Synchrotron Radiation X-ray Fluorescence Research Articles

Enhancement of mineral density and mechanical properties in root caries treated with silver diammine fluoride and glass ionomer cement, with emphasis on silver ion distribution

ObjectivesThis study aimed to measure the distribution of silver ion (Ag+), mineral recovery, and nanohardness in carious lesions and comprehensively evaluate the degree of dentin restoration. MethodsSixty human teeth with root caries were randomly assigned to the control, silver diammine fluoride (SDF) [Safo], and SDF+Glass ionomer cement (GIC) treatment [Safo+Fuji] groups. Micro-computed tomography (CT) was performed at five time points for each sample before/after treatment to evaluate mineral density within and around carious lesions. Three months following treatment, 12 samples were selected for synchrotron radiation X-ray fluorescence analysis to evaluate Ag+ distribution, while 15 samples were selected for nanoindentation. Data were analyzed using Dunnett's T3 test for micro-CT and Wilcoxon rank sum test with Bonferroni correction (p = 0.017) for nanoindentation. The correlation between hardness and mineral change was analyzed using the Spearman rank correlation coefficient. ResultsThe Safo and Safo+Fuji groups showed significantly higher mineral recovery rates than did the control group (p<0.001). In the Safo group, Ag+ accumulated in the deeper layers rather than the superficial layer of caries. In the Safo+Fuji group, Ag+ was found evenly distributed throughout caries, with only a few Ag+ detected in the GIC layer. Hardness in the Safo+Fuji group was significantly higher compared with the Safo group at depths in the range of 10–50 µm. ConclusionIn the presence of GICs, SDF exhibited high remineralization capacity when diffusing throughout carious lesions over time. Combined treatment with SDF and GIC could strengthen root dentin even in the presence of caries. Clinical significanceWe found that combination treatment with SDF and GIC could increase mineral density in caries and improve the hardness of the tooth structure compared with fluoride-based agents alone. These findings might pave the way for future clinical trials to determine the therapeutic potential of nanotechnology-based restorative materials.

High-energy SR-XRF Imaging of Cesium and Trace Elements in Mouse Kidneys: Short Communication.

For understanding trace element dynamics in tissues, methods for analyzing elemental distribution and localization without destroying tissue structures and cell arrangements are desired. Synchrotron radiation X-ray fluorescence (SR-XRF) analysis is one of the non-destructive and multi-element simultaneous analyses. The kidney is the major excretion pathway of cesium (Cs) taken into the body, and an understanding of cesium distribution in the kidney would be useful for establishing technology to facilitate the excretion of radioactive Cs from the body due to nuclear disasters. In the present study, the distribution of cesium and trace elements, such as iron (Fe) and zinc (Zn), corresponding to the kidney structure was examined in Cs-administered mice by SR-XRF imaging with high-energy excitation X-rays (40keV). By beam scanning with a 200-µm square beam, clear Cs images corresponding to the renal layer structure were obtained for the renal specimen at the early phase after Cs administration with the mean renal Cs concentration of 24.1 ± 3.2μg/g. Cs was distributed mainly in the medulla and the outer stripe of the outer medulla located in the center area of the kidney. Unlike the Cs distribution, endogenous Fe and Zn tended to be lower in the medulla than in the outer stripe of the outer medulla and the cortex. This method is effective for analyzing Cs distribution because it can simultaneously analyze the distribution of endogenous trace elements.

Comprehensive study of nanostructured Bi2Te3 thermoelectric materials - insights from synchrotron radiation XRD, XAFS, and XRF techniques.

In this contribution, a comprehensive study of nanostructured Bi2Te3 (BT) thermoelectric material was performed using a combination of synchrotron radiation-based techniques such as XAFS, and XRF, along with some other laboratory techniques such as XRD, XPS, FESEM, and HRTEM. This study aims to track the change in morphological, compositional, average and local/electronic structures of Bi2Te3 of two different phases; nanostructure (thin film) and nanopowders (NPs). Bi2Te3 nanomaterial was fabricated as pellets using zone melting process in a one step process, while Bi2Te3 thin film was deposited on sodalime glass substrate using a vacuum thermal evaporation technique. Synchrotron radiation-based Bi LIII-edge fluorescence-mode X-ray absorption fine structure (XAFS) technique was performed to probe locally the electronic and fine structures of BT thin film around the Bi atom, while transmission-mode XAFS was used for BT NPs distributed in the PVP matrix. The structural features of the collected Bi LIII XANES spectra of thin film and powder samples of BT are compared with the simulated XANES spectrum of BT calculated using FDMNES code at 5 Å cluster size. Combining different off-line structural characterization techniques (XRD, FESEM, XPS, and HRTEM), along with those of synchrotron radiation-based techniques (XAFS and XRF) is necessary for complementary and supported average crystal, chemical, morphological and local electronic structural analyses for unveiling the variation between Bi2Te3 in the nanostructure/thin film and nanopowder morphology, and then connecting between the structural features and functions of BT in two different morphologies. After that, we measured the Seebeck coefficient and the power factor values for both the BT nanopowder and thin film.

Cobalt and Chromium Ions Impair Macrophage Response to Staphylococcus aureus Infection.

Cobalt-chromium-molybdenum (CoCrMo) alloys are routinely used in arthroplasty. CoCrMo wear particles and ions derived from arthroplasty implants lead to macrophage-driven adverse local tissue reactions, which have been linked to an increased risk of periprosthetic joint infection after revision arthroplasty. While metal-induced cytotoxicity is well characterized in human macrophages, direct effects on their functionality have remained elusive. Synchrotron radiation X-ray microtomography and X-ray fluorescence mapping indicated that peri-implant tissues harvested during aseptic revision of different arthroplasty implants are exposed to Co and Cr in situ. Confocal laser scanning microscopy revealed that macrophage influx is predominant in patient tissue. While in vitro exposure to Cr3+ had only minor effects on monocytes/macrophage phenotype, pathologic concentrations of Co2+ significantly impaired both, monocyte/macrophage phenotype and functionality. High concentrations of Co2+ led to a shift in macrophage subsets and loss of surface markers, including CD14 and CD16. Both Co2+ and Cr3+ impaired macrophage responses to Staphylococcus aureus infection, and particularly, Co2+-exposed macrophages showed decreased phagocytic activity. These findings demonstrate the immunosuppressive effects of locally elevated metal ions on the innate immune response and support further investigations, including studies exploring whether Co2+ and Cr3+ or CoCrMo alloys per se expose the patients to a higher risk of infections post-revision arthroplasty.

Screening the phytotoxicity of micro/nanoplastics through non-targeted metallomics with synchrotron radiation X-ray fluorescence and deep learning: Taking micro/nano polyethylene terephthalate as an example

Microplastics (MPs) and nanoplastics (NPs) are global pollutants with emerging concerns. Methods to predict and screen their toxicity are crucial. Elemental dyshomeostasis can be used to assess toxicity of environmental pollutants. Non-targeted metallomics, combining synchrotron radiation X-ray fluorescence (SRXRF) and machine learning, has successfully differentiated cancer patients from healthy individuals. The whole idea of this work is to screen the phytotoxicity of nano polyethylene terephthalate (nPET) and micro polyethylene terephthalate (mPET) through non-targeted metallomics with SRXRF and deep learning algorithms. Firstly, Seed germination, seedling growth, photosynthetic changes, and antioxidant activity were used to evaluate the toxicity of mPET and nPET. It was showed that nPET, at 10 mg/L, was more toxic to rice seedlings, inhibiting growth and impairing chlorophyll content, MDA content, and SOD activity compared to mPET. Then, rice seedling leaves exposed to nPET or mPET was examined with SRXRF, and the SRXRF data was differentiated with deep learning algorithms. It was showed that the one-dimensional convolutional neural network (1D-CNN) model achieved 98.99% accuracy without data preprocessing in screening mPET and nPET exposure. In all, non-targeted metallomics with SRXRF and 1D-CNN can effectively screen the exposure and phytotoxicity of nPET/mPET and potentially other emerging pollutants. Further research is needed to assess the phytotoxicity of different types of MPs/NPs using non-targeted metallomics.

A comparative evaluation of enrichment of trace elements in South African and Australian coals using SRXRF

In this study, coals imported from South Africa and Australia were characterized and quantified by an accelerator based X-ray emission technique viz., Synchrotron Radiation X-ray Fluorescence (SRXRF). Twelve trace metallic analytes (V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Rb, Sr, and Pb) and four minor elements (K, Ca, Ti, and Fe) were quantified by SRXRF. Elements of environmental concern, V, Cr, Co, Sr, and Pb were found to be enriched with respect to Clarke's world coal values. Correlation analysis reveals that most of the enriched trace elements in both the studied coals have organic affinity rather than inorganic affinity except Cr. Elements were clustered into three groups by hierarchical cluster analysis based on their chemical affinities.

Effect of Coconut Fiber Biochar and Its Nitrate Modification on Pb Passivation in Paddy Soils

The effects of coconut fiber biochar (CFB) and nitrate-modified coconut fiber biochar (NCFB) on the passivation of exogenous lead (Pb) in paddy soils and their underlying mechanisms were investigated using soil incubation experiments combined with spectroscopic techniques such as scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), synchrotron radiation X-ray fluorescence (SRXRF), and Fourier transform infrared absorption spectroscopy (FTIR). The effects of NCFB and CFB on the passivation of exogenous lead (Pb) in paddy soils and its underlying mechanisms were investigated. Compared with that of CFB, the inner wall of NCFB honeycomb pores was rougher, and the amount of alcohol-phenol-ether functional groups containing the C-O structure and the amount of carboxyl groups containing the C[FY=,1]O/O[FY=,1]C-O structure on the surface of CFB was significantly decreased after nitric acid modification. Compared with that in the control (without biochar) paddy soil after 150 d of incubation, the EDTA-extracted Pb content in the paddy soil with CFB and NCFB was reduced by 39.7% and 105.4%, respectively. The carbonate-bound and Fe-Mn oxide-bound Pb contents were significantly lower, and the organic-bound and residue Pb contents were significantly higher in the NCFB-added soil. The SRXRF scans showed that the exogenous Pb was enriched in the microregions of CFB particles rich in Ca and Cu elements and relatively less so in the microregions of soil aggregates rich in the Fe, Mn, and Ti elements. In addition, the characteristic peaks of carboxylates (1384 cm-1) in A-CFBPb and A-NCFBPb were significantly enhanced in the incubation experiment in the presence of exogenous Pb compared to A-CFB and A-NCFB in the absence of exogenous Pb. The addition of CFB or NCFB was more effective in passivating exogenous Pb in paddy soils and promoted the gradual transformation of Pb from unstable to more stable forms in paddy soils to achieve the effect of passivating Pb. The greater amount of carboxyl functional groups in NCFB participated in the passivation of exogenous Pb, which made NCFB more effective than CFB in passivating Pb. NCFB was more effective than CFB in passivating exogenous Pb in paddy soils due to its rougher inner walls of honeycomb pores and abundant carboxyl functional groups. In tropical areas such as Hainan, coconut fiber biochar and its modification can be considered as an environmentally friendly candidate method for the remediation of soil Pb contamination.

Radiation makes cells select the form of death dependent on external or internal exposure: apoptosis or pyroptosis

Internal radiation exposure from neutron-induced radioisotopes environmentally activated following atomic bombing or nuclear accidents should be considered for a complete picture of pathologic effects on survivors. Acute and localized high dose radiation exposure from hot particles taken into the body must induce cell death and severe damage to tissues, whether they are proliferating or not. However, very little the cellular and molecular mechanisms underlying this internal radiation pathology has been investigated. Male Wistar rats were internally exposed to 56MnO2 powder by inhalation. Small intestine samples were investigated by histological staining at acute phase (6 h, 3 days and 14 days) and late phase (2, 6 and 8 months) after the exposure. Histological location and chemical properties of the hot particles embedded in small intestinal tissues were analyzed by synchrotron radiation—X-ray fluorescence—X-ray absorption near-edge structure (SR–XRF–XANES). Hot particles located in the intestinal cavity were identified as accumulations of Mn and iron. Pathological changes showed evidence of crypt shortening, massive cell death at the position of stem cell zone, including apoptosis and pyroptosis from 6 h through 8 months in the internal exposed rats.

Elemental profiles in distant tissues during tumor progression

BackgroundEssential elements have functions in tumor progression by promoting protumoral cellular processes, such as proliferation, and migration, among others. Obtaining an understanding of how these elements relate to tumor progression processes is of great importance for research. Elemental profile studies in distant tissues, which can be modulated by tumor cells to promote metastasis, have not been sufficiently investigated. The main goal of this study is to evaluate multielemental distribution during tumor progression, focusing on tumor tissue and distant tissues that may be affected.MethodsTumor progression in vivo was simulated by inoculating C57BL/6 mice with Lewis Lung Carcinoma (LLC) cells. Samples of the primary tumor and distant tissues were collected during 5 weeks of tumor progression for the control and experimental (tumor-bearing) groups. The biological samples were analyzed using the synchrotron radiation X-Ray fluorescence technique. Data on the concentration of P, S, K, Ca, Mn, Fe, Cu, and Zn in the samples were obtained and statistically analyzed to evaluate the distribution of the elements during tumor progression in the primary tumor as well as distant tissues.ResultsIt was possible to observe significant changes in the concentrations’ distribution of P, S, K, Ca, Mn, Fe, and Cu in distant tissues caused by the presence of tumor cells. It was also possible to detect a greater similarity between tumor tissue (which has the lung as tissue of origin) and a tissue of non-origin, such as the liver, which is an unprecedented result. Moreover, changes in the distributions of concentrations were detected and studied over time for the different tissues analyzed, such as primary tumor, liver and lung, in Control and Tumor groups.ConclusionsAmong other results, this paper could explore the modulation of distant tissues caused by the presence of a primary tumor. This could be achieved by the evaluation of several elements of known biological importance allowing the study of different biological processes involved in cancer. The role of essential elements as modulators of the tumor microenvironment is a relevant aspect of tumor progression and this work is a contribution to the field of tumoral metallomics.

Microthermometry and Synchrotron Radiation X‐ray Fluorescence Analysis of Fluid Inclusions in the Dongping Gold Deposit, Northern Margin of the North China Craton

AbstractTo shed light on the genesis of the Dongping deposit and reveal the behaviour of CO2, Au and other ore elements (e.g., Cu, Fe, Zn, As, Sb, Co etc.) in ore‐forming fluids, petrographic, microthermometric and synchrotron radiation X‐ray fluorescence (SRXRF) analyses of fluid inclusions were conducted. The ore‐forming fluid is characterized as an H2O‐CO2‐NaCl system with medium‐high temperatures and low salinity. Four mineralization stages are identified, namely, feldspar‐quartz (stage 1); pyrite‐white quartz (stage 2); sulfide‐smoky grey quartz (stage 3); and carbonate‐quartz (stage 4). Three types of inclusions were distinguished, based on fluid composition, phase assemblages and mode of homogenization. Type A: H2O‐rich fluid inclusions show 2 phases (liquid H2O (LH2O) + vapour H2O (VH2O)) at room temperature and homogenize to the liquid phase. Type B: H2O‐CO2 fluid inclusions contain 2–3 phases (liquid H2O (LH2O) + vapour CO2 (VCO2); liquid H2O (LH2O) + liquid CO2 (LCO2)); liquid H2O (LH2O) + liquid CO2 (LCO2) + vapour CO2 (VCO2)) at room temperature and homogenized to the liquid H2O phase. Type C: H2O‐CO2 fluid inclusions show 2 phases (liquid H2O (LH2O) + liquid CO2 (LCO2) at room temperature and homogenize to a critical state. CO2 is clearly more enriched in the fluid inclusions of stages 2 and 3 than in stage 1. Stage 1 is dominated by type A (H2O‐rich) inclusions with homogenization temperatures (Th) of 220–359°C and salinities of 1.1–3.1 wt% NaCl equivalent. Type B (CO2‐rich) inclusions gradually increase in stages 2 and 3. The Th range of type B inclusions in stage 2 is 241–397°C with salinities of 2.2–6.9 wt% NaCl equivalent; the Th range of type A inclusions is 217–373°C with salinities of 1.2–8.1 wt% NaCl equivalent. The Th range of type B inclusions in stage 3 is 215–361°C with salinities of 2.9–6.1 wt% NaCl equivalent; the range of type A inclusions is 158–351°C with a salinity of 0.7–5.5 wt% NaCl equivalent. Stage 4 is characterized by type A with Th of 151–250°C and salinities of 0.9–8.3 wt% NaCl equivalent. The mapping results show that elements As, Te and Sb are more concentrated in vapour CO2 than in liquid H2O at room temperature, which suggests that vapour components are more able to transport elements when phase separation occurs. The SRXRF quantitative results show that Au, Cl, S and some other metals are obviously more enriched in the fluid inclusions of stages 2 and 3 than those in stage 1. Additionally, the contents of S in stages 1–3 are much lower than those of Cl, which suggests that gold might migrate mainly in the form of a gold‐chloride complex. Au is more enriched in type B fluid inclusions than in type A fluid inclusions, which suggests that the enrichment and migration of gold are closely related to CO2 and CO2 plays a critical role in the migration and enrichment of gold. The trace elements in the fluid have a similar change trend to those in the Yanshanian syenogranite distributed in the southeastern part of the mining area, which may provide some evidence for an intrusion‐related genesis for the Dongping gold deposit.

Nondestructive characterization of diseased Chinese chive leaves using X-ray intensity ratios with microbeam synchrotron radiation X-ray fluorescence spectrometry.

The Chinese chive (Allium tuberosum) is a core crop grown in Kochi Prefecture, Japan. However, withering symptoms occur during greenhouse growing, which have a negative impact on crop management Chinese chive leaves with physiological disorders (PD) or necrotic streak disease (ND) present with withering as typical blight symptoms. Excess or deficiency of elements may cause such withering in Chinese chive leaves with PD. Therefore, visualizing the elemental distribution in plant bodies may help clarify the cause of this withering. In this study, using synchrotron radiation X-ray fluorescence (SR-XRF) imaging, we examined the elemental distribution conditions in healthy Chinese chive leaves without withering, those that withered due to PD, and those that withered due to ND. Segmentation analysis of inductively coupled plasma-optical emission spectroscopy (ICP-OES) was performed on the SR-XRF imaged Chinese chive leaves and the data from the two analytical methods were compared. SR-XRF imaging provided more detailed data on elemental distribution compared with segmentation analysis using ICP-OES. Based on the SR-XRF imaging results, the X-ray intensity ratios for Ca/K, Fe/Mn, and Zn/Cu were calculated. These findings support that the Ca/K, Fe/Mn, and Zn/Cu X-ray intensity ratios can be used in the early detection of withered leaves and to predict the factors causing withering.

Fluid mineralization of the Dongtongyu gold deposit in the southern margin of North China craton: Evidence from microthermometry and composition of fluid inclusions

In this study, petrographic, microthermometric, and synchrotron radiation X-ray fluorescence (SRXRF) analyses of fluid inclusions were conducted to shed light on the mineralization mechanism of the Dongtongyu deposit and provide some evidence of the relationship among CO2, Au, and other ore elements (e.g., Cu, Fe, Zn, and Pb) in ore-forming fluids. The ore-forming fluid is characterized as the H2O–CO2–NaCl system with medium–high temperatures and low salinities. Four structural mineralization stages are distinguished: Pyrite-quartz (Stage 1), gold-quartz-pyrite (Stage 2), gold-quartz-polymetallic sulfide (Stage 3), and quartz-calcite (Stage 4). Fluid inclusions in Stages 1–3 are dominated by the H2O–CO2 type, and most of them contain liquid H2O and liquid CO2 at room temperature. The melting temperatures (Tm-CO2 = −82.1°C to −57.5°C) of solid CO2 in Stage 1 are relatively low. The values of Tm-CO2 in Stages 2–3 are quite close, with ranges of −60.5°C to −56.5°C and −59.2°C to −58.6°C, respectively. The melting temperatures of clathrate in Stages 1–3 are −2.7°C to +7.8°C, −5.5°C to +7.8°C, and +3.7°C to +7.2°C. The homogenization temperatures of the CO2 phase in the H2O–CO2 inclusions of the three stages are measured as −7.5°C to +31.7°C, −7.5°C to +29.3°C, and 7.1°C to +24.1°C. The total homogenization temperatures in Stages 1–3 are 180°C–394°C, 202°C–305°C, and 224°C–271°C, with salinities of 4.3 wt.%–18.2 wt% NaCl, 4.3 wt.%–20.0 wt% NaCl, and 5.3 wt.%–11.0 wt% NaCl, respectively. The laser Raman spectroscopy results show that the CO2–H2O inclusions in the quartz veins contain abundant CO2 and CH4. The SRXFR results show that most of the elements, especially As, Te, and Cu, are more enriched in liquid CO2 than in liquid H2O. The elements of Au, Fe, Ni, Cu, and Pb have higher concentrations in H2O–CO2-type fluid inclusions in Stage 2 than other fluid inclusions in Stages 1–2, suggesting that gold mineralization is closely related to CO2-rich fluids. During the fluid evolution process, fluid immiscibility is an important mineralization mechanism of gold. The increase in CO2 and CH4 and the decrease in the fluid temperature might promote fluid immiscibility.

Chemical Imaging – Is an Image Always Worth a Thousand Spectra?

Chemical images can be described as distribution maps that correlate the chemical information of an element or molecule, such as mass-to-charge ratio (m/z) or wavelength, with its intensity and/or concentration in a given sample. These images are usually obtained by mass spectrometry (MS) or optical spectroscopy techniques, where hundreds or thousands of spectra are initially acquired and dedicated image processing software is employed to construct and edit the final pictures, as well as selecting and annotating regions of interest in a sample, performing calibration procedures, etc. Mass spectrometry imaging (preferably abbreviated as MSI, to distinguish it from ion mobility spectrometry – IMS) is currently the most employed chemical imaging strategy, as can be noticed in the most recently published papers. Depending on the selected ionization technique, molecular or elemental images can be acquired. For molecular MSI, the classical matrix-assisted laser desorption/ionization (MALDI) is generally applied for imaging lipids, peptides and proteins, and the ambient ionization technique desorption electrospray ionization (DESI) is commonly applied for visualizing lipid distribution. In terms of elemental MSI, laser ablation inductively coupled plasma (LA-ICP) is undoubtedly the technique of choice, although nano-secondary ion mass spectrometry (nanoSIMS) can also be applied. Considering optical spectroscopy, the main techniques used nowadays are Raman and near-infrared radiation – NIR – spectroscopy for molecular imaging, and Synchrotron radiation X-ray fluorescence – SRXRF – and laser-induced breakdown spectroscopy – LIBS – for elemental imaging. Amongst these techniques, the best spatial resolutions are generally achieved by SRXRF (elemental imaging) and Raman spectroscopy (molecular imaging). Analytical chemistry advances in chemical imaging allow the acquisition of images with high spatial resolution, which is particularly interesting when studying specific regions or cell structures in a biological sample. For instance, in a Parkinson’s disease model, LA-ICP-MS images with good spatial resolution make the distinction of specific mouse brain regions possible and, consequently, the association of metal ion concentrations to each region,1 which is a relevant result considering micro-local metal speciation in neurodegenerative diseases. Nevertheless, there are some drawbacks in chemical imaging that demand further analytical development, such as the long analysis time and the lack of certified reference materials for quantitative analysis and method validation, as well as open-source software with advanced multivariate statistical analysis tools. Another obstacle to overcome concerns the integration of elemental and molecular imaging results. Since 2009, when one of the first review articles regarding the combination of these imaging approaches in a synergistic way was proposed by Becker and Jakubowski,2 until more recently described in reviews from 20203 and 2021,4 it has been possible to realize that there is still much work to be done in this field. This is mostly due to the fact that each imaging technique provides different spatial resolutions, making image superposition difficult, and also the absence of software and algorithms that allow the integration of different data sets in order to obtain trustworthy results and produce relevant study hypotheses. Besides that, the instrumentation for chemical imaging is rather costly and usually research groups are specialized in either molecular or elemental imaging. With these considerations, it is important to emphasize that the community involved in chemical imaging research should focus not only on the quality of the generated images in terms of resolution but also, if they are indeed worth a thousand spectra, on interpretation of the initial questions in a deep and holistic manner. After all, the main objective of chemical imaging is that the images represent how the process in question (disease, treatment, contamination, genetic modification, etc.) locally affects the system (biological, environmental, pharmaceutical sample) under study and, then, provide solutions for solving problems in different areas, such as forensic, environmental and life sciences.

Cardamine violifolia as a potential Hg hyperaccumulator and the cellular responses

Cardamine violifolia belongs to the Brassicaceae family and is a selenium (Se) hyperaccumulator found in Enshi, China. In this study, C. violifolia was found to accumulate mercury (Hg) in its roots and aboveground parts at concentrations up to 6000 μg/g. In the seedling and mature stages, the bioaccumulation factors (BAFS) of Hg reached 1.8–223, while the translocation factor (TF) for Hg reached 1.5. We observed a significant positive correlation between THg concentrations in plant tissues and those in the soil (r2 = 0.71–0.84). Synchrotron radiation X-ray fluorescence with focused X-ray (μ-SRXRF) showed that Hg was translocated from the roots to shoots through the vascular bundle and was transported through the leaf veins in leaves. Transmission electron microscopy showed that root cells were more tolerant to Hg than leaf cells. These findings provide insights into the mechanisms of Hg hyperaccumulation in C. violifolia. Overall, we demonstrated that C. violifolia is a promising Hg hyperaccumulator that may be used for phytoremediating Hg-contaminated farmlands.

Trace-element analysis of mineral grains in Ryugu rock fragment sections by synchrotron-based confocal X-ray fluorescence

A fundamental parameter-based quantification scheme for confocal XRF was applied to sub-micron synchrotron radiation X-ray fluorescence (SR-XRF) data obtained at the beamline P06 of the Deutsches Elektronen-Synchrotron (DESY, Hamburg, Germany) from two sections C0033-01 and C0033-04 that were wet cut from rock fragment C0033 collected from Cb-type asteroid (162173) Ryugu by JAXA’s Hayabusa2 mission. Trace-element quantifications show that C0033 bulk matrix is CI-like, whereas individual mineral grains (i.e., magnetite, pyrrhotite, dolomite, apatite and breunnerite) show, depending on the respective phase, minor to strong deviations. The non-destructive nature of SR-XRF coupled with a new PyMca (a Python toolkit for XRF data analysis)-based quantification approach, performed in parallel with the synchrotron experiments, proves to be an attractive tool for the initial analysis of samples from return missions, such as Hayabusa2 and OSIRIS-REx, the latter returning material from a B-type asteroid (101955) Bennu in 2023.Graphical

Elemental Composition of Skeletal Muscle Fibres Studied with Synchrotron Radiation X-ray Fluorescence (SR-XRF).

Diseases of the muscle tissue, particularly those disorders which result from the pathology of individual muscle cells, are often called myopathies. The diversity of the content of individual cells is of interest with regard to their role in both biochemical mechanisms and the structure of muscle tissue itself. These studies focus on the preliminary analysis of the differences that may occur between diseased tissues and tissues that have been recognised as a reference group. To do so, 13 samples of biopsied human muscle tissues were studied: 3 diagnosed as dystrophies, 6 as (non-dystrophic) myopathy and 4 regarded as references. From these sets of muscle biopsies, 135 completely measured muscle fibres were separated altogether, which were subjected to investigations using synchrotron radiation X-ray fluorescence (SR-XRF). Muscle fibres were analysed in terms of the composition of elements such as Br, Ca, Cl, Cr, Cu, Fe, K, Mn, P, S and Zn. The performed statistical tests indicate that all three groups (dystrophies—D; myopathies—M; references—R) show statistically significant differences in their elemental compositions, and the greatest impact, according to the multivariate discriminate analysis (MDA), comes from elements such as Ca, Cu, K, Cl and S.

Ice Coverage of the Laptev Sea and Air Temperature Variation during Recent Centuries: Observed Data and Reconstructions Using a Geochemical Proxy

Objective: The aim was to reconstruct the climatic parameters and ice of the Laptev Sea over the last centuries and to identify the causes of their variability. Background: The ice-free water area of the Arctic Ocean has increased considerably during the summer–autumn period in recent decades, which may be attributed to several climatic and oceanographic factors. Methods: The ice-free period duration and mean annual surface air temperature were reconstructed using the transfer function technique to compare hydrometeorological data and the chemical composition of bottom sediments accumulated during the observation period. This approach was based on sub-millimeter scanning of sediments using synchrotron radiation X-ray fluorescence. The results revealed a specific feature of the variations in the mean annual air temperature over the last 400 years in the Laptev Sea region, whereby higher (up to positive) temperature anomalies, were observed during the Little Ice Age. Some discrepancies in the ice coverage and climate fluctuations were observed during the period from the end of the Little Ice Age to the beginning of the period of accelerated ice-cover degradation in the Arctic (1850–1980). These discrepancies can be caused by the beginning of global warming, which have disturbed the natural cyclicality of atmospheric processes, whereas natural variations in ice coverage were more stable. Conclusion: A joint analysis of the reconstructed variations in air temperature and the duration of the ice-free period revealed the influence of atmospheric processes on the ice conditions of the Laptev Sea.

Non-targeted metallomics through synchrotron radiation X-ray fluorescence with machine learning for cancer screening using blood samples

Cancer is the leading cause of death in many countries. The development of new methods for early screening of cancers is highly desired. Targeted metallomics has been successfully applied in the screening of cancers through quantification of elements in the matrix, which is time consuming and requires combined techniques for the quantification due to the large elemental difference in the matrix. This work proposed a non-targeted metallomics (NTM) approach through synchrotron radiation based X-ray fluorescence (SRXRF) and machine learning algorithms (MLAs) for the screening of cancers. One hundred serum samples were collected from cancer patients who were confirmed by pathological examination with 100 matched serum samples from healthy volunteers. The serum samples were studied with SRXRF and the spectra from both groups were directly clarified through MLAs, which did not require the quantification of elements. The NTM approach through SRXRF and MLAs is fast (5s for data collection for one sample) and accurate (over 96% accuracy) for cancer screening. Besides, this approach can also identify the most affected elements in cancer samples like Ca, Zn and Ti as we found, which may shed lights on the drug development for cancer treatment. This NTM approach can also be applied through commercially available XRF instruments or ICP-TOF-MS with MLAs. It has the potential for the screening and prediction of other diseases like COVID-19 and neurodegenerative diseases in a high throughput and least invasive way.

Delivery of cisplatin and resiquimod in nanomicelles for the chemoimmunotherapy of ovarian cancer

BackgroundTo explore the effect and mechanism of delivery of cisplatin (CDDP) and resiquimod in nanomicelles for the chemoimmunotherapy of ovarian cancer in vivo and in vitro.MethodsPoly(l-glutamic acid)-graft-methoxypolyethylene glycols (PLG-g-mPEG) was used to carry cisplatin and resiquimod for the preparation of CDDP/resiquimod/PLG-g-mPEG. We determined the loading content (LC) and encapsulation efficiency (EE), and then observed the particle shape, particle size distribution and zeta potential. In this study, we recruited 30 healthy adult participants and isolated mononuclear cells, and they were randomly classified into a control group, a CDDP group, a resiquimod group, a CDDP/resiquimod/PLG-g-mPEG group and a IFN-γ + LPS group to identify macrophages markers in different polarization states. We conducted microprobe synchrotron radiation X-ray fluorescence (SRXRF) imaging to observe the cell uptake. Furthermore, we observed the effects of CDDP/resiquimod/PLG-g-mPEG on the growth and colony formation of SW626 cells and the expressions of apoptosis-associated genes and proteins. Tumor-bearing mouse models of ovarian cancer were prepared and randomized into a negative control group, a PLG-g-mPEG group, a CDDP group, a resiquimod group and a CDDP/resiquimod/PLG-g-mPEG group, so as to analyze the anti-cancer effect of CDDP/resiquimod/PLG-g-mPEG in vivo.ResultsThe LC and EE of CDDP/resiquimod/PLG-g-mPEG were 19.42% and 90.12%, respectively. Nanoparticles were uniform spherical in shape and closely arranged together, with a typical core–shell structure, and their average particle size and zeta potential were 82.36 nm and − 23.69 mV, respectively. When CDDP/resiquimod/PLG-g-mPEG group was compared with the control group, the positive expression rate of CD16 in the CDDP/resiquimod/PLG-g-mPEG group highly increased, whereas the positive expression rate of CD163 dramatically decreased. In the meantime, Arg1 and Mrc1 mRNA expressions significantly decreased whereas IL-12 and NOS2 mRNA expressions dramatically increased (P < 0.05). Elemental mapping of cells exhibited notable internalization of cisplatin delivered by CDDP/resiquimod/PLG-g-mPEG to cytoplasm. We compared the cell survival rate between the CDDP/resiquimod/PLG-g-mPEG group and the control group, the CDDP/resiquimod/PLG-g-mPEG group sharply reduced (P < 0.05). What’s more, the inhibitory effect got strengthened as the reaction time was prolonged, with the synergy coefficient of 0.31.ConclusionPLG-g-mPEG-loaded CDDP and resiquimod effectively achieves the targeted delivery of chemotherapy and immunotherapy, with a strong synergistic anti-cancer effect.

Cellular Detection of a Mitochondria Targeted Brominated Vinyl Triphenylamine Optical Probe (TP-Br) by X-Ray Fluorescence Microscopy.

Triphenylamine (TP) derivatives such as two-branch cationic vinylbenzimidazolium triphenylamine TP-2Bzim are promising turn-on fluorescent probes suitable for two-photon imaging, labelling mitochondria in live cells. Here, we designed two TP-2Bzim derivatives as bimodal probes suitable for X-ray fluorescence imaging. The conjugation of the TP core with a rhenium tricarbonyl moiety in the TP-RePyta probe altered the localisation in live cells from mitochondria to lysosomes. The introduction of bromine on the TP core generated the TP-Br probe retaining good photophysical properties and mitochondria labelling in live cells. The influence of calcium channels in the uptake of TP-Br was studied. Synchrotron Radiation X-ray Fluorescence (SXRF) imaging of bromine enabled the detection of TP-Br and suggested a negligible presence of the probe in an unbound state in the incubated cells, a crucial point in the development of these probes. This study paves the way towards the development of TP probes as specific organelle stainers suitable for SXRF imaging.