Title: the Uses of Lipid Diversity. from Biophysics to Nanotechnology

Title: The Uses of Lipid Diversity. From Biophysics to Nanotechnology

Roman Volinsky

Oxidation of lipids has been shown to impact virtually all cellular processes. The paradigm has been that this involvement is due to interference with the functions of membrane associated proteins. Extensive evidence suggests correlation of lipid peroxidation with degenerative neurological diseases such as Parkinson’s and Alzheimer’s disease, as well as type 2 diabetes, and cancer. In spite of the obvious relevance of the understanding of the molecular basis of the above ailments the exact mechanisms of action of oxidized lipids have remained elusive. Lipids bearing oxidatively truncated and functionalized acyl chains are known to modify membrane bulk physical properties, such as thermal phase behavior, bilayer thickness, hydration and polarity profiles, manifesting in altered structural dynamics of lipid bilayers, causing eg. augmented membrane permeability, fast lipid transbilayer diffusion (flip-flop), loss of lipid asymmetry (scrambling), as well as phase segregation (formation of ‘rafts’). These changes can be further expected to interfere with lipid-protein interactions, causing inflammation, the apoptosis execution and initiating pathological processes.

Recently, we developed a new “bottom-up” approach for construction of thin-film transparent conductive electrodes through self-assembly of hydrophobically-coated gold nanoparticles within surfactant monolayer templates at the air/water interface. The Au nanostructures could be successfully transferred onto solid transparent surfaces; subsequent annealing and gold enhancement yielded a wide-area network of interconnected conductive Au nanowires. The thin-film electrode exhibits high transparency, can be produced in varying length-scales and surface areas, and could constitute a useful platform for photo-voltaic and nanophotonic device applications.

References:

·  Roman Volinsky, Paavo K.J. Kinnunen, “Oxidized phosphatidylcholines in membrane level cellular signaling. From biophysics to physiology and molecular pathology”, FEBS Lett., 2013, 280, 2806-2816.

·  Roman Volinsky, Riku Paananen and Paavo K.J. Kinnunen, “Oxidized phosphatidylcholines promote phase separation of cholesterol-sphingomyelin domains”, Biophys. J., 2012, 103, 247-254.

·  Ahiud Morag, Liron Philosof-Mazor, Roman Volinsky, Elad Mentovich, Shachar Richter, Raz Jelinek, “Self-Assembled Transparent Conductive Electrodes from Au Nanoparticles in Surfactant Monolayer Templates”, Advanced Materials, 2011, 23, 4327-4331.

·  Roman Volinsky, Lukasz Cwiklik , Piotr Jurkiewicz, Martin Hof, Pavel Jungwirth, and Paavo K.J. Kinnunen “Oxidized Phosphatidylcholines Facilitate Phospholipid Flip-Flop in Liposomes”, Biophys. J., 2011, 101, 1376-1384.

·  Roman Volinsky, Raz Jelinek, “Laser-modulated ordering of Au nanoparticles at the air/water interface", Angew. Chemie, Intl. Ed. Eng., 2009, 121, 4610–4612, Designated a Very Important Paper (VIP).

·  Noa Markovich, Roman Volinsky, Raz Jelinek, "Organized patterns of Au nanoparticles in diacetylene monolayer templates", JACS, 2009, 131, 2430–2431.