ITN SNAL – Marie Curie Initial Training Network

Simulations of Protein Adsorption on Nanostructured Surfaces

Vladimir Baulin — Thu, 21 Mar 2019 08:57:14 +0000

Scientific Reports, 9, 4694 (2019) Berardo M. Manzi, Marco Werner, Elena P. Ivanova, Russell J. Crawford and Vladimir A. Baulin Recent technological advances have allowed the development of a new generation of nanostructured materials, such as those displaying both mechano-bactericidal activity and substrata that favor the growth of mammalian cells. Nanomaterials that come into contact with biological media such as blood first interact with proteins, hence understanding the process of adsorption of proteins onto these surfaces is highly important. The Random Sequential Adsorption (RSA) model for protein adsorption on flat surfaces was modified to account for nanostructured surfaces. Phenomena related

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The Interaction of Giant Unilamellar Vesicles (GUVs) with the Surface Nanostructures on Dragonfly Wings

Vladimir Baulin — Sat, 12 Jan 2019 11:12:52 +0000

Langmuir, January (2019) S. Cheeseman, Vi Khanh Truong, V. Walter, F. Thalmann, C. M. Marques, Eric Hanssen, J. Vongsvivut, M. Tobin, V. A. Baulin, S. Juodkazis, S. MacLaughlin, G. Bryant, R. J. Crawford, E. P. Ivanova The waxy epicuticle of dragonfly wings contains a unique nanostructured pattern that exhibits bactericidal properties. In light of emerging concerns of antibiotic resistance, these mechano-bactericidal surfaces represent a particularly novel solution by which bacterial colonization and the formation of biofilms on biomedical devices can be prevented. Pathogenic bacterial biofilms on medical implant surfaces cause a significant number of human deaths every year. The proposed

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High-Throughput 3D Visualization of Nanoparticles attached to the Surface of Red Blood Cells

Vladimir Baulin — Wed, 26 Dec 2018 14:21:44 +0000

Nanoscale, December (2018) André Dias, Marco Werner, Kevin Ward, Jean-Baptiste Fleury, Vladimir A. Baulin Blood circulation is the main distribution route for systemic delivery and the possibility to manipulate red blood cells by attaching nanoparticles to their surface provides a great opportunity for cargo delivery into tissues. Nanocarriers attached to red blood cells can be delivered to specific organs by orders of magnitude faster than if diluted in the blood. Another ad-vantage is a shielding from recognition of the immune system, thereby increasing the efficiency of delivery. We present a high-throughput microfluidic method that can monitor the shape of drifting

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Tension-Induced Translocation of Ultra-Short Carbon Nanotube through a Phospholipid Bilayer

Vladimir Baulin — Wed, 21 Nov 2018 06:21:48 +0000

ACS Nano, November (2018) Yachong Guo, Marco Werner, Ralf Seemann, Vladimir A Baulin, and Jean-Baptiste Fleury Increasing awareness of bioeffects and toxicity of nanomaterials interacting with cells puts in focus the mechanisms by which nanomaterials can cross lipid membranes. Apart from well-discussed energy-dependent endocytosis for large objects and passive diffusion through membranes by solute molecules, there can exist other translocation mechanisms based on physical principles. We show the importance of membrane tension on the translocation through lipid bilayers of ultra-short carbon nanotubes (USCNTs). By using a combination of a microfluidic setup and single chain mean field theory we observed that

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Kinetic evolution of DOPC lipid bilayers exposed to α-cyclodextrins

Monika Kluzek — Fri, 06 Jul 2018 12:19:09 +0000

Soft Matter, , (2018) Monika Kluzek, Marc Schmutz, Carlos M. Marques and Fabrice Thalmann Cyclodextrins are cyclic oligosaccharides capable of forming inclusion complexes with a variety of molecules, and as such have been recognized as a pharmaceutical and biotechnological asset. Cyclodextrins are known to interact with the components of cell membranes, and this correlates with a significant degree of cytotoxicity. In this work, we report on the mechanism of degradation of a model dioleoyl-phosphatidylcholine (DOPC) bilayer exposed to a solution with increasing con- centrations of α-cyclodextrins. By combining optical fluorescence microscopy and quartz-crystal microbalance experiments, we study the evolution of

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Bridging molecular simulation models and elastic theories for amphiphilic membranes

Adrien Berthault — Tue, 03 Jul 2018 19:53:24 +0000

J. Chem. Phys., 149, 014902 (2018) Adrien Berthault, Marco Werner, Vladimir A. Baulin The Single Chain Mean Field theory is used to link coarse-grained models of amphiphilic molecules with analytical models for membrane elasticity, where phenomenological parameters are deduced from explicit molecular models and force fields. We estimate the elastic constants based on the free energy of the amphiphilic bilayer in planar and cylindrical geometries on the example of four amphiphilic molecules that differ in length and stiffness. We study how these variations affect the equilibrium bilayer structure, the equilibrium free energy, and the elastic constants. Bending rigidities are obtained

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High Aspect Ratio Nanostructures Kill Bacteria via Storage and Release of Mechanical Energy

Vladimir Baulin — Mon, 25 Jun 2018 13:10:56 +0000

ACS Nano, 114(9), 2165–2173 (2018) Denver P. Linklater, Michael De Volder, Vladimir A Baulin, Marco Werner, Sarah Jessl, Mehdi Golozar, Laura Maggini, Sergey Rubanov, Eric Hanssen, Saulius Juodkazis, Elena P. Ivanova The properties of lipid bilayers in sucrose solutions have been intensely scrutinized over recent decades because of the importance of sugars in the field of biopreservation. However, a consensus has not yet been formed on the mechanisms of sugar-lipid interaction. Here, we present a study on the effect of sucrose on 1,2-dipalmitoyl-sn-glycero-3-phosphocholine bilayers that combines calorimetry, spectral fluorimetry, and optical microscopy. Intriguingly, our results show a significant decrease in

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Structure and Chemical Organization in Damselfly Calopteryx haemorrhoidalis Wings: A Spatially Resolved FTIR and XRF Analysis with Synchrotron Radiation

Vladimir Baulin — Mon, 25 Jun 2018 13:03:38 +0000

Scientific Reports, 8, 8413 (2018) Susan Stuhr, Vi Khanh Truong, Jitraporn Vongsvivut, Tobias Senkbeil, Yang Yang, Mohammad Al Kobaisi, Vladimir A. Baulin, Marco Werner, Sergey Rubanov, Mark J. Tobin, Peter Cloetens, Axel Rosenhahn, Robert N. Lamb, Pere Luque, Richard Marchant, Elena P. Ivanova Insects represent the majority of known animal species and exploit a variety of fascinating nanotechnological concepts. We investigated the wings of the damselfly Calopteryx haemorrhoidalis, whose males have dark pigmented wings and females have slightly pigmented wings. We used scanning electron microscopy (SEM) and nanoscale synchrotron X-ray fluorescence (XRF) microscopy analysis for characterizing the nanostructure and the

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Antioxidant modified amphiphilic polymer improves intracellular cryoprotectant delivery and alleviates oxidative stress in HeLa cells

Alex Chen — Mon, 25 Jun 2018 12:52:19 +0000

Adv Mater Sci, DOI: 10.15761/AMS.1000131 (2017) Alexander Chen, Sergio A Mercado, Nigel KH Slater The design and synthesis of a dual-function, cell permeating polymer with an antioxidative property is described and its use for the intracellular delivery of the cryoprotectant trehalose into HeLa cells is demonstrated. The polymer, PVitE-25, was created by grafting the water insoluble hydrophobic antioxidant (±)-α-Tocopherol (vitamin E) onto pendant carboxylate groups of a biocompatible cell permeating polymer, poly (L-lysine iso-phthalamide) (PLP). The modification increased the intracellular delivery efficiency of the polymer and also introduced an antioxidative effect that was able to reduce 85% of reactive oxygen

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DPPC Bilayers in Solutions of High Sucrose Content

Vladimir Baulin — Mon, 25 Jun 2018 12:44:16 +0000

Biophysical J, 114(9), 2165–2173 (2018) Mattia I. Morandi, Mathieu Sommer, Monika Kluzek, Fabrice Thalmann, André P. Schroder, Carlos M. Marques The properties of lipid bilayers in sucrose solutions have been intensely scrutinized over recent decades because of the importance of sugars in the field of biopreservation. However, a consensus has not yet been formed on the mechanisms of sugar-lipid interaction. Here, we present a study on the effect of sucrose on 1,2-dipalmitoyl-sn-glycero-3-phosphocholine bilayers that combines calorimetry, spectral fluorimetry, and optical microscopy. Intriguingly, our results show a significant decrease in the transition enthalpy but only a minor shift in the transition

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