Total X-ray Fluorescence Spectrometry Research Articles

Effect of primary copper metabolism disturbance on elemental, protein, and lipid composition of the organs in Jackson toxic milk mouse.

Toxic milk (txJ) is an autosomal recessive mutation in the Atp7b gene in the C3H/HeJ strain, observed at The Jackson Laboratory in Maine, USA. TxJ mice exhibit symptoms similar to those of human Wilson's disease (WD). The study aimed to verify organ involvement in a mouse model of WD. TxJ mice and control animals were sacrificed at 2, 4, 8, and 14months of age. Total X-ray Fluorescence Spectroscopy (TXRF) was used to determine the elemental concentration in organs. Tissue chemical composition was measured by Fourier Transform Infrared Spectroscopy (FTIR). Additionally, hybrid mapping of FTIR and microXRF was performed. Elevated concentrations of Cu were observed in the liver, striatum, eye, heart, and duodenum of txJ mice across age groups. In the striatum of the oldest txJ mice, there was lower lipid content and a higher fraction of saturated fats. The secondary structure of striatum proteins was disturbed in txJ mice. In the livers of txJ mice, higher concentrations of saturated fats and disturbances in the secondary structure of proteins were observed. The concentration of neurofilaments was significantly higher in txJ serum. The distribution of Cu deposits in brains was uniform with no prevalence in any anatomic structure in either group, but significant protein structure changes were observed exclusively in the striatum of txJ. In this txJ animal model of WD, pathologic copper accumulation occurs in the duodenum, heart, and eye tissues. Increased copper concentration in the liver and brain results in increased saturated fat content and disturbances in secondary protein structure, leading to hepatic injury and neurodegeneration.

Determination of germanium and other trace elements concentration in mineral waters of Low Beskid (Poland) used for crenotherapy

Crenotherapy is a natural treatment and health protection method, thus using natural mineral water are gaining popularity as an alternative to pharmacotherapy or as additional support in many types of diseases. The aim of this study was to determine the occurrence of germanium (Ge) in mineral non-geothermal waters from Low Beskid area, Poland. The collected mineral water samples from natural springs and wells were analyzed using total X-ray fluorescence spectroscopy (TXRF). In total, 25 mineral water samples and 4 commercially available mineral waters (PET and glass bottled) used in crenotherapy were analyzed to determine the levels of Ge and 11 other indicators (total dissolved solids (TDS), pH, Br, As, Fe, Mn, Zn, Cu, Sr, Ba and Cl/Br index). Moreover, relations between: Ge concentration and total mineralization and Br concentrations, likewise assessments of Ge origin and on the potential impact of Ge in mineral water on human health, were performed. The results demonstrated that in 22 out of 25 samples Ge was detected, in the range from 0.99 μg/l to 123.83 μg/l. The results indicate that the relic waters, which remain in contact with deposits of sediments containing high quantities of organic compounds indicate the highest Ge concentration collected in Wysowa-Zdroj. The findings of the current work conclude that the quantity of germanium consumed with the analysed curative non-geothermal waters form Low Beskid taken directly at the source has no negative impact on human health.

Electrical properties of proton-conducting BaCe0.8Y0.2O3-δ and the effects of bromine addition

A detailed analysis of the electrical properties of the proton-conducting BaCe0.8Y0.2O3-δ phase (BCY20) and the effects of Br doping has been undertaken. Members of the system of nominal stoichiometry BaCe0.8Y0.2O2.9-(x/2)±δBrx (x = 0, 0.05, 0.1 and 0.2) were synthesised by a citrate-nitrate process and high-temperature annealing up to 1500 °C. X-ray diffraction revealed the formation of single-phase material with a monoclinically distorted perovskite structure (space group I2/m) with greater distortion for Br-synthesised phase. Significant contrasts in electrical behaviour and stability between BCY20 and Br-synthesised series members were also found. However, chemical analysis by total X-ray fluorescence spectroscopy indicated that only trace amounts of Br remain after synthesis, indicating that Br addition influences stoichiometry but not directly the physicochemical properties. Higher conductivity is observed for the Br-synthesised compositions in wet and dry oxidising conditions in the temperature range 300–900 °C, reaching a value of 5.8 S m−1 at 800 °C for the x = 0.2 member in wet O2 (pH2O ∼ 0.022 atm). Determination of partial-conductivity components indicated that, in humid conditions and low temperature, the conductivity of 20% Br-synthesised material is principally protonic (tH = 0.91 at 600 °C and pO2 = 0.2 atm) and superior to that of BCY20. Mixed oxide-ionic-electronic conductivity dominates at high pO2 (1 atm) and oxide-ionic conductivity at low pO2 (∼10−4 atm) in the temperature range 600–900 °C for both BCY and Br-doped samples. Stability was found to be poorer in CO2 for the Br-synthesised phases as determined by thermogravimetry and prolonged conductivity measurements.

An Alternative and Simple Method for the Preparation of Bare Silica Nanoparticles Using Sugarcane Waste Ash, an Abundant and Despised Residue in the Brazilian Industry

Sugarcane waste ash, a Si-rich waste product, is generated in large quantities and creates a serious disposal problem in the Brazilian ethanol-sugar industry, affecting the environment and public health. Here, a simple method capable of generating bare silica nanoparticles utilizing this residue is demonstrated. Firstly, the crystalline silica present in sugarcane waste ash (SWA) was converted into amorphous by melting a mixture of sodium hydroxide and SWA at 550 oC for 1 h. The silica nanoparticles (SiO2NPs) were formed by lowing pH. This production process of SiO2NPs from SWA was optimized varying the ash:NaOH mass ratio, increasing the silica extraction up to 96%. The sample’s composition was characterized by total X-ray fluorescence spectroscopy, morphology and physical-chemical properties were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction, specific surface area measurements, Fourier-transform infrared spectroscopy (FTIR) and thermogravimetric analyses (TGA), followed by use as adsorbent for the removal of methylene blue dye. With this process of extraction, nanoparticles smaller than 100 nm were generated, with a surface area of 63 m2 g-1 and a maximum adsorption capacity of 37 mg g-1 for methylene blue. The results indicate a successful process for obtaining an adsorbent from an industrial waste product using a cost effective and rapid synthesis procedure rendering renewable product.

Monitoring of elements in mosses by instrumental neutron activation analysis and total X-ray fluorescence spectrometry

This research presents a study of environmental monitoring at different sampling sites from the Metropolitan Area of the Valley of Toluca (MAVT) Mexico by means of moss samples. The selected sampling sites included urban, transitional and natural protected areas. The mosses were obtained in two campaigns within two periods of the year: rainy-season and dry-cold-season. During the sampling, seven species of moss were identified, among them: Leskea angustata (Tayl.) and Fabronia ciliaris (Brid.) were the most abundant. One sample of each species was analyzed by SEM in order to determine their morphology. After that, the samples were analyzed by instrumental neutron activation analysis (INAA) and total X-ray fluorescence spectrometry (TXRFS) in order to determine the metals concentration. The results indicate that the Urban Region was significantly impacted by pollution compared to the natural protected Areas. The cluster statistical analysis results indicated that the sampling sites with the highest concentration of metals are located in the urban areas. Enrichment factors show that As, Cr, Cu, Zn, Pb, Se, Cs, and Sb are highly enriched mainly by anthropogenic sources.

Quantification of total element concentrations in soils using total X-ray fluorescence spectroscopy (TXRF)

Total X-ray fluorescence spectroscopy (TXRF) determines concentrations of major and trace elements in multiple media. We developed and tested a method for the use of TXRF for direct quantification of total element concentrations in soils using an S2 PICOFOX™ spectrometer (Bruker AXS Microanalysis GmbH, Germany). We selected 15 contrasting soil samples from across sub-Saharan Africa for element analysis to calibrate the instrument against concentrations determined using the inductively coupled plasma-mass spectroscopy (ICP-MS) standard method. A consistent underestimation of element concentrations using TXRF compared to ICP-MS reference analysis occurred, indicating that spectrometer recalibration was required. Single-element recalibration improved the TXRF spectrometer's sensitivity curve. Subsequent analysis revealed that TXRF determined total element concentrations of Al, K, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, and Ga accurately (model efficacy/slope close to 1:1 line, and R2>0.80) over a wide range of soil samples. Other elements that could be estimated with an acceptable precision (R2>0.60) compared with ICP-MS although generally somewhat under- or overestimated were P, Ca, As, Rb, Sr, Y, Pr, Ta and Pb. Even after recalibration, compared to ICP-MS the TXRF spectrometer produced underestimations for elements Na, Mg, Ba, Ce, Hf, La, Nd, W and Sm and overestimations for elements Bi, Tl and Zr. We validated the degree of accuracy of the TXRF analytical method after recalibration using an independent set of 20 soil samples. We also tested the accuracy of the analysis using 2 multi-element standards as well as the method repeatability on replicate samples. The resulting total element concentration repeatability for all elements analyzed were within 10% coefficient of variability after the instrument recalibration except for Cd and Tl. Our findings demonstrate that TXRF could be used as a rapid screening tool for total element concentrations in soils assuming that sufficient calibration measures are followed.

Surface treatment for the atomic layer deposition of HfO2 on silicon

The atomic layer deposition (ALD) of HfO2 on silicon with a Cl2 surface treatment is investigated by physicochemical and electrical techniques. The specificity of this treatment is to create, on a HF-dipped silicon surface, the nucleation sites necessary for the ALD growth. The growth rates obtained by spectroscopic ellipsometry and total x-ray fluorescence spectroscopy indicate that the nucleation sites (i.e., the –OH groups), which are necessary to perform some bidimensional ALD growth, are generated during this surface treatment. After deposition of thin HfO2 layers (from a few monolayers up to 8.7nm), a very thin parasitic SiOx layer, underneath 1 monolayer of Hf silicate, is observed by x-ray photoelectron spectroscopy. Nevertheless, an equivalent oxide thickness of 1.1nm is obtained with an as-deposited 3.7nm thick HfO2 layer.