Anouk Galtayries - Academia.edu (original) (raw)

Papers by Anouk Galtayries

This study investigated the in vitro effects of bioactive titanium surfaces on osteoblast differe... more This study investigated the in vitro effects of bioactive titanium surfaces on osteoblast differentiation. Three titanium substrates were tested: a commercially pure titanium (Cp Ti), an alkali-and heat-treated titanium (AH Ti), and an apatite-formed titanium (Ap Ti) generated by soaking AH Ti in a simulated body fluid. Chemical evaluation of the surface reactivity was analysed at nanometre scale by X-ray photoelectron spectroscopy (XPS), and at micrometre scale by energy dispersive Xray microanalysis (EDX). It showed that the estimated proportion of the surface covered by adsorbed serum proteins differed between the three substrates and confirmed the bioactivity of AH Ti, illustrated by surface calcium and phosphate deposition when immersed in biological fluids. Mouse calvaria osteoblasts were cultured on the substrates for 15 days with no sign of cytotoxicity. Enzyme immunoassay and Real-Time RT-PCR were used to follow osteoblast differentiation through the production of osteocalcin (OC) and expression of several bone markers. At day 15, a significant up-regulation of Runx2, Osx, Dlx5, ALP, BSP, OC and DMP1 mRNA levels associated with an increase of OC production were observed on AH Ti and Ap Ti when compared to Cp Ti. These results suggest that bioengineered titanium has a great potential for dental applications in enhancing osseointegration.

Journal of Physics D, Apr 9, 2014

Recent advances in vacuum sciences and applications are reviewed. Novel optical interferometer ca... more Recent advances in vacuum sciences and applications are reviewed. Novel optical interferometer cavity devices enable pressure measurements with ppm accuracy. The innovative dynamic vacuum standard allows for pressure measurements with temporal resolution of 2 ms. Vacuum issues in the construction of huge ultra-high vacuum devices worldwide are reviewed. Recent advances in surface science and thin films include new phenomena observed in electron transport near solid surfaces as well as novel results on the properties of carbon nanomaterials. Precise techniques for surface and thin-film characterization have been applied in the conservation technology of cultural heritage objects and recent advances in the characterization of biointerfaces are presented. The combination of various vacuum and atmospheric-pressure techniques enables an insight into the complex phenomena of protein and other biomolecule conformations on solid surfaces. Studying these phenomena at solid-liquid interfaces is regarded as the main issue in the development of alternative techniques for drug delivery, tissue engineering and thus the development of innovative techniques for curing cancer and cardiovascular diseases. A review on recent advances in plasma medicine is presented as well as novel hypotheses on cell apoptosis upon treatment with gaseous plasma. Finally, recent advances in plasma nanoscience are illustrated with several examples and a roadmap for future activities is presented.

Surface and Interface Analysis, May 1, 1996

ABSTRACT

Journal of The Electrochemical Society, Sep 1, 2010

The pitting corrosion of Al-Cu thin film alloys was investigated using samples that were heat tre... more The pitting corrosion of Al-Cu thin film alloys was investigated using samples that were heat treated in air to form through-thickness Al2Cu particles within an Al-0.5%Cu matrix. Time-of-Flight SIMS (ToF-SIMS) analysis revealed Cu-rich regions 250 - 800 nm in lateral extent near the metal/oxide interface. Following exposure that generated pitting corrosion, secondary electron, secondary ion, and AFM images showed pits

HAL (Le Centre pour la Communication Scientifique Directe), May 3, 2015

HAL (Le Centre pour la Communication Scientifique Directe), Nov 20, 2015

... In all cases, the thicknesses are given with an accuracy of + 10%. The primary ions for RBS a... more ... In all cases, the thicknesses are given with an accuracy of + 10%. The primary ions for RBS analyses were He + ions with energy of 1 MeV obtained from a Van de Graaff accelerator at normal incidence. The samples are analyzed at 165 ° back scattering angle. ...

Proceedings of SPIE, May 7, 2009

Optics Express, Sep 3, 2010

OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information), Sep 1, 2009

Electrochimica Acta, 2006

The adsorption of bovine serum albumin (BSA), and its influence on the electrochemical behaviour ... more The adsorption of bovine serum albumin (BSA), and its influence on the electrochemical behaviour in deaerated 0.05 M H 2 SO 4 solution of a ferritic stainless steel, Fe-17Cr, was studied by electrochemical methods (time dependence of the corrosion potential E cor , polarization curves, EIS) and surface analysis techniques (PM-IRRAS, XPS). The electrochemical measurements show a corrosion inhibition by the BSA at E cor. The charge transfer resistance decreases and hence the corrosion current of the alloy increases with immersion time at E cor , but this phenomenon is much less marked in the presence of BSA. Impedance measurements performed after passivation of the alloy at 0 V versus SSE show that the presence of protein has no effect on the electrochemical behaviour of the passivated alloy surface. Surface analysis of the stainless steel samples by PM-IRRAS and XPS shows that chemically intact BSA molecules are adsorbed on the surface at E cor and 0 V. The amount of adsorbed BSA is quite similar at both potentials. All these results demonstrate that the adsorption of BSA takes place on the Fe-17Cr surface both at the corrosion potential and in the passive region, and the BSA has a corrosion inhibition effect when the surface is not fully passivated.

Surface and Interface Analysis, Sep 14, 2018

Colloids and Surfaces A: Physicochemical and Engineering Aspects, Dec 1, 2013

ABSTRACT tSurface characterisation of alloys before and after their interaction with proteins all... more ABSTRACT tSurface characterisation of alloys before and after their interaction with proteins allows a more rationaldesign of biomaterials. In this work, fibronectin adsorption on a Ti-based quasicrystals-forming alloy wasstudied by X-ray photoelectron spectroscopy (XPS) and compared to those obtained on pure titaniumsubstrates (cp Ti). Different fibronectin (Fn) solution concentrations were tested in interaction with thequasi-crystalline/amorphous Ti45Zr38Ni17composite. N 1s, C 1s, Ti 2p, Zr 3d and Ni 2p core level spectrawere systematically recorded. The results indicate that fibronectin is chemically adsorbed on Ti45Zr38Ni17as well as on cp Ti. The alloy surface composition and oxide thickness are not significantly changed inpresence of the adsorbed protein. Data on the elemental distribution in the alloy surface obtained byXPS were completed by depth profiling with Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS). Surface saturation is clearly reached for Fn solution concentrations of 100–150 �g mL−1for bothsurfaces. On the plateau, the equivalent protein thickness is 6 nm for Ti45Zr38Ni17and 8 nm for cp Ti, bothcorresponding to one fibronectin monolayer. These results are in accordance with previous observationson osteoblasts adhesion, confirming the biocompatibility of Ti45Zr38Ni17. However, quasicrystals do notseem to influence the alloy surface reactivity.

Journal of Electron Spectroscopy and Related Phenomena, Oct 1, 1997

By combining XPS and measurements of surface potential variation Acb, the surface evolution of po... more By combining XPS and measurements of surface potential variation Acb, the surface evolution of polycrystalline Mo samples has been studied during several processes of oxidation and sulphidation from room temperature up to 400°C. The chemical states of Mo, O and S have been identified from their core level binding energies, whereas the Acb variation reflects changes in the work function during formation of the films. Oxidation by 02 at 400°C produces an oxygen-deficient MoO3 film which is further transformed by immersion in water with the formation of lower Mo oxidation states (mainly Mo w and MoUn). Direct immersion of the metal in water results in the progressive growth of a highly hydroxylated and hydrated oxide film with the predominance of a MoO2 structure after prolonged immersion. Thick Mo sulphide films (thickness > 112 A) are obtained by immersion of the foil in a thiomolybdate solution and further UHV annealing or by H2S sulphidation of the preoxidized metal. In the sulphided films, the presence of both S 2-and S~-species has been detected, the distribution of which influences the A~ variation according to: AcI , (mV) = 550-13.75[S~-(%)]. It has also been found that the A~ values of the films decrease in the order: A~[MoO3] > AdP[MoS2] > A~[MoS3] > A,I,[Mo°].

Physical Chemistry Chemical Physics, 1999

HAL (Le Centre pour la Communication Scientifique Directe), Feb 14, 2010

Reaction Kinetics and Catalysis Letters, Jul 1, 1996

Journal of Electron Spectroscopy and Related Phenomena, 1999

Dry O 2 oxidation up to 400ЊC, water immersion at room temperature or H 2 S sulphidation at 400ЊC... more Dry O 2 oxidation up to 400ЊC, water immersion at room temperature or H 2 S sulphidation at 400ЊC forms oxide or sulphide films on polycrystalline Co and Ni foils. X-ray photoelectron spectra (XPS) of the Co 2p and Ni 2p core levels and valence band (VB) structure changes allow the identification of the chemical state of such films and their electronic properties. They are compared with the films obtained on Mo in similar conditions. Ni appears less reactive than Co during O 2 or water oxidation and is considered as a more noble metal. Dry oxidation mainly induces CoO while water immersion induces formation of CoO(OH). For Ni, phases like Ni 2 O 3 , Ni(OH) 2 and/or NiO(OH) are the most probable products, respectively. H 2 S sulphidation always produces a sulphur-rich Co or Ni phase. The VB response to sulphidation of the three studied metals shows that Co or Ni sulphides are potential electron-donors to MoS 2. Such results are relevant to the synergy observed in hydrotreating catalysis with these sulphides.

Surface and Interface Analysis, Mar 1, 1995

The first steps of H2S adsorption have been studied on polycrystalline copper samples, which are ... more The first steps of H2S adsorption have been studied on polycrystalline copper samples, which are more relevant to industrial copper samples than to single‐crystal surfaces. The tools for characterization are ultrahigh vacuum spectroscopic methods, such as x‐ray photoelectron and ion scattering spectroscopies. The H2S adsorption on metallic copper and on the corresponding Cu2O and CuO oxides is dissociative and highly dependent on the chemical nature of the exposed surface rather than on the temperature, from room temperature up to 623 K. In our conditions, Cuo sulphidation deals with the top Cuo layer whereas two to three oxide surface monolayers are modified at H2S saturation. The results on oxides are interpreted by an oxygen/sulphur replacement mechanism following the dissociative adsorption. Contaminated copper surfaces by phenanthrene or H2O treatments are hardly sulphided. As far as surface reactivity is concerned, the adsorbed sulphide species have been shown to be quite strongly bound to the different surface states tested in this work: only oxidative treatments induce desorbing products at 623 K.

Macromolecular Bioscience, Aug 8, 2023

The uncontrolled accumulation of biological materials on the surface of medical devices through p... more The uncontrolled accumulation of biological materials on the surface of medical devices through protein adsorption or cell adhesion causes adverse biological reactions in the living host system, leading to complications. In this study, poly(ethylene glycol) (PEG) was successfully grafted onto polyurethane surfaces by using a new strategy through a simple and efficient transurethanisation reaction. The PEG hydroxyl group was deprotonated and then reacted with the polyurethane surface to provide antiadhesive hydrophilic surfaces in a single step. Surface analysis techniques proved the grafting to be efficient and the formation of a hydrophilic polymeric layer at the surface of polyurethane. Biological assays showed that the surface modification induced lower protein adsorption, cell, platelet and bacterial adhesion than untreated surfaces, showing a potential for biomedical applications.This article is protected by copyright. All rights reserved