Biomimetic Phospholipid Membrane Organization on Graphene and Graphene Oxide Surfaces: A Molecular Dynamics Simulation Study.
Supported phospholipid membrane patches stabilized on graphene surfaces have shown potential in sensor device functionalization, including biosensors and biocatalysis. Lipid dip-pen nanolithography (L-DPN) is a method useful in generating supported membrane structures that maintain lipid functionality, such as exhibiting specific interactions with protein molecules. Here, we have integrated L-DPN, atomic force microscopy, and coarse-grained molecular dynamics simulation methods to characterize the molecular properties of supported lipid membranes (SLMs) on graphene and graphene oxide supports. We observed substantial differences in the topologies of the stabilized lipid structures depending on the nature of the surface (polar graphene oxide vs nonpolar graphene). Furthermore, the addition of water to SLM systems resulted in large-scale reorganization of the lipid structures, with measurable effects on lipid lateral mobility within the supported membranes. We also observed reduced lipid ordering within the supported structures relative to free-standing lipid bilayers, attributed to the strong hydrophobic interactions between the lipids and support. Together, our results provide insight into the molecular effects of graphene and graphene oxide surfaces on lipid bilayer membranes. This will be important in the design of these surfaces for applications such as biosensor devices.
Department of Biochemistry, University of Oxford , South Parks Road, Oxford OX1 3QU, United Kingdom.
Nathalie
N
Willems
Institute of Nanotechnology (INT) and Karlsruhe Nano Micro Facility (KNMF), Karlsruhe Institute of Technology (KIT) , 76344 Eggenstein-Leopoldshafen, Germany.
Ainhoa
A
Urtizberea
School of Materials and National Graphene Institute, University of Manchester , Manchester M13 9PL, United Kingdom.
Andrea F
AF
Verre
School of Materials and National Graphene Institute, University of Manchester , Manchester M13 9PL, United Kingdom.
Maria
M
Iliut
CERMAV, CNRS and Université Grenoble Alpes , BP 53, Grenoble 38041 Cedex 9, France.
Mickael
M
Lelimousin
Institute of Nanotechnology (INT) and Karlsruhe Nano Micro Facility (KNMF), Karlsruhe Institute of Technology (KIT) , 76344 Eggenstein-Leopoldshafen, Germany.
Michael
0000-0002-2647-5317
M
Hirtz
School of Materials and National Graphene Institute, University of Manchester , Manchester M13 9PL, United Kingdom.
Aravind
0000-0001-8289-2337
A
Vijayaraghavan
Department of Biochemistry, University of Oxford , South Parks Road, Oxford OX1 3QU, United Kingdom.
Mark S P
0000-0001-6360-7959
MS
Sansom
dip-pen nanolithography; molecular dynamics; phospholipid bilayer; polymer pen lithography; supported lipid membranes