such resistance is comparable with the resistance of
black lipid membranes. This is the first time that such values are
obtained for lipid bilayers supported on PEMs. The assembly of polyelectrolytes
on top of a lipid bilayer decreases the resistance of the bilayer
up to 2 orders of magnitude. The assembly of the polyelectrolytes
on the lipids induces defects or pores in the bilayer which in turn
prompts a decrease in the measured resistance.
History
Usage metrics
Categories
Keywords
10 7 Ω cm 2electrochemical impedance spectroscopyPAHSuch resistancePolyelectrolyte Multilayer Cushionslipid bilayersImpedance Study2 orderspolymer networklipid membranesdissipation techniquepolymer cushionsPSSwork lipid vesiclesPEMquartz crystal microbalanceEIScell membranesHigh Resistivity Lipid Bilayers AssembledDOPClipid bilayer decreasesDOPSassembly results
Licence
Exports
RefWorks
BibTeX
Ref. manager
Endnote
DataCite
NLM
DC