Synchrotron Radiation Excited X-ray Fluorescence Research Articles

Determination of main rock-forming elements, strontium and zirconium by X-ray fl uorescence analysis for the geochemical characterization of bottom sediments

Quantitative X-ray fluorescence determination of major rock-forming oxides (Na 2 O, MgO, Al 2 O 3 , SiO 2 , P 2 O 5 , K 2 O, CaO, TiO 2 , MnO and Fe 2 O 3 ) and some microelements (Sr and Zr) was performed in the samples of 143 cm-long sediment core of Lake Baunt (Buryat Republic) by the wavelength-dispersive X-ray fluorescence analysis on the S8 Tiger spectrometer. Calibration curves were obtained by measuring the certified reference materials of the sedimentary rocks. Both analyzed and reference samples were prepared as glass beads by fusion of 110 mg of sample with1.1 g of lithium metaborate. We have used 110 mg mass to ensure the formation of beads with appropriate 10 to 12 mm size across to be measured by the spectrometer with8 mm mask. Rh Kα Compton line was used as a background standard for Sr and Zr determination. The repeatability did not exceed the allowable standard deviation for a wide range of concentrations. Results of major rock-forming oxides determination were compared with the data of spectrophotometry and flame photometry techniques, results of Sr and Zr determination were compared with the data of synchrotron radiation excited X-ray fluorescence technique. All results of the X-ray fluorescence analysis were accepted as satisfactory. Quantitative analysis of each centimeter of Lake Baunt sediment core allowed building first reconstructions of the local environment during the last 7000 years with unique resolution of about 100 years. Keywords: wavelength-dispersive X-ray fluorescence analysis, synchrotron radiation induced X-ray fluorescence analysis, sediments, paleoclimate (Russian) DOI: http://dx.doi.org/10.15826/analitika.2017.21.1.003 A.A. Amosova, V.M. Chubarov,E.V. Kaneva, Iu.N. Markova Vinogradov Institute of Geochemistry, Siberian Branch of Russian Academy of Sciences, ul. Favorsky , 1A, Irkutsk , 664033, Russian Federation

Scanning protein analysis of electrofocusing gels using X-ray fluorescence

Recently, "metallomics," in addition to genomics and proteomics, has become a focus as a novel approach to identify sensitive fluctuations in homeostasis that accompany metabolic processes, such as stress responses, differentiation, and proliferation. Cellular elements and associated protein behavior provide important clues for understanding cellular and disease mechanism(s). It is important to develop a system for measuring the native status of the protein. In this study, we developed an original freeze-dried electrofocusing native gel over polyimide film (native-gel film) for scanning protein analysis using synchrotron radiation excited X-ray fluorescence (SPAX). To our knowledge, this is the first report detailing the successful mapping of metal-associated proteins of electrofocusing gels using X-ray fluorescence. SPAX can provide detection sensitivity equivalent to that of LA-ICP-MS. In addition to this increased sensitivity, SPAX has the potential to be combined with other X-ray spectroscopies. Our system is useful for further applications in proteomics investigating cellular element-associated protein behaviors and disease mechanisms.

Macro–micro elementary content of liver and lungs in rats with alimentary adiposity (SRXRF)

AbstractIn alimentary adiposity, some microelements take active part in the metabolism change that proves to be true by an essential deviation from the norm of their concentration in liver and lung tissues during the physiological hunger and soon after fat consumption. The concentrations (in µg/g) of the following chemical elements P, S, Cl, K, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, and Sr were determined by synchrotron radiation excited X‐ray fluorescence (SRXRF) analysis. The measurements were carried out at the experimental station of X‐ray fluorescence elemental analysis (Budker Institute of Nuclear Physics SB RAS, storage ring VEPP‐3). In alimentary adiposity, deficiency of separate microelements does not concern all organisms, but only some organs. At the condition of physiological hunger in the liver and lungs of rats with alimentary adiposity, the concentrations of As and Br are decreased; besides, in lungs the concentrations of Zn, Se, and Rb are also lowered. Copyright © 2009 John Wiley & Sons, Ltd.

Analysis of trace Co in synthetic diamonds using synchrotron radiation excited X-ray fluorescence analysis

Synchrotron radiation excited X-ray fluorescence analysis was utilized for characterization of trace impurities in synthetic diamonds. Advantage of the energy tunability was fully utilized to evaluate the attenuation of X-rays through the sample, and the absorption corrected X-ray fluorescence yield was utilized for quantitative analysis. Diamonds grown with several types of metallic solvents were investigated, and quantitative analysis of trace Co was carried out. It was found that Co prefers to be dissolved into {1 1 1} growth sector and that Co concentration in the {1 1 1} growth sector decreases one order of magnitude with the existence of Ni in the solvent. XANES spectra of dissolved Co shows characteristic pre-edge feature similar to that reported with the dissolved Ni. Experimental results suggest that both Ni and Co occupy in the similar site in the diamond lattice and that Ni is easier to be dissolved into diamonds.

Intramyocardial vascular volume distribution studied by synchrotron radiation-excited X-ray fluorescence.

We evaluated the vascular volume distribution with fine resolution (0.1-1.3 mg myocardial tissue) in the sagittal plane of the left ventricle by using the microsphere filling method in 21 dogs. The coronary arterial volume density in the sagittal plane did not exhibit normal distribution and was characterized by variability among the outer-to-inner layers and within the layers (+2SD/-2SD > 80 times), and the median values in the layers ranged from 4.7 to 22. 9 nl/mg myocardial tissue. The fractal analysis of vascular volume revealed a self-similar nature with a fractal dimension (D value) similar to that of flow distribution (1.20 +/- 0.05 and 1.24 +/- 0. 09 for vascular volume and flow distribution, respectively) and had a more marked variability than the flow. The correlation of the regional vascular volume between adjacent regions decreased as the distance increased. However, the correlation coefficients in the endocardial-to-epicardial direction were significantly higher than those in the anterior-to-posterior direction (P < 0.05 by paired t-test). In conclusion, we determined intramyocardial vascular volume density in the sagittal plane, and the distribution revealed considerable variability, self-similarity, and asymmetry in the correlation among the adjacent regions. These observations could be related to the characteristics of the intramural coronary vascular network.

Site-specific lead distribution in scales of lead-administered carp ( Cyprinus carpio) by non-destructive SR-XRF analysis

By utilizing non-destructive synchrotron radiation-excited X-ray fluorescence (SR-XRF), we observed the distribution of lead (Pb) in both ontogenic and regenerating scales of lead-administrated carp, Cyprinus carpio. The fish in the Pb-administered group were fed pellets containing 1 mg/g of Pb at a rate of 1.5% body weight per day for 30 days. In the ontogenic scales, Pb was highly accumulated near the basal edge of the scale and the accumulated amount decreased toward the focus of the scale. On the other hand, in the regenerating scales, high accumulation was observed near the basal edge and the accumulated amount remained high toward the focus. The present results of Pb accumulation correspond well with the region which is calcifying in the ontogenic and regenerating scales, and indicate that the distributions of Pb show when and how long Pb was administered.

Changes in the Distributions of Chemical Elements in Regenerating Scales of Carp, Cyprinus carpio, Studied by SRXRF Imaging

Two-dimensional distributions of calcium, phosphorus, strontium, and zinc in regenerating scales of carp, Cyprinus carpio, were observed over a period of 90 days by utilizing synchrotron radiation-excited X-ray fluorescence (SRXRF) imaging. On the 15th day, these elements were highly accumulated in the part that is exposed to the ambient water, and the accumulated amount decreased linearly toward the basal edge through the focal area of the scale. As the regeneration progressed, this characteristic pattern changed such that the amount of each element in the rim part, which was exposed to the ambient water, obviously increased, while the amount in the basal edge decreased. However, the relative amounts of phosphorus, strontium, and zinc with respect to calcium in the regenerating scale remained almost constant during the regeneration. In addition, it was found that the diameter of, and the number of ridges in, the regenerating scales increased rapidly during the first 15 days, and increased at a slower pace later on.

Local Continuity of Myocardial Blood Flow Studied by Monochromatic Synchrotron Radiation–Excited X-ray Fluorescence Spectrometry

We have developed a monochromatic synchrotron radiation-excited system for two-dimensional mapping of x-ray fluorescence evoked from heavy element-loaded microspheres, which can evaluate myocardial blood flow in small contiguous regions with a small methodological error: 10.8 +/- 2.4% of the average of difference of the dual flow for 7- to 10-mg myocardial tissue (4 dogs). The fractal D value obtained from the slope of the log relative dispersion-log mass plot was 1.21 +/- 0.08 for a voxel size of 7 to 1260 mg (5 dogs) and that for a voxel size of 2.5 to 40 mg (1.12 +/- 0.06) was smaller than that for a voxel size of 40 to 1280 mg (1.25 +/- 0.14, P < .05, ANOVA, 4 dogs). The distance-correlation coefficient relation for paired myocardial regions was attenuated (correlation analysis), and the correlation coefficients between the original grouping and the two aggregates of the adjacent regions were dissociated (extended correlation analysis) under reduction of coronary perfusion pressure (6 dogs). Suppression of myocardial contraction with lidocaine (3 dogs) and vasodilation with adenosine partly improved the distance-correlation coefficient relation under reduced coronary perfusion pressure. Thus, an x-ray fluorescence system designed for precise flow measurement shows that the fractal nature of local flow distribution can be extended into regions smaller than previously reported, that in these regions the flow becomes more homogeneous, and that the self similarity and continuity of local flow are attenuated by the reduction of coronary perfusion pressure and improved by contractile suppression and coronary vasodilation.

X-ray fluorescence analysis using synchrotron radiation

The use of synchrotron radiation has recently gained considerable attention as an excitation source for X-ray fluorescence analysis. This article covers the current advantages and limitations of materials analysis by synchrotron radiation excited X-ray fluorescence, centering around the experimental cases of the author and his colleagues.

Imaging multielement analysis with synchrotron radiation excited X-ray fluorescence radiation

Using synchrotron radiation for excitation in energy dispersive X-ray fluorescence analysis, very low limits of detection are achievable and imaging analysis with high spatial resolution is possible. In order to attain a resolution below 10 μm, slit apertures were employed to scan the sample, improving the signal-to-noise ratio considerably. The measured data were transformed using filtered backprojection, thus obtaining the decoded images. Spatial resolutions down to 3 μm were successfully obtained.

Characterization of Co–O Thin Films by X-Ray Fluorescence Using Chemical Shifts of Absorption Edges

The chemical shift of K absorption edges of cobalt oxides were measured by synchrotron radiation excited X-ray fluorescence technique using an energy dispersive detection system. A thin film of less than 100 angstroms can be easily characterized because of the significantly high sensitivity of the present method. The oxidation process of magnetic thin films of Co–O is quantitatively analyzed.

Synchrotron radiation excited x-ray fluorescence analysis using total reflection of x-rays

La limite de detection minimum obtenue avec une excitation monochromatique est inferieure a 1 ppb ou 1 pg

Synchrotron radiation excited X-ray fluorescence analysis using wide band pass monochromators

Wide band pass X-ray monochromators using reflection/transmission mirror and reflection mirror/absorber combinations were applied to the synchrotron radiation excited energy dispersive X-ray fluorescence analysis. Transmission mirrors were made from soap films or thin mylar films and were used as high pass filters. Characteristics of both films are described in detail. The width of band pass thus obtained was wider than 20%. Minimum detection limits in relative concentration and absolute amount are of the order of 0.1 ppm and less than 0.1 pg, respectively, when there is no line interference.

SRによる蛍光X線分析の可能性

X-ray fluorescence trace and micro analyses using a synchrotron radiation source are of value in both research and technology. The outstanding properties of SR which serve to enhance the capability of X-ray spectrochemical analysis are the tunability of the energy spectrum, high brightness, and polarization for reduced scattered background. The state of arts and the future capability of this synchrotron radiation excited X-ray fluorescence analysis are presented. Applications of this method to earth science and materials science are also discussed.