References of "Thiry, P. A"
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See detailInfluence of DNA condensation state on transfection efficiency in DNA/polymer complexes: An AFM and DLS comparative study
Volcke, C.; Pirotton, S.; Grandfils, Christian ULg et al

in Journal of Biotechnology (2006), 125(1), 11-21

Atomic force microscopy (AFM) is used to describe the formation process of polymer/DNA complexes. Two main objectives of this research are presented. The first one is to apply AFM as an effective tool to ... [more ▼]

Atomic force microscopy (AFM) is used to describe the formation process of polymer/DNA complexes. Two main objectives of this research are presented. The first one is to apply AFM as an effective tool to analyse DNA molecules and different polycation/DNA complexes in order to evaluate their degree of condensation (size and shape). The other one is to search for a relationship between the condensation state of DNA and its transfection efficiency. In this study, linear methacrylate based polymers and globular SuperFect polymers are used in order to induce DNA condensation. Ternary complexes, composed of methacrylate based polymers and polyethylene glycol (PEG)-based copolymers, are also investigated. AFM allows us to confirm good condensation conditions and relate them (or not) to transfection efficiencies. These AFM results (obtained after drying in air) are compared with measurements deduced from Dynamic Light Scattering (DLS) experiments performed in water. This comparison allowed us to identify the structural modifications resulting from deposition on the mica surface. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailInfluence of the metal electronic properties on the sum-frequency generation spectra of dodecanethiol self-assembled monolayers on Pt (111), Ag (111) and Au (111) single crystals
Dreesen, Laurent ULg; Humbert, Christophe; Celebi, M. et al

in Applied Physics B : Lasers & Optics (2002), 74

Infrared-visible sum-frequency generation (SFG) spectroscopy is performed at different visible wavelengths between 450 and 650 nm in order to investigate the interaction between metallic substrates (Pt ... [more ▼]

Infrared-visible sum-frequency generation (SFG) spectroscopy is performed at different visible wavelengths between 450 and 650 nm in order to investigate the interaction between metallic substrates (Pt, Ag and Au) and 1-dodecanethiol self-assembled monolayers. We show that such measurements provide a means to study the electronic properties of metals as well as the interference phenomena between the SFG signals from the adsorbate and the substrate. The common features of the three interfaces are the vibration modes of the terminal methyl groups. However, these resonances appear as peaks for Pt (111) and as dips in the case of Ag (111). Their shape is not modified when the visible wavelength is tuned between 450 and 650 nm. Moreover, the metal sum-frequency generation contribution is slightly modified in that spectral range. For Au (111) samples, the sum-frequency generation spectrum drastically evolves with the visible wavelength: the peak resonant sum-frequency generation signal at 450 nm becomes rather dip-shaped at 650 nm. The non-linear response of gold is also enhanced when the wavelength associated with the sum-frequency process is close to 480 nm. These results are interpreted on the basis of the metal electronic properties that are responsible for the non-resonant contribution to the SFG signal. [less ▲]

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