JGIXA — A software package for the calculation and fitting of grazing incidence X-ray fluorescence and X-ray reflectivity data for the characterization of nanometer-layers and ultra-shallow-implants

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temporary implementation and testing of a confocal sr μxrf system for bone analysis at the x ray fluorescence beamline at elettra

Abstract The confocal μ XRF 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 μ m 2 ) and the size of the confocal volume (confocal mode, 41 × 24 × 34 μ m 2 ) for the Cu–K α 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

Wachstumsminderung

X-ray absorption near edge structure (XANES) analysis in combination with synchrotron radiation induced total reflection X-ray fluorescence (SR-TXRF) acquisition was used to determine the oxidation state of Fe in human cancer cells and simultaneously their elemental composition by applying a simple sample preparation procedure consisting of pipetting the cell suspension onto the quartz reflectors. XANES spectra of several inorganic and organic iron compounds were recorded and compared to that of different cell lines. The XANES spectra of cells, independently from the phase of cell growth and cell type were very similar to that of ferritin, the main Fe store within the cell. The spectra obtained after CoCl2 or NiCl2 treatment, which could mimic a hypoxic state of cells, did not differ noticeably from that of the ferritin standard. After 5-fluorouracil administration, which could also induce an oxidative-stress in cells, the absorption edge position was shifted toward higher energies representing a higher oxidation state of Fe. Intense treatment with antimycin A, which inhibits electron transfer in the respiratory chain, resulted in minor changes in the spectrum, resembling rather the N-donor Fe-,′-dipyridyl complex at the oxidation energy of Fe(III), than ferritin. The incorporation of Co and Ni in the cells was followed by SR-TXRF measurements

Characterization of a submicro-X-ray fluorescence setup on the B16 beamline at Diamond Light Source

An X-ray fluorescence setup has been tested on the B16 beamline at the Diamond Light Source synchrotron with two different excitation energies (12.7 and 17 keV). This setup allows the scanning of thin samples (thicknesses up to several micrometers) with a sub-micrometer resolution (beam size of 500 nm × 600 nm determined with a 50 µm Au wire). Sensitivities and detection limits reaching values of 249 counts s−1 fg−1 and 4 ag in 1000 s, respectively (for As Kα excited with 17 keV), are presented in order to demonstrate the capabilities of this setup. Sample measurements of a human bone and a single cell performed at B16 are presented in order to illustrate the suitability of the setup in biological applications.</jats:p

Implementing light elements detection and quantification in aluminosilicate materials using a Low-Z total-reflection X-ray fluorescence spectrometer

Total-reflection X-ray fluorescence (TXRF) is a well-established atomic spectroscopy technique used for the elemental characterization of different kinds of matrixes in several fields. Previous works demonstrated its applicability for the elemental quantification of aluminosilicates and, in particular, clays. However, one of the limits of the previously developed methods was the detection and quantification of light elements, in particular for those elements with an atomic number (Z) below 13 (Al). In the present work a new TXRF-based analytical method for the quantification of light elements in aluminosilicate materials is described, using an in-house built Low-Z TXRF spectrometer equipped with a Cr source, a multilayer monochromator, an SDD detector equipped with an ultrathin Si3N4 window and a vacuum chamber. Samples were prepared as simple slurries (dispersing 50 mg of powder into 2.5 mL of 1%-Triton X-100 water solution and adding Ag as internal standard) and 10 μL were deposited onto a quartz carrier and dried before the analysis. Light elements such as F, Na and Mg were quantified with a limit of detection of 682, 260 and 133 mg/kg, respectively. Carbon and oxygen could also be detected. The new method allowed a complete analysis of major elements in aluminosilicates from F to Fe. The method showed a good accuracy in the range of 80–120% and the results agreed with the data obtained with a commercial TXRF spectrometer (for elements &gt;13) and WDXRF, employed as reference methods. Despite a lower precision in respect to WDXRF, in some samples the quantification of F was possible only by using the Low-Z TXRF spectrometer. Finally, the method demonstrated to be suitable for the analysis of aluminosilicates, in particular when low amounts of sample (few milligrams) are available