X-ray Fluorescence Beamline Research Articles

Analysis of Ti nanolayers irradiated with Xeq＋ ions using synchrotron radiation based X-ray reflectometry

To characterize morphology and physicochemical properties of nanolayers the surface-sensitive X-ray spectroscopy techniques are often successfully applied. These techniques are still being developed in order to achieve better depth resolution and detection limits. In this article, we present measurements of morphology of Ti nanolayers (deposited on Si substrate) with thickness of 25 nm, 50 nm and 75 nm, unmodified and irradiated with Xeq＋ ions (where q is the charge state of the ion), which were carried out using synchrotron radiation (SR) based XRR technique. The nanolayers were irradiated with low-energy (of the order of hundreds of keV) highly charged Xeq＋ (q = 25, 30, 35) ions, at the Kielce EBIS facility (Jan Kochanowski University, Kielce, Poland). The SR-XRR measurements were performed at Elettra Synchrotron X-ray fluorescence beamline, using X-ray beam with energy of 6.0 keV. The obtained reflectivity curves were modelled by creating a structure consisting (from the bottom to the top) of silicon substrate (Si), main Ti layer, TiO2 layer, and TiO2(a) amorphous layer, with contamination of hydrocarbons, carboxylates or alkoxides. The experimental results obtained with the SR-XRR technique for the nanolayers, unmodified and irradiated with the Xeq＋, show the dependence of the TiO2 layers morphology on the Xe ions charge state. In the article the sample preparation, measurement using SR-XRR and the data analysis procedures are described in details and the advantages and disadvantages of the SR-XRR technique in the context of nanolayer studies are discussed.

Chromium and Zinc Speciation in Airborne Particulate Matter Collected in Ulaanbaatar, Mongolia, by X-Ray Absorption Near-edge Structure Spectroscopy

ABSTRACT This study examined the chemical speciation of atmospheric particulate matter (PM) samples collected in Ulaanbaatar, Mongolia. The health effects of atmospheric aerosol depend on the particles’ size distribution, elemental composition and chemical species as well as other factors, which vary according to the pollution sources and meteorological conditions. Employing the International Atomic Energy Agency (IAEA) supported X-ray fluorescence (XRF) beamline at Elettra Sincrotrone Trieste, Italy, we used a small incidence angle for the synchrotron emission radiation in this ultra-high-vacuum environment to analyze the fine and the coarse mode (PM2.5 and PM2.5-10, respectively) through X-ray absorption near-edge structure (XANES) spectroscopy, which was applied to the K-edges of the chromium (Cr) and zinc (Zn) in PM samples selected via energy-dispersive XRF (EDXRF) analysis for their high concentrations of these transition metals. The spectroscopic results identified trivalent chromium sulfate [Cr2(SO4)3] and chromium oxide (Cr2O3) compounds as the major chemical forms of Cr in both the coarse and the fine PM fraction. Furthermore, both fractions contained abundances of sulfate (ZnSO4) and silicate (Zn2SiO4) compounds, but only the fine mode contained Zn oxalate (ZnC2O4), whereas only the coarse mode contained Zn chloride (ZnCl2). These Cr and Zn species seemed to originate from local anthropogenic sources, e.g., combustion products or traffic-related resuspended road dust. Our findings, which are based on the first chemical speciation analysis from Ulaanbaatar, provide insight into the physiochemical characteristics of atmospheric aerosols as well as information on the potential sources of Cr and Zn species bound to fine and coarse PM.

Temporary implementation and testing of a confocal SR-[formula omitted]XRF system for bone analysis at the X-ray Fluorescence beamline at Elettra

The confocal μXRF spectrometer of Atominstitut (ATI) was transported and set up at the X-ray Fluorescence beamline at Elettra - Sincrotrone Trieste. It was successfully adjusted to the incoming beam (9.2 keV). Test measurements on a free-standing Cu wire were performed to determine the size of the focused micro-beam (non-confocal mode, 56 × 35 μm2) and the size of the confocal volume (confocal mode, 41×24×34μm2) for the Cu–Kα emission. In order to test the setup’s capabilities, two areas on different human bone samples were measured in confocal scanning mode. For one of the samples the comparison with a previous μ XRF measurement, obtained with a low power X-ray tube in the lab, is presented.

SR-TXRF analysis of trace elements in whole blood and heart of rats: effects of irradiation with low and high doses

In the last decades, studies showed that the exposure to low doses of ionizing radiation of the body could sense and activate the cell signaling pathways needed to respond to any induced cellular damage. This procedure reduces cell killing compared with a single dose of high radiation dose. Damage to the vasculature can affect the function of most body organs by restricting blood flow and oxygen to tissues; however, the heart and brain are of main concern. The precise relationship between long-term health effects and low-dose exposures remain poorly understood. Biological markers are powerful tools that can be used to determine dose- response relationships and to estimate risk, especially when dealing with, the effects of low dose exposures in humans. These markers should be specific, sensitive, as well as easy and fast to quantify. Various types of biologic specimens are potential candidates for identifying biomarkers but blood has the advantage of being minimally invasive to obtain. In this study, we propose to apply total reflection X-ray fluorescence to quantify possible chemical elemental concentration (sulfer, iron, zinc, potassium and calcium) changes in blood and heart tissues of Wistar rats after total body irradiation with low (0.1 Gy) and high (2.5 Gy) doses. The fluorescence measurements were carried out at the X-ray Fluorescence beamline in the Brazilian Synchrotron Light Laboratory. The results showed that the irradiated animals with low doses have significant alterations in blood and cardiac tissue when compared with animals that received high doses of radiation. Taken together the analysis of all the elements, we can observe that the radiation induced oxidative stress may be the leading cause for alteration of the elemental level in the studied samples.

An IAEA multi-technique X-ray spectrometry endstation at Elettra Sincrotrone Trieste: benchmarking results and interdisciplinary applications.

The International Atomic Energy Agency (IAEA) jointly with the Elettra Sincrotrone Trieste (EST) operates a multipurpose X-ray spectrometry endstation at the X-ray Fluorescence beamline (10.1L). The facility has been available to external users since the beginning of 2015 through the peer-review process of EST. Using this collaboration framework, the IAEA supports and promotes synchrotron-radiation-based research and training activities for various research groups from the IAEA Member States, especially those who have limited previous experience and resources to access a synchrotron radiation facility. This paper aims to provide a broad overview about various analytical capabilities, intrinsic features and performance figures of the IAEA X-ray spectrometry endstation through the measured results. The IAEA-EST endstation works with monochromatic X-rays in the energy range 3.7-14 keV for the Elettra storage ring operating at 2.0 or 2.4 GeV electron energy. It offers a combination of different advanced analytical probes, e.g. X-ray reflectivity, X-ray absorption fine-structure measurements, grazing-incidence X-ray fluorescence measurements, using different excitation and detection geometries, and thereby supports a comprehensive characterization for different kinds of nanostructured and bulk materials.

In situ analysis of Refractory Metal Nuggets in carbonaceous chondrites

Micrometre to sub-micrometre-scale alloys of platinum group elements (PGEs) known as Refractory Metal Nuggets (RMNs) have been observed in primitive meteorites. The Australian Synchrotron X-ray Fluorescence (XRF) beamline, in tandem with the Maia detector, allows rapid detection of PGEs in concentrations as low as 50–100ppm at 2μm resolution. Corroborating these analyses with traditional electron microscopy techniques, RMNs can be rapidly identified in situ within carbonaceous chondrites. These results dispute the assumption of most previous studies: that RMNs are unique to Ca–Al-rich inclusions (CAIs). We find that RMNs are, in fact, observed within all components of carbonaceous chondrites, such as the matrix, chondrules (consistent with observations from Schwander et al. (2015b) and Wang et al. (2007)), and sulphides; though the majority of RMNs are still found in CAIs. The chemistry of RMNs reveals a complex diversity of compositions, which nevertheless averages to CI chondrite abundance ratios. This implies that RMNs are the dominant, if not sole host phase for PGEs. One hundred and thirteen RMNs from this study are combined with reported compositions in the literature, and compared to condensation model compositions similar to Berg et al. (2009), RMNs derived experimentally by precipitation (Schwander et al., 2015a), host phase and host meteorite. Comparisons reveal only weak correlations between parent body processes (sulphidation) and nebular processes (condensation and precipitation) with RMN compositions. It appears that none of these processes acting in isolation or in tandem can explain the diversity observed in the RMN population. Our interpretation is that the Solar Nebula inherited an initially compositionally diverse population of RMNs from the Giant Molecular Cloud; that a variety of Solar System processes have acted on that population; but none have completely homogenised it. Most RMNs have experienced disk and asteroidal processing, but some may have retained a primordial composition. RMNs have been identified in pre-solar graphite grains (Croat et al., 2013). We anticipate that pre-solar RMNs will be present elsewhere in primitive meteorites.

Titanium diffusion in shinbone of rats with osseointegrated implants.

Dental implants are composed of commercially pure Ti (which is actually an alloy of titanium, and minor or trace components such as aluminium and vanadium). When the implant is inserted, its surface undergoes a number of chemical and mechanical processes, releasing particles of titanium to the medium. The metabolism of free ions of titanium is uncertain; the uptaking processes in the body are not well known, nor their toxic dose. In addition, physical properties of newly formed bone, such as diffusivity and activation energy, are scarce and rarely studied. In this study, we analysed the diffusion of titanium in the titanium-implanted shinbones of six adult male Wistar rats by spatially resolved micro x-ray fluorescence. The measurements were carried out at the microfluorescence station of the x-ray fluorescence (XRF) beamline of the Brazilian synchrotron facility LNLS (from Portuguese 'Laboratorio Nacional de Luz Sincrotron'). For each sample, XRF spectra were taken by linear scanning in area near the new bone formed around the Ti implant. The scanning line shows a clear effect of titanium diffusion whereas calcium intensity presents a different behaviour. Moreover, a clear correlation among the different structures of bones is observed in the Ti and Ca intensities. The results obtained in these measurements may allow determining quantitatively the parameters of diffusion rates and other physical properties of new bone like diffusion coefficients.

Discovering Vanished Paints and Naturally Formed Gold Nanoparticles on 2800 Years Old Phoenician Ivories Using SR-FF-MicroXRF with the Color X-ray Camera

Phoenician ivory objects (8(th) century B.C., Syria) from the collections of the Badisches Landesmuseum, Karlsruhe, Germany, have been studied with full field X-ray fluorescence microimaging, using synchrotron radiation (SR-FF-microXRF). The innovative Color X-ray Camera (CXC), a full-field detection device (SLcam), was used at the X-ray fluorescence beamline of the ANKA synchrotron facility (ANKA-FLUO, KIT, Karlsruhe, Germany) to noninvasively study trace metal distributions at the surface of the archeological ivory objects. The outstanding strength of the imaging technique with the CXC is the capability to record the full XRF spectrum with a spatial resolution of 48 μm on a zone of a size of 11.9 × 12.3 mm(2) (264 × 264 pixels). For each analyzed region, 69696 spectra were simultaneously recorded. The principal elements detected are P, Ca, and Sr, coming from the ivory material itself; Cu, characteristic of pigments; Fe and Pb, representing sediments or pigments; Mn, revealing deposited soil minerals; Ti, indicating restoration processes or correlated with Fe sediment traces; and Au, linked to a former gilding. This provides essential information for the assessment of the original appearance of the ivory carvings. The determined elemental maps specific of possible pigments are superimposed on one another to visualize their respective distributions and reconstruct the original polychromy and gilding. Reliable hypotheses for the reconstruction of the original polychromy of the carved ivories are postulated on this basis.

A microprobe-XRF Beamline on Indus-2 Synchrotron Light Source

A microfocus x-ray fluorescence (XRF) beamline has been setup on Indus-2 synchrotron light source. The beamline works in the x-ray energy range of 4-20 keV. The optics of the beamline comprises of a Si(111) double crystal monochromator for energy tunability and a Kirkpatrick-Baez (KB) based grazing incidence focusing optics. Microprobe XRF scanning over a region of the sample is possible using a 5-axis sample scanning stage. The beamline provides an energy resolution ~ 10−3 -10−4 with a photon flux density of the order of ~ 108 ph/sec./mm2/100mA for the collimated unfocused beam. Measured performance, various attractive features and some initial commissioning results are presented.

A microfocus X-ray fluorescence beamline at Indus-2 synchrotron radiation facility

A microfocus X-ray fluorescence spectroscopy beamline (BL-16) at the Indian synchrotron radiation facility Indus-2 has been constructed with an experimental emphasis on environmental, archaeological, biomedical and material science applications involving heavy metal speciation and their localization. The beamline offers a combination of different analytical probes, e.g. X-ray fluorescence mapping, X-ray microspectroscopy and total-external-reflection fluorescence characterization. The beamline is installed on a bending-magnet source with a working X-ray energy range of 4-20 keV, enabling it to excite K-edges of all elements from S to Nb and L-edges from Ag to U. The optics of the beamline comprises of a double-crystal monochromator with Si(111) symmetric and asymmetric crystals and a pair of Kirkpatrick-Baez focusing mirrors. This paper describes the performance of the beamline and its capabilities with examples of measured results.

Elemental concentration analysis in prostate tissues using total reflection X-ray fluorescence

Prostate cancer (PCa) currently represents the second most prevalent malignant neoplasia in men, representing 21% of all cancer cases. Benign Prostate Hyperplasia (BPH) is an illness prevailing in men above the age of 50, close to 90% after the age of 80. The prostate presents a high zinc concentration, about 10-fold higher than any other body tissue. In this work, samples of human prostate tissues with cancer, BPH and normal tissue were analyzed utilizing total reflection X-ray fluorescence spectroscopy using synchrotron radiation technique (SR-TXRF) to investigate the differences in the elemental concentrations in these tissues. SR-TXRF analyses were performed at the X-ray fluorescence beamline at Brazilian National Synchrotron Light Laboratory (LNLS), in Campinas, São Paulo. It was possible to determine the concentrations of the following elements: P, S, K, Ca, Fe, Cu, Zn and Rb. By using Mann–Whitney U test it was observed that almost all elements presented concentrations with significant differences (α=0.05) between the groups studied.

The first microbeam synchrotron X-ray fluorescence beamline at the Siam Photon Laboratory

The first microbeam synchrotron X-ray fluorescence (µ-SXRF) beamline using continuous synchrotron radiation from Siam Photon Source has been constructed and commissioned as of August 2011. Utilizing an X-ray capillary half-lens allows synchrotron radiation from a 1.4 T bending magnet of the 1.2 GeV electron storage ring to be focused from a few millimeters-sized beam to a micrometer-sized beam. This beamline was originally designed for deep X-ray lithography (DXL) and was one of the first two operational beamlines at this facility. A modification has been carried out to the beamline in order to additionally enable µ-SXRF and synchrotron X-ray powder diffraction (SXPD). Modifications included the installation of a new chamber housing a Si(111) crystal to extract 8 keV synchrotron radiation from the white X-ray beam (for SXPD), a fixed aperture and three gate valves. Two end-stations incorporating optics and detectors for µ-SXRF and SXPD have then been installed immediately upstream of the DXL station, with the three techniques sharing available beam time. The µ-SXRF station utilizes a polycapillary half-lens for X-ray focusing. This optic focuses X-ray white beam from 5 mm × 2 mm (H × V) at the entrance of the lens down to a diameter of 100 µm FWHM measured at a sample position 22 mm (lens focal point) downstream of the lens exit. The end-station also incorporates an XYZ motorized sample holder with 25 mm travel per axis, a 5× ZEISS microscope objective with 5 mm × 5 mm field of view coupled to a CCD camera looking to the sample, and an AMPTEK single-element Si (PIN) solid-state detector for fluorescence detection. A graphic user interface data acquisition program using the LabVIEW platform has also been developed in-house to generate a series of single-column data which are compatible with available XRF data-processing software. Finally, to test the performance of the µ-SXRF beamline, an elemental surface profile has been obtained for a piece of ancient pottery from the Ban Chiang archaeological site, a UNESCO heritage site. It was found that the newly constructed µ-SXRF technique was able to clearly distinguish the distribution of different elements on the specimen.

Elemental changes in hemolymph and urine of Rhodnius prolixus induced by in-vivo exposure to mercury: A study using synchrotron radiation total reflection X-ray fluorescence

In recent years, the effects of pollution on the health of humans and other vertebrates were extensively studied. However, the effects on some invertebrates are comparatively unknown. Recent studies have demonstrated that toxic metals interfere with the reproduction, development and immune defenses of some terrestrial and marine invertebrates. Some environmental conditions including pollution produce chronic and acute effects on different animal's organs and systems. In this work, we investigated changes in the concentrations of Cl, K, Ca, Fe and Zn in Rhodnius prolixus as insect model. The elements were quantified using urine and hemolymph samples collected on different days after feeding the insects with blood containing HgCl2. The synchrotron radiation total reflection X-ray fluorescence measurements were carried at the X-ray fluorescence beamline facility in Brazilian Synchrotron Light Laboratory. The observation reveals that the calcium level was higher in the hemolymph than in urine. On the other hand, the urine collected from insects treated with HgCl2 showed higher level of Cl than hemolymph samples. Ca, Fe and Zn concentrations decrease drastically in urine samples collected after 2days of HgCl2 treatment. The regulation of triatomines excretion was discussed pointing out the importance of trace elements.

Determination of Cu/Zn and Fe in human serum of patients with sickle cell anemia using radiation synchrotron

In this work we analyzed serum samples from patients with Sickle Cell Anemia (SCA) using Total Reflection X-Ray Fluorescence using Synchrotron Radiation (SRTXRF). The SRTXRF measurements were performed at the X-Ray Fluorescence Beamline at the Brazilian National Synchrotron Light Laboratory (LNLS). We studied forty-three patients aged 18–50 suffering from SCA and sixty healthy volunteers aged 18–60. It was possible to determine the concentrations of the following elements: P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb. Moreover, there are evidences of an association among Fe, Cu, Zn and Cu/Zn in the SCA pathogenesis process. The concentrations of Fe and Cu in the serum samples of patients with SCA were larger, 120% and 20%, respectively, when compared with the CG. The serum level Cu/Zn ratio was significantly higher (60%) in the serum samples from patients suffering from SCA than from the CG. Therefore, the Cu/Zn ratio can be used as an adjuvant index in enhancement for diagnosis of SCA.

Energy dispersive X-ray reflectivity applied to the study of thermal stability of self-assembled organic multilayers: Results on phosphonic acids

The temperature evolution of self-assembled phosphonic acid multilayers was investigated by energy dispersive X-ray reflectivity and angular-resolved reflectivity. Energy dispersive measurements were performed in an experimental setup specially designed for the X-ray fluorescence beamline of the Brazilian Synchrotron Light Laboratory. It allows the precise monitoring of phase transitions observed in organic thin film and multilayer systems. The studied multilayers – obtained from dip coating of a solution of octadecylphosphonic acid – present different bilayer periodicities of 50Å (straight bilayer) and 34Å (tilted bilayer). Energy dispersive and angular-resolved data evidence re-organization of the lamellar ordering of octadecylphosphonic acid multilayers as a function of temperature. The energy dispersive technique presents many advantages over conventional methods such as short acquisition time, possibility to vary external parameters and high flux, making it suitable for light scatterers as polymers and other organic molecules.

3D elemental distribution images in biological samples by XRFµCT

An X-ray transmission microtomography (CT) system combined with an X-ray fluorescence microtomography (XRFµCT) system was implemented in the Brazilian Synchrotron Light Laboratory (LNLS), Campinas, Brazil. The aim of this work was to determine the elemental distribution in biological samples (breast, prostate and lung samples) in order to verify the concentration of some elements correlated with characteristics and pathology of each tissue observed by the transmission CT. The experiments were performed at the X-ray fluorescence beamline (D09B-XRF) of the Brazilian Synchrotron Light Laboratory, Campinas, Brazil. A quasi-monochromatic beam produced by a multilayer monochromator was used as an incident beam. The sample was placed on a high-precision goniometer and translation stages that allow rotating as well as translating it perpendicularly to the beam. The fluorescence photons were collected with an energy dispersive HPGe detector placed at 90° to the incident beam, while transmitted photons were detected with a fast Na(Tl) scintillation counter placed behind the sample on the beam path. The CT images were reconstructed using a filtered-back projection algorithm and the XRFµCT images were reconstructed using a filtered-back projection algorithm with absorption corrections. The 3D images were reconstructed using the 3D-DOCTOR software. Results from the 3D visualization showed that the distribution of iron, copper and zinc is different and heterogeneous from the analyzed samples. Copyright © 2011 John Wiley & Sons, Ltd.

3D elemental distribution images by XRFμCT at LNLS—Brazil

An X-ray Transmission Microtomography (CT) system combined with an X-ray Fluorescence Microtomography (XRFμCT) system was implemented in the Brazilian Synchrotron Light Laboratory (LNLS), Campinas, Brazil. The main objective of this work is to determine the elemental distribution in biological samples (breast, prostate and lung samples) in order to verify the concentration of some elements correlated with characteristics and pathology of each tissue observed by the transmission CT. The experiments were performed at the X-Ray Fluorescence beamline (D09B-XRF) of the Brazilian Synchrotron Light Laboratory, Campinas, Brazil. A quasi-monochromatic beam produced by a multilayer monochromator was used as an incident beam. The sample was placed on a high precision goniometer and translation stages that allow its rotation as well as translation perpendicular to the beam. The fluorescence photons were collected with an energy dispersive HPGe detector placed at 90° to the incident beam, while transmitted photons were detected with a fast Na(Tl) scintillation counter placed behind the sample on the beam direction. The CT images were reconstructed using a filtered back-projection algorithm and the XRFμCT were reconstructed using a filtered back-projection algorithm with absorption corrections. The 3D images were reconstructed using the 3D-DOCTOR software.

Avaliação de multielementos em amostras de sangue humano usando SR-TXRF

A técnica de fluorescência de raios X por reflexão total usando radiação síncrotron (SR-TXRF) é uma poderosa ferramenta utilizada para a determinação das concentrações elementares presentes em amostras biológicas. O objetivo deste estudo é avaliar as possíveis alterações causadas por processos de irradiação na concentração de elementos-traço em amostras de sangue humano. As amostras de sangue foram coletadas no Laboratório de Análises Clínicas Dr. Elilel Figueiredo, Rio de Janeiro, e divididas em dois grupos. O primeiro grupo foi irradiado com doses de 1.500, 2.500 e 3.000 cGy, utilizando o irradiador Gammacell 220 Excel, e o segundo foi irradiado com doses que variaram de 2 cGy a 100 cGy, utilizando uma bomba de cobalto Theratron 780 C do Inca, Rio de Janeiro. Todas as amostras de sangue total, plasma e matriz celular foram então liofilizadas e, em seguida, passaram pelo procedimento padrão de digestão. Todas as medidas foram realizadas na linha de fluorescência de raios X do Laboratório Nacional de Luz Síncrotron (LNLS), em Campinas, Brasil. Não se verificou variação significativa na concentração de Ca e, em contrapartida, o K foi o único elemento que sofreu alterações significativas para todas as amostras analisadas em função da dose. A concentração de Fe diminuiu apenas para as amostras de sangue total e plasma. A concentração de Zn apresentou uma diminuição significativa somente para as amostras de sangue total.

Biological tissues analysis by XRF microtomography

The main of this work is to determine the elemental distribution in breast and prostate tissue samples in order to verify the concentration of some elements correlated with characteristics and pathology of each tissue observed by the X-ray transmission microtomography (microCT). The experiments were performed at the X-ray fluorescence beamline of the Brazilian Synchrotron Light Laboratory. The microCT images were reconstructed using a filtered-back-projection algorithm and the XRF microtomographies were reconstructed using a filtered-back-projection algorithm with absorption corrections.

Imaging System for XRF Microtomography at LNLS-Brazil

An X-ray transmission microtomography (CT) system combined with an X-ray fluorescence microtomography (XRFCT) system was implemented in the Brazilian Synchrotron Light Laboratory (LNLS), Campinas, Brazil. The main of this work is to determine the elemental distribution map in reference samples and breast tissue samples in order to verify the concentration of some elements correlated with characteristics and pathology of each tissue observed by the transmission CT. The experiments were performed at the X-Ray Fluorescence beamline (D09B-XRF) of the Brazilian Synchrotron Light Laboratory, Campinas, Brazil. A quasi-monochromatic beam produced by a multilayer monochromator was used as an incident beam. The sample was placed on a high precision goniometer and translation stages that allow rotating as well as translating it perpendicularly to the beam. The fluorescence photons were collected with an energy dispersive HPGe detector placed at 90deg to the incident beam, while transmitted photons were detected with a fast Na(Tl) scintillation counter placed behind the sample on the beam direction. The CT images were reconstructed using a filtered-back projection algorithm and the XRFCT were reconstructed using a filtered-back projection algorithm with absorption corrections.