Posts by Daniela Ciumac published at ITN SNAL - Marie Curie Initial Training Network

Influence of Acyl Chain Saturation on the Membrane-Binding Activity of a Short Antimicrobial Peptide

Daniela Ciumac — Mon, 01 Jan 2018 15:19:25 +0000

ACS Omega, 2(11) 7482–7492 (2017) Daniela Ciumac, Richard A. Campbell, Luke A. Clifton, Hai Xu∥ , Giovanna Fragneto, and Jian R. Lu Different bacterial types and their living environments can lead to different saturations in the chains of their membrane lipids. Such structural differences may influence the efficacy of antibiotics that target bacterial membranes. In this work, the effects of acyl chain saturation on the binding of an antimicrobial peptide G4 have been examined as a function of the packing density of lipid monolayers by combining external reflection Fourier transform infrared (ER-FTIR) spectroscopy and neutron reflection (NR) measurements. Langmuir monolayers

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Implications of lipid monolayer charge characteristics on their selective interactions with a short antimicrobial peptide

Daniela Ciumac — Tue, 30 May 2017 17:37:41 +0000

Colloids and Surfaces B, 150, 308–316 (2017). Daniela Ciumac, Richard A. Campbell, Hai Xu, Luke A. Clifton, Arwel V. Hughes, John R.P. Webster, Jian R. Lu Many antimicrobial peptides (AMPs) target bacterial membranes and they kill bacteria by causing structural disruptions. One of the fundamental issues however lies in the selective responses of AMPs to different cell membranes as a lack of selectivity can elicit toxic side effects to mammalian host cells. A key difference between the outer surfaces of bacterial and mammalian cells is the charge characteristics. We report a careful study of the binding of one of the

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Manchester: SNAL open day

Daniela Ciumac — Sun, 29 Mar 2015 22:00:41 +0000

8 April 2015. SNAL open day in Manchester University, UK Timetable: Venue: Meeting will be held in : School of Physics and Astronomy, University of Manchester, UK Schuster building, Oxford Rd, Manchester M13 9PL United Kingdom

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Neutron reflection (NR) and Small angle neutron scattering (SANS)

Daniela Ciumac — Tue, 28 Oct 2014 21:49:45 +0000

Neutron Reflection (NR) is a highly credible, non-destructive technique used to study the interfaces. It helps to define the interface properties between different material layers, and these layers can be studied with the resolution of the order of angstroms. By measuring the position of interfaces between different materials, the thickness of the layer can be obtained while the density and the contained molecular species of the studied layer can be figured out from the neutron scattering length density distribution profile . NR offers greater structural resolution, particularly with the help of deuterium labeling to lipid, solvent and lead polymeric nano-object.

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Spectroscopic ellipsometry (SE)

Daniela Ciumac — Mon, 27 Oct 2014 23:59:20 +0000

Ellipsometry is an optical technique for analyzing and characterizing an interface or a layer between two surfaces. The method is based on the measure of the change of polarization as light interacts with the material structure of interest . Ellipsometry is a very used technique, with applications in various fields, as semiconductor physics, microelectronics, biology, biophysics, telecommunications, from basic research to industrial applications . In biophysics, this method can be used to study interfacial films at solid-water interface, the structure and dynamics of interfacial adsorption of proteins, the interfacial assembly of lipids, and the interactions between various nano-objects and lipid

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Dual polarization interferometry (DPI)

Daniela Ciumac — Mon, 27 Oct 2014 23:43:48 +0000

Dual polarization interferometry is a relatively new technique, which explores the molecular layers adsorbed to the surface of a waveguide by means of an electromagnetic evanescent wave of a laser beam; it measures the refractive index and the thickness of very thin films, and is also used to study the protein adsorption at solid/water interface. Furthermore, if the refractive index of the studied film is fixed, the birefringence can be observed quantitatively so that the anisotropy of the film can be analyzed. DPI is a quantitative and real-time technique with the dimensional resolution of the order of angstroms .

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Langmuir trough

Daniela Ciumac — Mon, 27 Oct 2014 23:30:23 +0000

The Langmuir trough is a laboratory apparatus used to create and characterize single molecule thick films by controlling the packing density of the molecules. The idea of a Langmuir film was first proposed by Dr. Irving Langmuir in 1917, when he created a single-molecule thin film on water surface. When a monolayer is fabricated at the gas-liquid or liquid-liquid interface, the film is named Langmuir film (fig.1a). Besides the classical Langmuir troughs, there are also the Langmuir-Blodgett (LB) and Langmuir-Schaefer (LS) techniques that allow depositing the Langmuir film on a solid surface, through vertical (LB) or horizontal depositions (LS) .

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ESR9-M: Investigation of interaction of membrane-lytic molecules with lipid monolayer

Daniela Ciumac — Thu, 05 Dec 2013 15:14:29 +0000

Supported bilayers and vesicles Objectives The intention of this project is to obtain experimental information and feedback for system improvement of nano-objects interacting with model membranes (supported bilayers and vesicles). to apply a combination of techniques including neutron reflectivity, SANS (Manchester, Unilever), AFM, TEM (Strasbourg, Manchester) to characterise supported lipid bilayers and model vesicles; to investigate how different nano-objects (polymers, block copolymers, short peptide aggregates, CNTs, nanoparticles) interact with lipid bilayers; to undertake selected studies of the interactions with therapeutic complexes to identify the vectors that provide optimal therapeutic delivery with minimal cytotoxicity. Tasks and methodology Interaction of nano-objects with

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