Browse by author
Lookup NU author(s): Dr Nico Paracini, Professor Jeremy LakeyORCiD
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND).
Copyright © 2019 American Chemical Society. We present a reliable method for the fabrication of fluid phase, unsaturated lipid bilayers by self-assembly onto charged Self-Assembled Monolayer (SAM) surfaces with tunable membrane to surface aqueous interlayers. Initially, the formation of water interlayers between membranes and charged surfaces was characterized using a comparative series of bilayers deposited onto charged, self-assembled monolayers by sequential layer deposition. Using neutron reflectometry, a bilayer to surface water interlayer of ∼8 Å was found between the zwitterionic phospholipid 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) membrane and an anionic carboxyl terminated grafted SAM with the formation of this layer attributed to bilayer repulsion by hydration water on the SAM surface. Furthermore, we found we could significantly reduce the technical complexity of sample fabrication through self-assembly of planar membranes onto the SAM coated surfaces. Vesicle fusion onto carboxyl-terminated monolayers yielded high coverage (>95%) bilayers of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) which floated on a 7-11 Å solution interlayer between the membrane and the surface. The surface to membrane distance was then tuned via the addition of 200 mM NaCl to the bulk solution immersing a POPC floating membrane, which caused the water interlayer to swell reversibly to ∼33 Å. This study reveals that biomimetic membrane models can be readily self-assembled from solution onto functionalized surfaces without the use of polymer supports or tethers. Once assembled, surface to membrane distance can be tailored to the experimental requirements using physiological concentrations of electrolytes. These planar bilayers only very weakly interact with the substrate and are ideally suited for use as biomimetic models for accurate in vitro biochemical and biophysical studies, as well as for technological applications, such as biosensors.
Author(s): Clifton LA, Paracini N, Hughes AV, Lakey JH, Steinke N-J, Cooper JFK, Gavutis M, Skoda MWA
Publication type: Article
Publication status: Published
Journal: Langmuir
Year: 2019
Volume: 35
Issue: 42
Pages: 13735-13744
Print publication date: 22/10/2019
Online publication date: 25/09/2019
Acceptance date: 25/09/2019
Date deposited: 05/11/2019
ISSN (print): 0743-7463
ISSN (electronic): 1520-5827
Publisher: American Chemical Society
URL: https://doi.org/10.1021/acs.langmuir.9b02350
DOI: 10.1021/acs.langmuir.9b02350
Altmetrics provided by Altmetric
