Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.648
Filtrar
1.
PLoS One ; 19(10): e0310845, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39441771

RESUMO

Zinc and selenium are essential minerals for human nutrition. Reliable biomarkers of zinc status and selenium status in humans are therefore important. This work investigates a novel portable X-ray fluorescence (XRF) method with the ability to rapidly assess zinc and selenium in nail clippings. This approach used a mono-energetic X-ray beam to excite characteristic X-rays from the clippings. Nail clippings were obtained from the Mother and Infant Nutrition Investigation (MINI), a study designed to assess nutrition in a population of women and their breastfed children in New Zealand. Twenty mother-infant pairings were selected to provide nail clippings at two time points (visit 1 at 3 months postpartum; visit 2 at 6 months postpartum). Nail clippings from each mother-infant pairing were divided into three groupings of clippings prior to analysis: those obtained from a big toe of the mother, those from the other toes of the mother, and those from the toes and fingers of the infant. Clippings were prepared and mounted prior to XRF measurement, providing four distinct fragments from each clipping grouping. These fragments were assessed by XRF using a measurement time of either 300 s (visit 1) or 180 s (visit 2). XRF results were determined through both an automated system output and an analysis of the X-ray energy spectrum. Following this assessment of zinc and selenium with the non-destructive XRF method, clippings were measured for zinc and selenium concentration using a "gold standard" technique of inductively coupled plasma mass spectrometry (ICP-MS). Mean ICP-MS concentrations ranged from 122 µg/g to 127 µg/g for zinc, and from 0.646 µg/g to 0.659 µg/g for selenium. Precision, assessed by a relative standard deviation of measurement, was superior for ICP-MS relative to XRF. For both zinc and selenium, XRF results were compared with ICP-MS concentrations. Linear equations of best fit were determined for each comparison between XRF and ICP-MS results. Coefficients of determination (r2) were stronger for zinc (from 0.74 to 0.95) than selenium (from 0.53 to 0.70). A decrease in XRF measurement time from 300 s to 180 s did not appear to adversely affect the correlation between XRF and ICP-MS results. Using the mono-energetic portable XRF method, the correlation of XRF zinc results with ICP-MS zinc concentrations was improved over previous findings, and selenium measurement was reported for the first time. The method may prove useful for future applications to trace element analysis using nail clippings as a biomarker.


Assuntos
Unhas , Selênio , Espectrometria por Raios X , Zinco , Humanos , Selênio/análise , Zinco/análise , Unhas/química , Feminino , Lactente , Espectrometria por Raios X/métodos , Adulto , Nova Zelândia , Estado Nutricional , Masculino
2.
Int J Mol Sci ; 25(19)2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39408586

RESUMO

Iron redistribution in the intestine after total body irradiation is an established phenomenon. However, in the literature, there are no reports about the use of X-ray fluorescence microscopy or equivalent techniques to generate semi-quantitative 2D maps of iron in sectioned intestine samples from irradiated mice. In this work, we used X-ray fluorescence microscopy (XFM) to map the elemental content of iron as well as phosphorus, sulfur, calcium, copper and zinc in tissue sections of the small intestine from eight-week-old BALB/c male mice that developed gastrointestinal acute radiation syndrome (GI-ARS) in response to exposure to 8 Gray of gamma rays. Seven days after irradiation, we found that the majority of the iron is localized as hot spots in the intercellular regions of the area surrounding crypts and stretching between the outer perimeter of the intestine and the surface cell layer of villi. In addition, this study represents our current efforts to develop elemental cell classifiers that could be used for the automated generation of regions of interest for analyses of X-ray fluorescence maps. Once developed, such a tool will be instrumental for studies of effects of radiation and other toxicants on the elemental content in cells and tissues. While XFM studies cannot be conducted on living organisms, it is possible to envision future scenarios where XFM imaging of single cells sloughed from the human (or rodent) intestine could be used to follow up on the progression of GI-ARS.


Assuntos
Raios gama , Camundongos Endogâmicos BALB C , Microscopia de Fluorescência , Animais , Raios gama/efeitos adversos , Camundongos , Masculino , Microscopia de Fluorescência/métodos , Ferro/metabolismo , Ferro/análise , Intestino Delgado/efeitos da radiação , Intestino Delgado/metabolismo , Intestinos/efeitos da radiação , Intestinos/patologia , Espectrometria por Raios X/métodos
3.
PLoS One ; 19(9): e0306795, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39231132

RESUMO

An improvement in the reliability and comparability of tissue characterization results is crucial for enabling further progress in cancer detection and the assessment of therapeutic effects. This can only be achieved by integrating quantitative methods into well-established qualitative characterization routines. This case study presents a hybrid metrological approach for tissue characterisation including vibrational Fourier Transform InfraRed (FTIR) spectroscopy and traceable reference-free X-Ray Fluorescence analysis (XRF). Through the combination of spatially resolved qualitative molecular information with quantitative elemental concentrations an all-encompassing sample characterisation can be provided. The study was performed on tissue sections of syngeneic murine pancreatic ductal adenocarcinoma KPC (KrasG12D/+; Trp53R172H/+; Pdx-1-Cre) tumours ex-vivo. Sections from healthy pancreatic tissues, sham-exposed tumours and tumours subjected to low dose radiotherapy treatment (2 Gray and 6 Gray) were analysed using both methods. Additional sample integrity studies using Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy at the carbon and nitrogen K-edges were performed to assess the effect of sample aging and XRF investigations on the samples. Results showed an increase in the concentrations of elemental biomarkers, including S, K and amide I structures in malignant pancreatic tissue compared to healthy pancreatic tissue. The exposure of tumours to 6 Gy radiation decreases the levels of these elements towards a phenotype seen in the healthy pancreas. A protocol for hybrid investigations is presented, with emphasis on the sample preparation, minimizing the impact of consecutive applied methods on their measurands, and ensuring the compatibility and reliability of achieved results. The study demonstrates the cancer recognition capabilities, and the sensitivity for low dosage radiotherapy treatment monitoring for each method individually and assesses the potential of combining molecular fingerprinting with non-destructive quantitative elemental information for tissue sample characterization.


Assuntos
Neoplasias Pancreáticas , Espectrometria por Raios X , Animais , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/radioterapia , Camundongos , Espectrometria por Raios X/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/diagnóstico por imagem
4.
Sci Rep ; 14(1): 20377, 2024 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223290

RESUMO

Portable X-ray Fluorescence probe (pXRF) is a tool used to measure many elements quickly and efficiently in soil with minimal sample preparation. Although this sensing technique has been widely used to determine total elemental concentrations, it has not been calibrated for plant-available nutrient predictions. We evaluated the potential of using pXRF for fast plant-available nutrient quantification. Two experiments were conducted in soils treated with two types of biochars to obtain a practical range of soil pH (5.5 - 8.0) and organic carbon (2.0 - 5.5%). Biochars applied were derived from switchgrass (SGB) and poultry litter (PLB). The first experiment received biochars at application rates up to 8% (w/w) and had no plants. The second experiment had up to 4% of SGB or PLB planted with ryegrass (Lolium perenne). Linear regression (LR), polynomial regression (PolR), power regression (PowR), and stepwise multiple linear regression (SMLR) were the models tested. Regardless of the extraction method, phosphorus (P) showed a strong relationship between pXRF and several laboratory extraction methods; however, K prediction via pXRF was sensitive to the plant factor. The optimum soil available-P corresponding to the maximum P uptake in plant tissues can be assessed with pXRF. The LR was inconsistent for calcium (Ca), sulfur (S), and copper (Cu) and non-significant for magnesium (Mg), iron (Fe), and zinc (Zn). Our results showed that pXRF is applicable to estimate P availability in soils receiving organic amendments. More evaluations are needed with diverse soil types to confirm the findings before using pXRF for fertilizer recommendation.


Assuntos
Carvão Vegetal , Solo , Espectrometria por Raios X , Solo/química , Carvão Vegetal/química , Espectrometria por Raios X/métodos , Nutrientes/análise , Fósforo/análise , Lolium/química , Lolium/metabolismo , Plantas/química , Plantas/metabolismo
5.
Metallomics ; 16(10)2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39271453

RESUMO

Nitrogen-fixing cyanobacteria bind atmospheric nitrogen and carbon dioxide using sunlight. This experimental study focused on a laboratory-based model system, Anabaena sp., in nitrogen-depleted culture. When combined nitrogen is scarce, the filamentous prokaryotes reconcile photosynthesis and nitrogen fixation by cellular differentiation into heterocysts. To better understand the influence of micronutrients on cellular function, 2D and 3D synchrotron X-ray fluorescence mappings were acquired from whole biological cells in their frozen-hydrated state at the Bionanoprobe, Advanced Photon Source. To study elemental homeostasis within these chain-like organisms, biologically relevant elements were mapped using X-ray fluorescence spectroscopy and energy-dispersive X-ray microanalysis. Higher levels of cytosolic K+, Ca2+, and Fe2+ were measured in the heterocyst than in adjacent vegetative cells, supporting the notion of elevated micronutrient demand. P-rich clusters, identified as polyphosphate bodies involved in nutrient storage, metal detoxification, and osmotic regulation, were consistently co-localized with K+ and occasionally sequestered Mg2+, Ca2+, Fe2+, and Mn2+ ions. Machine-learning-based k-mean clustering revealed that P/K clusters were associated with either Fe or Ca, with Fe and Ca clusters also occurring individually. In accordance with XRF nanotomography, distinct P/K-containing clusters close to the cellular envelope were surrounded by larger Ca-rich clusters. The transition metal Fe, which is a part of nitrogenase enzyme, was detected as irregularly shaped clusters. The elemental composition and cellular morphology of diazotrophic Anabaena sp. was visualized by multimodal imaging using atomic force microscopy, scanning electron microscopy, and fluorescence microscopy. This paper discusses the first experimental results obtained with a combined in-line optical and X-ray fluorescence microscope at the Bionanoprobe.


Assuntos
Fixação de Nitrogênio , Espectrometria por Raios X/métodos , Anabaena/metabolismo , Anabaena/ultraestrutura , Nitrogênio/metabolismo , Cianobactérias/metabolismo , Cianobactérias/ultraestrutura
6.
Anal Chim Acta ; 1324: 343098, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39218578

RESUMO

BACKGROUND: Arsenic, classified as a priority pollutant and human carcinogen by the IARC, is subject to stringent regulatory limits in food and water. Among various arsenic species found in water samples, arsenite (As(III)) is identified as the most toxic form. Given the limitations of conventional spectroscopic techniques in speciation analysis, there is a crucial need for innovative and sustainable methodologies that enable arsenic speciation. Simplifying these methodologies is essential for widespread applicability and effective environmental monitoring. RESULTS: This study proposes a simple and cost-effective analytical methodology for speciating inorganic arsenic in water samples. The method involves extracting As(III) into a polymer inclusion membrane (PIM) containing the extractant Cyanex 301 (bis(2,4,4-trimethylpentyl) dithiophosphinic acid), followed by analysis using energy dispersive X-ray fluorescence (EDXRF) spectrometry. The concentration of arsenate was measured after a reduction step using a thiosulfate/iodide mixture. This simple methodology allows a limit of quantification for trivalent arsenic (2 µg L-1), which is well below the World Health Organization's recommended maximum permissible level of As in drinking water (10 µg L-1). The method that is developed allows the determination of As at trace levels in waters with naturally occurring arsenic. SIGNIFICANCE AND NOVELTY: This study represents a significant advance in the field, providing a novel and efficient methodology for arsenic speciation analysis in water samples. By combining the advantages of polymer inclusion membrane (PIM) extraction with energy dispersive X-ray fluorescence (EDXRF) spectrometry, this study offers a cost-effective and environmentally friendly approach to address the critical issue of arsenic contamination in water sources, thereby contributing to enhanced environmental monitoring and public health protection.


Assuntos
Arsênio , Polímeros , Espectrometria por Raios X , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Polímeros/química , Arsênio/análise , Espectrometria por Raios X/métodos , Membranas Artificiais
7.
Eur Endod J ; 9(4): 210-217, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39213452

RESUMO

OBJECTIVE: This study aimed to address the lack of comparative analyses of newly developed bioceramic materials by examining the chemical composition, thermodynamic profile, and microscopic surface features of three bioceramic putties: EndoSequence BC Root Repair Material Fast Set Putty (ESRRM-FS), BIO-C Repair (BCR), and Cera Putty (CP). METHODS: Samples of each of the three bioceramic putty obtained directly from manufacturers were prepared for analysis of physicochemical composition and microscopic features by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) imagery, and energy-disper-sive X-ray spectroscopy (EDS). The data obtained was qualitatively and statistically analysed. Statistical signif-icance was determined at p≤0.05. RESULTS: DSC analysis indicated a standard polymeric vehicle for BCR and CP, coinciding with the polyethene glycol (PEG) thermal profile; the polymeric vehicle in ESRRM-FS remains to be identified. The material with the highest heat capacity was CP (p<0.05), followed by ESRRM-FS and BCR. TGA revealed an inflexion point at 394.12 ºC for ESRRM-FS, which may correspond to the mass loss of dihydroxylation of calcium hydroxide. A more homogenous structure was observed in scanning electron microscopy (SEM) images for ESRRM-FS. EDS analysis indicated BCR had minimal amounts of aluminium (2.06+-0.44%) and a lower percentage of cal-cium than ESRRM-FS (9.11+-1.38% vs. 11.3+-0.87%). CP was composed of aluminium (49.35+-7.01%), carbon (30.65+-5.62%), and oxygen (16.75+-2.44%); no silicon was identified. ESRRM-FS had no aluminium present and the highest calcium percentage (11.3+-0.87%) (p<0.05). CONCLUSION: BCR is a Portland cement-derived material with a lower percentage of calcium than ESRRM-FS and minimal amounts of aluminium. CP is a monocalcium aluminate cement, mainly composed of aluminium, carbon, and oxygen. ESRRM-FS is a biphasic material with the highest calcium percentage among all materials studied and no aluminium.


Assuntos
Cerâmica , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Varredura/métodos , Varredura Diferencial de Calorimetria , Materiais Restauradores do Canal Radicular/química , Espectrometria por Raios X/métodos , Termogravimetria/métodos , Materiais Biocompatíveis/química , Teste de Materiais/métodos , Propriedades de Superfície , Fosfatos de Cálcio , Combinação de Medicamentos , Óxidos , Silicatos
8.
Nutrients ; 16(15)2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39125428

RESUMO

Placental health and foetal development are dependent upon element homeostasis. Analytical techniques such as mass spectroscopy can provide quantitative data on element concentrations in placental tissue but do not show spatial distribution or co-localisation of elements that may affect placental function. The present study used synchrotron-based X-ray fluorescence microscopy to elucidate element content and distribution in healthy and pathological placental tissue. The X-ray fluorescence microscopy (XFM) beamline at the Australian Synchrotron was used to image trace metal content of 19 placental sections from healthy term (n = 5, 37-39 weeks), foetal growth-restricted (n = 3, <32 weeks, birth weight <3rd centile), postdate (n = 7, >41 completed weeks), and stillbirth-complicated pregnancies (n = 4, 37-40 weeks). Samples were cryo-sectioned and freeze-dried. The concentration and distribution of fourteen elements were detected in all samples: arsenic, bromine, calcium, chlorine, copper, iron, molybdenum, phosphorous, potassium, rubidium, selenium, strontium, sulphur, and zinc. The elements zinc, calcium, phosphorous, and strontium were significantly increased in stillbirth placental tissue in comparison to healthy-term controls. Strontium, zinc, and calcium were found to co-localise in stillbirth tissue samples, and calcium and strontium concentrations were correlated in all placental groups. Molybdenum was significantly decreased in stillbirth, foetal growth-restricted, and postdate placental tissue in comparison to healthy-term samples (p < 0.0001). Synchrotron-based XFM reveals elemental distribution within biological samples such as the placenta, allowing for the co-localisation of metal deposits that may have a pathological role. Our pilot study further indicates low concentrations of placental molybdenum in pregnancies complicated by foetal growth restriction, postdate delivery, and stillbirth.


Assuntos
Retardo do Crescimento Fetal , Molibdênio , Placenta , Natimorto , Síncrotrons , Humanos , Feminino , Gravidez , Molibdênio/análise , Placenta/metabolismo , Retardo do Crescimento Fetal/metabolismo , Microscopia de Fluorescência , Oligoelementos/análise , Oligoelementos/metabolismo , Adulto , Espectrometria por Raios X/métodos
9.
Environ Geochem Health ; 46(9): 352, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080027

RESUMO

Our study aimed to assess the soil quality in Punjab's Hoshiarpur district through a meticulous analysis of nutrient and elemental composition. Using a variety of analytical techniques, including Neutron Activation Analysis (NAA), external Particle-induced Gamma-ray Emission (PIGE) an Ion beam analysis Technique, and energy-dispersive X-ray fluorescence (ED-XRF), we delved into soil characterization for 22 agricultural soil samples in the Punjab region. Within the NAA framework, utilizing the Pneumatic Carrier Facility and the self-serve facility at Dhruva reactor in Mumbai, a brief 1-min irradiation procedure identified pivotal elements-Na, Mg, V, Al, Mn, and K. Conversely, an extended neutron irradiation process of approximately 4 h within the self-serve facility enabled the estimation of nearly 12 elements, including Rare Earth Elements (REEs), Transition elements, and other significant elements. The external PIGE technique quantified low Z elements (Na, Mg, Al, and Si), contributing to our analytical arsenal. Rigorously validating both NAA and PIGE methodologies, we compared results meticulously against established geological standard reference materials-specifically USGS RGM-1 and USGS AGV-1.Instrumental in elemental analysis, ED-XRF spectroscopy fortified our investigative endeavors by quick assessment of ten crucial elements. The elemental analysis revealed notable accumulations of Mn and Zn in the soil, surpassing the suggested permissible limits, whereas Co, Cr, and Pb were found to be within the recommended thresholds set by WHO/UNEP. Beyond elemental profiling, our study extended to estimate the accumulation levels of various elements utilizing ecological risk factors such as Contamination Factor, Potential Ecological Risk Index, Pollution Load Index, and Geoaccumulation Factor. Our findings highlighted significant accumulation of REEs including La, Sm and Yb.. This evaluation sheds new light on the interplay between soil composition and environmental health, emphasizing the need for advanced accessible agricultural technologies to prevent and forecast contaminant discharge in arable soil. This commitment aligns with our broader goal of advancing sustainable practices in soil management.


Assuntos
Agricultura , Monitoramento Ambiental , Solo , Solo/química , Índia , Monitoramento Ambiental/métodos , Análise de Ativação de Nêutrons , Espectrometria por Raios X/métodos , Poluentes do Solo/análise
10.
Environ Manage ; 74(5): 958-969, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38985338

RESUMO

The main objective of the current study was to use seven lots in Hartford, CT that are planned for community reuse to determine the optimal sampling density that allows for the detection of hotspots of lead pollution while limiting the labor of the sampling process. The sampling density was investigated using soil Pb measured by in situ X-ray Fluorescence as the indicator to evaluate soil health, with a new threshold of 200-mg/kg proposed by the USEPA in January of 2024. Even though this study takes place in an urban setting, where the new USEPA policy requires the use of a 100-mg/kg threshold for Pb due to the fact that there are other identifiable sources of the contaminant, only the 200-mg/kg threshold is discussed because it is evident from the analysis that compliance of a 100 mg/kg threshold in urban plots is highly unlikely (five out of seven sites would require complete site excavation prior to reuse). Using the inverse distance weighted geospatial interpolation of in situ pXRF determined lead measurements, grid sampling resolutions of 3-m, 4-m, 5-m, 6-m, 8-m, 10-m, and 12-m were compared. Ultimately, the case study finds that the largest grid resolution that can be implemented for soil screening to maintain hotspots of pollution to properly inform soil management decisions is a 6-m grid, or a density of approximately 1/36-m2.


Assuntos
Monitoramento Ambiental , Chumbo , Poluentes do Solo , Solo , Poluentes do Solo/análise , Solo/química , Monitoramento Ambiental/métodos , Chumbo/análise , Cidades , Espectrometria por Raios X/métodos
11.
PLoS One ; 19(7): e0302563, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985774

RESUMO

Research on personal adornments depends on the reliable characterisation of materials to trace provenance and model complex social networks. However, many analytical techniques require the transfer of materials from the museum to the laboratory, involving high insurance costs and limiting the number of items that can be analysed, making the process of empirical data collection a complicated, expensive and time-consuming routine. In this study, we compiled the largest geochemical dataset of Iberian personal adornments (n = 1243 samples) by coupling X-ray fluorescence compositional data with their respective X-ray diffraction mineral labels. This allowed us to develop a machine learning-based framework for the prediction of bead-forming minerals by training and benchmarking 13 of the most widely used supervised algorithms. As a proof of concept, we developed a multiclass model and evaluated its performance on two assemblages from different Portuguese sites with current mineralogical characterisation: Cova das Lapas (n = 15 samples) and Gruta da Marmota (n = 10 samples). Our results showed that decisión-tres based classifiers outperformed other classification logics given the discriminative importance of some chemical elements in determining the mineral phase, which fits particularly well with the decision-making process of this type of model. The comparison of results between the different validation sets and the proof-of-concept has highlighted the risk of using synthetic data to handle imbalance and the main limitation of the framework: its restrictive class system. We conclude that the presented approach can successfully assist in the mineral classification workflow when specific analyses are not available, saving time and allowing a transparent and straightforward assessment of model predictions. Furthermore, we propose a workflow for the interpretation of predictions using the model outputs as compound responses enabling an uncertainty reduction approach currently used by our team. The Python-based framework is packaged in a public repository and includes all the necessary resources for its reusability without the need for any installation.


Assuntos
Minerais , Minerais/análise , Minerais/química , Algoritmos , Portugal , Difração de Raios X , Espectrometria por Raios X/métodos , Humanos , Aprendizado de Máquina , Aprendizado de Máquina Supervisionado
12.
Molecules ; 29(13)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38999099

RESUMO

Metal sub-microparticles (SMPs) and nanoparticles (NPs) presence in food is attributable to increasing pollution from the environment in raw materials and finished products. In the present study, a multifaceted analytical strategy based on Environmental Scanning Electron Microscopy and High-Angle Annular Dark-Field-Scanning Transmission Electron Microscopy coupled with Energy-Dispersive X-ray Spectroscopy (ESEM-EDX, HAADF-STEM-EDX) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was proposed for the detection and characterization of metal and metal-containing SMPs and NPs in durum wheat samples, covering a size measurement range from 1 nm to multiple µm. ESEM-EDX and ICP-MS techniques were applied for the assessment of SMP and NP contamination on the surface of wheat grains collected from seven geographical areas characterized by different natural and anthropic conditions, namely Italy, the USA, Australia, Slovakia, Mexico, Austria, and Russia. ICP-MS showed significant differences among the mean concentration levels of metals, with the USA and Italy having the highest level. ESEM-EDX analysis confirmed ICP-MS concentration measurements and measured the highest presence of particles < 0.8 µm in size in samples from Italy, followed by the USA. Less marked differences were observed when particles < 0.15 µm were considered. HAADF-STEM-EDX was applied to a selected number of samples for a preliminary assessment of internal contamination by metal SMPs and NPs, and to expand the measurable particle size range. The multifaceted approach provided similar results for Fe-containing SMPs and NPs. ICP-MS and ESEM-EDX also highlighted the presence of a significant abundance of Ti- and Al-containing particles, while for STEM-EDX, sample preparation artifacts complicated the interpretation. Finally, HAADF-STEM-EDX results provided relevant information about particles in the low nm range, since, by applying this technique, no particles smaller than 50 nm were observed in accordance with ESEM-EDX.


Assuntos
Espectrometria de Massas , Nanopartículas Metálicas , Triticum , Triticum/química , Nanopartículas Metálicas/química , Espectrometria de Massas/métodos , Espectrometria por Raios X/métodos , Tamanho da Partícula , Metais/análise , Metais/química , Grão Comestível/química , Microscopia Eletrônica de Varredura
13.
Methods Mol Biol ; 2839: 43-52, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39008247

RESUMO

Characterizing the two- and three-dimensional distribution of trace metals in biological specimens is key to better understand their role in biological processes. Iron (Fe) is of particular interest in these trace metals due to its widespread role in maintaining cellular health and preventing disease. X-ray fluorescence microscopy (XFM) is emerging as the method of choice for investigators to interrogate the cellular and subcellular distribution of Fe. XFM utilizes the intrinsic X-ray fluorescence properties of each element to produce quantitative 2D and 3D distributions of trace metals within a sample. Herein, methods for sample preparation of cells and tissue for the determination of Fe distribution by XFM are described.


Assuntos
Ferro , Microscopia de Fluorescência , Ferro/análise , Ferro/metabolismo , Microscopia de Fluorescência/métodos , Animais , Humanos , Espectrometria por Raios X/métodos , Raios X
14.
Radiat Prot Dosimetry ; 200(11-12): 1228-1232, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016488

RESUMO

Medicinal plants of the Moraceae family, such as Ficus racemosa linn, have been traditionally used in the North Karnataka region for treating various ailments. This study aims to analyze the elemental composition and nano-micro structural morphology of selected species of Moraceae family medicinal plants, focusing on their potential therapeutic applications. Samples were collected from the Dharwad and Gadag districts in North Karnataka. The surface morphology at nano and micro levels was examined using a field emission scanning electron microscope, while the elemental composition was analyzed through energy-dispersive X-ray spectroscopy. The study emphasizes the detailed examination of the specific weight percent of elemental concentration and the morphological features observed. The analysis revealed fine, irregularly shaped particles with an average diameter of 20 to 50 µm on the plant surface. Elemental composition analysis showed the presence of Mg, Al, Si, Cl, K, Ca, Mn, Fe, Cu, and Zn within WHO-recommended limits.


Assuntos
Plantas Medicinais , Espectrometria por Raios X , Plantas Medicinais/química , Espectrometria por Raios X/métodos , Microscopia Eletrônica de Varredura
15.
Environ Monit Assess ; 196(8): 765, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39073501

RESUMO

Marginalized communities experience barriers that can prevent soil monitoring efforts and knowledge transfer. To address this challenge, this study compared two analytical methods: portable X-ray fluorescence spectroscopy (pXRF, less time, cost) and inductively coupled plasma mass spectrometry (ICP-MS, "gold standard"). Surface soil samples were collected from residential sites in Arizona, USA (N = 124) and public areas in Troy, New York, USA (N = 33). Soil preparation differed between groups to account for community practice. Statistical calculations were conducted, paired t test, Bland-Altman plot, and a two-way ANOVA indicated no significant difference for As, Ba, Ca, Cu, Mn, Pb, and Zn concentrations except for Ba in the t test. Iron, Ni, Cr, and K were statistically different for Arizona soils and V, Ni, Fe, and Al concentrations were statistically different for New York soils. Zinc was the only element with high R2 and low p value. Pollution load index (PLI), enrichment factors (EF), and geo-accumulation index (Igeo) were calculated for both methods using U.S. Geological Survey data. The PLI were > 1, indicating soil pollution in the two states. Between pXRF and ICP-MS, the Igeo and EF in Arizona had similar degree of contamination for most elements except Zn in garden and Pb in yard, respectively. For New York, the Igeo of As, Cu, and Zn differed by only one classification index between the two methods. The pXRF was reliable in determining As, Ba, Ca, Cu, Mn, Pb, and Zn in impacted communities. Therefore, the pXRF can be a cost-effective alternative to using ICP-MS techniques to screen soil samples for several environmentally relevant contaminants to protect environmental public health.


Assuntos
Monitoramento Ambiental , Metais , Poluentes do Solo , Solo , Espectrometria por Raios X , Poluentes do Solo/análise , Monitoramento Ambiental/métodos , Espectrometria por Raios X/métodos , Arizona , Metais/análise , Solo/química , New York , Reprodutibilidade dos Testes , Espectrometria de Massas/métodos , Metais Pesados/análise
16.
J Environ Sci (China) ; 145: 88-96, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38844326

RESUMO

Conventionally, soil cadmium (Cd) measurements in the laboratory are expensive and time-consuming, involving complex processes of sample preparation and chemical analysis. This study aimed to identify the feasibility of using sensor data of visible near-infrared reflectance (Vis-NIR) spectroscopy and portable X-ray fluorescence spectrometry (PXRF) to estimate regional soil Cd concentration in a time- and cost-saving manner. The sensor data of Vis-NIR and PXRF, and Cd concentrations of 128 surface soils from Yunnan Province, China, were measured. Outer-product analysis (OPA) was used for synthesizing the sensor data and Granger-Ramanathan averaging (GRA) was applied to fuse the model results. Artificial neural network (ANN) models were built using Vis-NIR data, PXRF data, and OPA data, respectively. Results showed that: (1) ANN model based on PXRF data performed better than that based on Vis-NIR data for soil Cd estimation; (2) Fusion methods of both OPA and GRA had higher predictive power (R2) = 0.89, ratios of performance to interquartile range (RPIQ) = 4.14, and lower root mean squared error (RMSE) = 0.06, in ANN model based on OPA fusion; R2 = 0.88, RMSE = 0.06, and RPIQ = 3.53 in GRA model) than those based on either Vis-NIR data or PXRF data. In conclusion, there exists a great potential for the combination of OPA fusion and ANN to estimate soil Cd concentration rapidly and accurately.


Assuntos
Cádmio , Monitoramento Ambiental , Poluentes do Solo , Solo , Espectroscopia de Luz Próxima ao Infravermelho , Cádmio/análise , Poluentes do Solo/análise , Solo/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , China , Monitoramento Ambiental/métodos , Espectrometria por Raios X/métodos , Redes Neurais de Computação , Estudos de Viabilidade
17.
Arch Pathol Lab Med ; 148(7): e154-e169, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38918006

RESUMO

CONTEXT.­: Overexposure to respirable coal mine dust can cause severe lung disease including progressive massive fibrosis (PMF). Field emission scanning electron microscopy with energy dispersive x-ray spectroscopy (FESEM-EDS) has been used for in situ lung dust particle analysis for evaluation of disease etiology. Automating such work can reduce time, costs, and user bias. OBJECTIVE.­: To develop and test an automated FESEM-EDS method for in situ analysis of inorganic particles in coal miner lung tissue. DESIGN.­: We programmed an automated FESEM-EDS procedure to collect particle size and elemental data, using lung tissue from 10 underground coal miners with PMF and 4 control cases. A statistical clustering approach was used to establish classification criteria based on particle chemistry. Data were correlated to PMF/non-PMF areas of the tissue, using corresponding brightfield microscopy images. Results for each miner case were compared with a separate corresponding analysis of particles recovered following tissue digestion. RESULTS.­: In situ analysis of miner tissues showed higher particle number densities than controls and densities were generally higher in PMF than non-PMF areas. Particle counts were typically dominated by aluminum silicates with varying percentages of silica. Compared to digestion results for the miner tissues, in situ results indicated lower density of particles (number per tissue volume), larger size, and a lower ratio of silica to total silicates-probably due to frequent particle clustering in situ. CONCLUSIONS.­: Automated FESEM-EDS analysis of lung dust is feasible in situ and could be applied to a larger set of mineral dust-exposed lung tissues to investigate specific histologic features of PMF and other dust-related occupational diseases.


Assuntos
Minas de Carvão , Poeira , Pulmão , Microscopia Eletrônica de Varredura , Exposição Ocupacional , Espectrometria por Raios X , Humanos , Espectrometria por Raios X/métodos , Poeira/análise , Pulmão/patologia , Pulmão/química , Exposição Ocupacional/análise , Exposição Ocupacional/efeitos adversos , Masculino , Tamanho da Partícula
18.
STAR Protoc ; 5(2): 103104, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38861383

RESUMO

Approaches for detecting micro(nano)plastics (MNPs) released from intravenous infusion products (IVIPs) are vital for evaluating the safety of both IVIPs and their derived MNPs on human health, yet current understanding is limited. Here, we present a protocol for detecting polyvinyl chloride (PVC) MNPs by combining Raman spectroscopy, scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (SEM-EDS), and pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). We describe steps for collecting, pretreating, and measuring PVC MNPs released from IVIPs. For complete details on the use and execution of this protocol, please refer to Li et al.1.


Assuntos
Análise Espectral Raman , Análise Espectral Raman/métodos , Infusões Intravenosas , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cloreto de Polivinila/química , Humanos , Microscopia Eletrônica de Varredura/métodos , Espectrometria por Raios X/métodos , Plásticos/química
19.
J Environ Radioact ; 278: 107479, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38905880

RESUMO

This work responds to the growing global demand for food, which requires improvements in agricultural production and sustainable management of natural resources. The focus is on soil erosion as a critical element in preserving agricultural productivity. From this perspective, the levels of radionuclides and chemical elements present in the soil, quantified through Gamma-Rays Spectrometry (GRS) and Energy Dispersive X-ray Fluorescence (EDXRF), were used to investigate soil redistribution over time. 27 soil samples ranging from 0 to 30 cm in depth were collected in an agricultural plot located in southern Brazil. Quantitative analysis indicated high mean concentrations of Fe (161 ± 7 gkg-1), Al (110 ± 17 gkg-1), Ca (2.6 ± 0.5 gkg-1), Mn (2.4 ± 0.3 gkg-1) and K (543 ± 165 mgkg-1) in comparison with the other detected elements. The quantification of 137Cs provided a mean inventory of 27 ± 17 Bqm-2. Using the proportional model, an estimated gross erosion rate of 28.2 tonha-1year-1 and a net soil deposition of 6.6 tonha-1year-1 were calculated. Therefore, a net soil loss of 21.6 tonha-1year-1 was experienced within the agricultural plot studied. The data set combination of both techniques with Principal Component Analysis (PCA) revealed correlations between the variables studied and the soil erosion dynamics. The PCA showed a tendency to separate the samples according to their sampling depth. Moreover, 137Cs behavior in soil proved to be similar to the behavior of elements found in fertilizers, like K. On the other hand, the individual influence of 137Cs was not enough to cause significant changes in the samples distribution in the scores plot, highlighting EDXRF as a promising technique to complement soil erosion studies.


Assuntos
Raios gama , Monitoramento de Radiação , Poluentes Radioativos do Solo , Solo , Poluentes Radioativos do Solo/análise , Solo/química , Brasil , Monitoramento de Radiação/métodos , Radioisótopos de Césio/análise , Espectrometria gama , Espectrometria por Raios X/métodos , Agricultura/métodos , Raios X
20.
Int J Legal Med ; 138(6): 2587-2593, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38898153

RESUMO

The analysis of traces of injuries can be difficult in cases of charred human remains since the alteration and fragmentation are high. The aim of this study is to explore the use of X-Ray Fluorescence (XRF) technique as a screening tool for detecting and analyzing gunshot residues (GSR) on cremated and highly fragmented materials, as it is a technique that allows for fast qualitative investigations without altering the sample or requiring sample preparation. The study was carried out on two steps: firstly, on completed skeletonized bones to verify if GSR survive to burning; secondly, we considered a more realistic situation, in which soft tissues were present before the shooting. To this aim, nine adult bovine ribs, four retaining soft tissue, five completely skeletonized, were subjected to a shooting test using two types of 9 mm projectiles (jacketed and unjacketed bullets). The ribs were then burnt until complete calcination in an electric furnace. The entry wound of each rib was analyzed using XRF, revealing traces of GSR. The XRF analysis showed that all samples, except for one, contain Pb and/or Sb near the lesion. Furthermore, the samples hit by unjacketed bullets had a more significant presence of Pb in macroscopic yellow areas, which persisted when moving away from the gunshot. These findings could pave the way for the use of XRF technology, mostly when a fast and immediate scan must be done on osteologic materials by a conservative method.


Assuntos
Antimônio , Balística Forense , Chumbo , Costelas , Espectrometria por Raios X , Ferimentos por Arma de Fogo , Ferimentos por Arma de Fogo/patologia , Animais , Espectrometria por Raios X/métodos , Costelas/lesões , Costelas/química , Bovinos , Balística Forense/métodos , Chumbo/análise , Antimônio/análise , Cremação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA