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International audience; Understanding the dynamic of in-depth migration and retention of hydrogen in Carbon Fiber Composites (CFCs) used as plasma facing material has for long time been complicated by the lack on in situ analyzing tools. A dedicated experimental setup coupling an ECR ion source to the Saclay nuclear microprobe was developed to expose CFC samples to deuterium implantation at 200–300eV and fluences from 1022 to 1024D/m2, and then to perform in situ μNRA analysis for 3D deuterium profiles. Once the technique proven as non perturbative, we observed that while we have a homogeneous, fluence-independent deuterium concentration at the surface, the in-bulk deuterium is concentrated in the porosities and increases with the incident fluence, up to very large depth (500μm). For the first time, it was evidenced that these two distinct mechanisms are simultaneous to the implantation. D profiles evolve very little with in-vacuum storage time.

When bioactive glasses are in contact with living tissues, several physico-chemical reactions (dissolution, precipitation…) take place at the material / bone interface, and lead to the formation of a phosphocalcic layer, whose composition is close to the mineral phase of the bone (hydroxyapatite). The apatite layer is used as a mineralization site for bone cells and finally allows an intimate bond between the bioactive glass and osseous tissues. This bond is typical of bioactivity, which can be modulated through several parameters of the glass, like composition in major and trace elements or textural properties (specific surface, porosity).In this context, we elaborated bioactive glasses in binary (SiO2-CaO) and ternary (SiO2-CaO-P2O5) systems. Glasses have been doped with zinc and magnesium ions through the sol-gel route. Thanks to the use of surfactants, we obtained mesostructured glasses. Finally, by using inverse opal method, organized macroporous glasses have been synthesized. The influence of these parameters on the reactivity of glasses in contact with a biological medium (DMEM) has been mainly studied by techniques using micro-ion beams. The X-ray emission induced by charged particles (PIXE) combined with Rutherford backscattering spectrometry (RBS) has indeed demonstrated clear effects on the kinetics, the amplitude, and the spatial distribution of the physico-chemical reactions.; Lorsque les verres bioactifs entrent en contact avec des tissus vivants, une série de réactions physico-chimiques (dissolution, précipitation...) ont lieu à l’interface matériau / os, et conduisent à la formation d’une couche phosphocalcique, dont la composition est proche de la phase minérale de l’os (hydroxyapatite). La couche d’apatite sert de site de minéralisation pour les cellules osseuses, ce qui permet in fine un lien intime entre le verre bioactif et les tissus osseux. Ce lien est caractéristique de la bioactivité, qui peut être modulée via plusieurs paramètres du verre comme la composition en éléments majeurs et traces ou les propriétés texturales (surface spécifique, porosité).Dans ce contexte, nous avons élaboré des verres bioactifs dans des systèmes binaires (SiO2-CaO) et ternaires (SiO2-CaO-P2O5). Ces verres ont été dopés en ions zinc et magnésium via la voie sol-gel. Grâce à l'emploi de tensioactifs, nous avons obtenu des verres mésostructurés. Enfin, en utilisant des méthodes dites « d’opale inverse », des verres à macroporosité organisée ont été synthétisés. L'influence de ces paramètres sur la réactivité des verres au contact d’un milieu biologique (DMEM) a principalement été étudiée par des techniques utilisant des microfaisceaux d'ions. L'émission X induite par particules chargées (PIXE) combinée à la spectrométrie de rétrodiffusion Rutherford (RBS) a en effet démontré des effets évidents sur la cinétique, l'amplitude et la distribution spatiale des réactions physico-chimiques.

When bioactive glasses are in contact with living tissues, several physico-chemical reactions (dissolution, precipitation…) take place at the material / bone interface, and lead to the formation of a phosphocalcic layer, whose composition is close to the mineral phase of the bone (hydroxyapatite). The apatite layer is used as a mineralization site for bone cells and finally allows an intimate bond between the bioactive glass and osseous tissues. This bond is typical of bioactivity, which can be modulated through several parameters of the glass, like composition in major and trace elements or textural properties (specific surface, porosity).In this context, we elaborated bioactive glasses in binary (SiO2-CaO) and ternary (SiO2-CaO-P2O5) systems. Glasses have been doped with zinc and magnesium ions through the sol-gel route. Thanks to the use of surfactants, we obtained mesostructured glasses. Finally, by using inverse opal method, organized macroporous glasses have been synthesized. The influence of these parameters on the reactivity of glasses in contact with a biological medium (DMEM) has been mainly studied by techniques using micro-ion beams. The X-ray emission induced by charged particles (PIXE) combined with Rutherford backscattering spectrometry (RBS) has indeed demonstrated clear effects on the kinetics, the amplitude, and the spatial distribution of the physico-chemical reactions.; Lorsque les verres bioactifs entrent en contact avec des tissus vivants, une série de réactions physico-chimiques (dissolution, précipitation...) ont lieu à l’interface matériau / os, et conduisent à la formation d’une couche phosphocalcique, dont la composition est proche de la phase minérale de l’os (hydroxyapatite). La couche d’apatite sert de site de minéralisation pour les cellules osseuses, ce qui permet in fine un lien intime entre le verre bioactif et les tissus osseux. Ce lien est caractéristique de la bioactivité, qui peut être modulée via plusieurs paramètres du verre comme la composition en éléments majeurs et traces ou les propriétés texturales (surface spécifique, porosité).Dans ce contexte, nous avons élaboré des verres bioactifs dans des systèmes binaires (SiO2-CaO) et ternaires (SiO2-CaO-P2O5). Ces verres ont été dopés en ions zinc et magnésium via la voie sol-gel. Grâce à l'emploi de tensioactifs, nous avons obtenu des verres mésostructurés. Enfin, en utilisant des méthodes dites « d’opale inverse », des verres à macroporosité organisée ont été synthétisés. L'influence de ces paramètres sur la réactivité des verres au contact d’un milieu biologique (DMEM) a principalement été étudiée par des techniques utilisant des microfaisceaux d'ions. L'émission X induite par particules chargées (PIXE) combinée à la spectrométrie de rétrodiffusion Rutherford (RBS) a en effet démontré des effets évidents sur la cinétique, l'amplitude et la distribution spatiale des réactions physico-chimiques.

N° d'ordre : DU 1763, EDSF : 567; The study of bioactive glasses is a multi-field area of research aiming at a major goal: the development of new gen-eration biomaterials that would be able to bond with host tissues through the formation of a strong interfacial bond, together with helping the body heal itself through the stimulation of specific cellular responses. Thus clinical applica-tions of bioactive glasses mainly concern dental surgery and orthopaedics, for filling osseous defects. For this purpose, we have elaborated bioactive glasses in the binary SiO2–CaO system, ternary SiO2–CaO–P2O5 system, and for the first time, to our knowledge, strontium-doped SiO2–CaO–SrO and SiO2–CaO–P2O5–SrO glasses. The materials were elaborated using the sol-gel process, which allowed the synthesis of nanoporous materials with great purity and homogeneity. The bioactivity of the glasses was clearly demonstrated in vitro: in contact with biological fluids, the whole lot of mate-rials were able to induce the formation of a Ca-P-Mg layer a few microns thick at their surface. Our work is characterized by the use of PIXE-RBS nuclear microprobes to study the bioactive glass/biological fluids interface. Thanks to these methods we obtained chemical maps that made possible the analysis of major and trace elements concentrations at the interface. Moreover, quantitative information regarding the local reactivity of glasses were acquired. These data are impor-tant to evaluate the kinetics and amplitude of the physico-chemical reactions involved in the bioactivity process. Thus, we highlighted that the binary glass is the highest reactive regarding the dissolution of the glassy matrix as well as the first appearance of the Ca-P rich layer. However the Ca/P atomic ratio calculated at the glass/biological fluids interface decreases slowly, indicating that the Ca-P-Mg layer encounters difficulties to be changed into a more stable apatitic phase. For the P-containing glasses, the dealkalinization of the matrix and the formation of the calcium phosphate layer are delayed. However, calculation of the interfacial Ca/P ratios along with supersaturation studies of the biological medium demonstrate that the Ca-P-Mg layer is quickly changed into an apatitic phase. Concerning the Sr-doped glasses, we highlighted that the dissolution of the material decreased and that the Ca-P-Mg layer was formed on a reduced depth. Nevertheless, according to the rapid decrease of the Ca/P ratio, there is evidence that the layer is more quickly changed into apatite. We also demonstrated that traces of Sr are both present at the glass/biological fluids interface and diffused in the biological medium. Knowing the positive effects of Sr on the cellular activity and on the bone modelling process, it might result in an improved bioactivity for the Sr-doped glasses in contact with a living system.; L'étude des verres bioactifs constitue un domaine de recherche pluridisciplinaire aux enjeux considérables : la mise au point d'une nouvelle génération de biomatériaux, capables de se lier avec les tissus receveurs, de former un lien interfacial fort et d'aider l'organisme à se soigner lui-même grâce à une action directe sur les cellules. Les applications concernent particulièrement le comblement de défauts osseux en chirurgies orthopédique et dentaire. Dans cette optique, nous avons élaboré plusieurs verres bioactifs dans des systèmes de composition binaire SiO2–CaO, ternaires SiO2–CaO–P2O5 , et pour la première fois à notre connaissance des verres contenant du strontium SiO2–CaO–SrO et SiO2–CaO–P2O5–SrO. L'utilisation du procédé sol-gel comme voie de synthèse des verres bioactifs s'est révélée avantageuse, car permettant l'élaboration de matériaux nanoporeux, de grande pureté et homogénéité. La bioactivité in vitro des verres est avérée : au contact d'un milieu biologique, tous les matériaux élaborés induisent la formation d'une couche Ca-P-Mg sur une profondeur de quelques microns à leur surface. Nos travaux se distin-guent par l'utilisation des microsondes nucléaires PIXE-RBS pour la caractérisation de l'interface verre bioactif/milieu biologique; leur emploi a permis de réaliser des cartographies chimiques rendant possible l'étude des gradients de concentrations en éléments majeurs et traces à l'interface. De plus, des informations quantitatives sur la réactivité locale des verres ont été acquises. Ces données sont importantes pour évaluer les cinétiques et l'amplitude des réac-tions physico-chimiques impliquées dans le processus de bioactivité. Nous avons ainsi mis en évidence que le verre binaire est le plus prompt à réagir en ce qui concerne la dissolution de la matrice vitreuse et l'apparition de la couche riche en Ca et en P. Toutefois la plus lente décroissance du rapport Ca/P à l'interface verre/milieu biologique indique que la couche Ca-P-Mg éprouve des difficultés à évoluer vers une phase apatitique. Pour les verres contenant du phosphore, la désalcalinisation de la matrice et la formation de la cou-che phosphocalcique sont retardées ; cependant le calcul du rapport Ca/P à l'interface et le suivi de l'état de saturation du milieu biologique montrent que la couche Ca-P-Mg se développe plus rapidement en une couche de type apatiti-que. Concernant les verres dopés en Sr, nous avons démontré que leur capacité de dissolution est amoindrie et que la couche Ca-P-Mg se forme sur une profondeur plus réduite. Néanmoins, la couche évolue plus promptement en apa-tite d'après la rapide décroissance du rapport Ca/P. Nous avons également obtenu des preuves de la présence de Sr à l'interface verre/liquide et de la diffusion de cet élément dans le milieu biologique sous forme de traces. Grâce aux effets bénéfiques du strontium sur l'activité cellulaire et sur le cycle de remodelage osseux, ceci pourrait résulter en une bioactivité grandement améliorée pour les verres dopés en Sr en milieu vivant.

The study of bioactive glasses is a multi-field area of research aiming at a major goal: the development of new generation biomaterials that would be able to bond with host tissues through the formation of a strong interfacial bond, together with helping the body heal itself through the stimulation of specific cellular responses. Thus clinical applications of bioactive glasses mainly concern dental surgery and orthopaedics, for filling osseous defects. For this purpose, we have elaborated bioactive glasses in the binary SiO2-CaO system, ternary SiO2-CaO-P2O5 system, and for the first time, to our knowledge, strontium-doped SiO2-CaO-SrO and SiO2-CaO-P2O5-SrO glasses. The materials were elaborated using the sol-gel process, which allowed the synthesis of nanoporous materials with great purity and homogeneity. The bioactivity of the glasses was clearly demonstrated in vitro: in contact with biological fluids, the whole lot of materials were able to induce the formation of a Ca-P-Mg layer a few microns thick at their surface. Our work is characterized by the use of PIXE-RBS nuclear microprobes to study the bioactive glass/biological fluids interface. Thanks to these methods we obtained chemical maps that made possible the analysis of major and trace elements concentrations at the interface. Moreover, quantitative information regarding the local reactivity of glasses were acquired. These data are important to evaluate the kinetics and amplitude of the physico-chemical reactions involved in the bioactivity process. Thus, we highlighted that the binary glass is the highest reactive regarding the dissolution of the glassy matrix as well as the first appearance of the Ca-P rich layer. However the Ca/P atomic ratio calculated at the glass/biological fluids interface decreases slowly, indicating that the Ca-P-Mg layer encounters difficulties to be changed into a more stable apatitic phase. For the P-containing glasses, the dealkalinization of the matrix and the formation of the calcium phosphate layer are delayed. However, calculation of the interfacial Ca/P ratios along with supersaturation studies of the biological medium demonstrate that the Ca-P-Mg layer is quickly changed into an apatitic phase. Concerning the Sr-doped glasses, we highlighted that the dissolution of the material decreased and that the Ca-P-Mg layer was formed on a reduced depth. Nevertheless, according to the rapid decrease of the Ca/P ratio, there is evidence that the layer is more quickly changed into apatite. We also demonstrated that traces of Sr are both present at the glass/biological fluids interface and diffused in the biological medium. Knowing the positive effects of Sr on the cellular activity and on the bone modelling process, it might result in an improved bioactivity for the Sr-doped glasses in contact with a living system.; Les verres bioactifs permettent de combler les défauts osseux lors d'applications cliniques. Nous avons élaboré par sol-gel plusieurs verres bioactifs, parmi lesquels des verres dopés en Sr. La bioactivité des verres est avérée : au contact d'un milieu biologique, une couche Ca-P se forme rapidement en surface de nos matériaux. La caractérisation de l'interface verre/ milieu biologique par faisceau d'ions démontre que le verre binaire est le plus rapide en ce qui concerne la dissolution de la matrice et l'apparition de la couche Ca-P. Pour les verres contenant du P, ces phénomènes sont retardés, mais la couche Ca-P-Mg se développe vite en une couche apatitique. Pour les verres dopées en Sr, la couche Ca-P-Mg se forme sur une profondeur réduite. Néanmoins elle évolue plus vite en apatite. De plus la présence de Sr à l'interface verre/ liquide et dans le milieu biologique pourrait résulter, grâce aux effets bénéfiques du Sr sur l'activité cellulaire, en une bioactivité améliorée in vivo

Since its development in the early 1990’s, ion beam induced charge (IBIC) microscopy has found widespread applications in many microprobe laboratories for the analysis of microelectronic devices, dislocations, semiconductor radiation detectors, semi-insulating materials, high power transistors, charge-coupled arrays, solar cells, light emitting diodes, and in conjunction with Single Event Upset imaging. Several modalities of the techniques have been developed, such as lateral IBIC and time-resolved IBIC. The theoretical model of IBIC generation and collection has developed from a one-dimensional model of charge drift and diffusion to a detailed model of the motion of ion charge carriers in semiconductors and insulators. This paper reviews the current state-of-the-art of IBIC theory and applications.

The increased modularity in the total hip arthroplasty (THA) allows adapting the prosthesis to the specific anatomical characteristics of each patient. However, the advantages of the modular THA are shadowed by the increased number of prosthesis failures observed in patients. The presence of junction in modular THA may increase its risk of mechanical failure. Moreover, the micro movements between neck and stem could lead to the production of metallic debris which may cause tissue inflammation and unsealing of prosthesis due to osseous dissolution. It is necessary to understand the mechanism of dispersion of the metal particles from the prosthesis into the tissue. Techniques currently applied in hospitals, such as X-ray scans or optical tissue microscopies, are able to distinguish metal particles, but unable to identify their specific metallic origin. In this work, within the TissueMaps project, we have proved that Proton Induced X-ray Emission (PIXE) is able to provide the distribution and elemental composition of particles from the prosthesis into the pseudo capsular tissue samples (near the femoral head) and identify the features observed under optical microscopy, in a case of broken neck prosthesis.

Hip prosthesis replacement is one of the most frequent and costly treatments in developed countries. The increased number of patients and the insufficient understanding of physiological processes leading to prosthesis failure make necessary the use of complementary techniques to better understand the degradation of implants [1]. We present two cases of prosthesis failure: Patient 2, with a modular hip prosthesis made of TiAlV alloy (Profemur®), presents a broken neck; and Patient 7, with a Ceramic on Ceramic articulation made of zirconia toughtened alumina (Biolox® Delta), presents a broken acetabular inlay. The presence of metallic debris coming from the prosthesis has been studied by using Particle-Induced X-ray Emission (PIXE). This technique combines high elemental sensitivity (detection limit 0,1 ppm) with high lateral resolution (600 nm) [2]. The analysis was performed with the 2 MV tandem accelerator available at Jožef Stefan Institute (JSI) [3]. [1] Fokter SK, et al., Acta Orthopaedica, 87(2), p.197-202, 2016. [2] P. Vavpetič et al., Nuclear Instruments and Methods in Physics Research B, vol. 306, pp. 140-143, 2013. [3] Primoz Pelicon et al., Nuclear Instruments and Methods in Physics Research B, vol. 332, pp. 229-233, 2014, This project, TISSUEMAPS, has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 799182.

Hip prosthesis replacement is one of the most frequent and costly treatments in developed countries. The increased number of patients and the insufficient understanding of physiological processes leading to prosthesis failure make necessary the use of complementary techniques to better understand the degradation of implants [1]. We present two cases of prosthesis failure: Patient 2, with a modular hip prosthesis made of TiAlV alloy (Profemur®), presents a broken neck; and Patient 7, with a Ceramic on Ceramic articulation made of zirconia toughtened alumina (Biolox® Delta), presents a broken acetabular inlay. The presence of metallic debris coming from the prosthesis has been studied by using Particle-Induced X-ray Emission (PIXE). This technique combines high elemental sensitivity (detection limit 0,1 ppm) with high lateral resolution (600 nm) [2]. The analysis was performed with the 2 MV tandem accelerator available at Jožef Stefan Institute (JSI) [3]. [1] Fokter SK, et al., Acta Orthopaedica, 87(2), p.197-202, 2016. [2] P. Vavpetič et al., Nuclear Instruments and Methods in Physics Research B, vol. 306, pp. 140-143, 2013. [3] Primoz Pelicon et al., Nuclear Instruments and Methods in Physics Research B, vol. 332, pp. 229-233, 2014

Hip prosthesis replacement is one of the most frequent and costly treatments in developed countries. The increased number of patients and the insufficient understanding of physiological processes leading to prosthesis failure make necessary the use of complementary techniques to better understand the degradation of implants [1]. We present two cases of prosthesis failure: Patient 2, with a modular hip prosthesis made of TiAlV alloy (Profemur®), presents a broken neck; and Patient 7, with a Ceramic on Ceramic articulation made of zirconia toughtened alumina (Biolox® Delta), presents a broken acetabular inlay. The presence of metallic debris coming from the prosthesis has been studied by using Particle-Induced X-ray Emission (PIXE). This technique combines high elemental sensitivity (detection limit 0,1 ppm) with high lateral resolution (600 nm) [2]. The analysis was performed with the 2 MV tandem accelerator available at Jožef Stefan Institute (JSI) [3]. [1] Fokter SK, et al., Acta Orthopaedica, 87(2), p.197-202, 2016. [2] P. Vavpetič et al., Nuclear Instruments and Methods in Physics Research B, vol. 306, pp. 140-143, 2013. [3] Primoz Pelicon et al., Nuclear Instruments and Methods in Physics Research B, vol. 332, pp. 229-233, 2014, This project, TISSUEMAPS, has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 799182.

Hip prosthesis replacement is one of the most frequent and costly treatments in developed countries. The increased number of patients and the insufficient understanding of physiological processes leading to prosthesis failure make necessary the use of complementary techniques to better understand the degradation of implants [1]. We present two cases of prosthesis failure: Patient 2, with a modular hip prosthesis made of TiAlV alloy (Profemur®), presents a broken neck; and Patient 7, with a Ceramic on Ceramic articulation made of zirconia toughtened alumina (Biolox® Delta), presents a broken acetabular inlay. The presence of metallic debris coming from the prosthesis has been studied by using Particle-Induced X-ray Emission (PIXE). This technique combines high elemental sensitivity (detection limit 0,1 ppm) with high lateral resolution (600 nm) [2]. The analysis was performed with the 2 MV tandem accelerator available at Jožef Stefan Institute (JSI) [3]. [1] Fokter SK, et al., Acta Orthopaedica, 87(2), p.197-202, 2016. [2] P. Vavpetič et al., Nuclear Instruments and Methods in Physics Research B, vol. 306, pp. 140-143, 2013. [3] Primoz Pelicon et al., Nuclear Instruments and Methods in Physics Research B, vol. 332, pp. 229-233, 2014

The metallic-associated adverse local tissue reactions (ALTR) and events accompanying worn-broken implant materials are still poorly understood on the subcellular and molecular level. Current immunohistochemical techniques lack spatial resolution and chemical sensitivity to investigate causal relations between material and biological response on submicron and even nanoscale. In our study, new insights of titanium alloy debris-tissue interaction were revealed by the implementation of label-free high-resolution correlative microscopy approaches. We have successfully characterized its chemical and biological impact on the periprosthetic tissue obtained at revision surgery of a fractured titanium-alloy modular neck of a patient with hip osteoarthritis. We applied a combination of photon, electron and ion beam micro-spectroscopy techniques, including hybrid optical fluorescence and reflectance micro-spectroscopy, scanning electron microscopy (SEM), Energy dispersive X-ray Spectroscopy (EDS), helium ion microscopy (HIM) and micro-particle-induced X-ray emission (micro-PIXE). Micron-sized wear debris were found as the main cause of the tissue oxidative stress exhibited through lipopigments accumulation in the nearby lysosome. This may explain the indications of chronic inflammation from prior histologic examination. Furthermore, insights on extensive fretting and corrosion of the debris on nm scale and a quantitative measure of significant Al and V release into the tissue together with hydroxyapatite-like layer formation particularly bound to the regions with the highest Al content were revealed. The functional and structural information obtained at molecular and subcellular level contributes to a better understanding of the macroscopic inflammatory processes observed in the tissue level. The established label-free correlative microscopy approach can efficiently be adopted to study any other clinical cases related to ALTR.