Total Reflection X-ray Fluorescence Spectrometer Research Articles

Effects of surface property on loading octaaza bis-α-diimine Ni complex, charge separation, and H2 production activity of MnS@ZnS photocatalysts

The MnS@ZnS photocatalyst was prepared using a microwave-assisted solvothermal method. Then, the octaaza bis-α-diimine Ni complex was loaded to prepare a composite photocatalyst. The adsorption of metal complex on photocatalyst depends on the anchoring groups of the Ni complex and the colloidal surface charge of the photocatalyst. The effects of the zeta potential of MnS and MnS@ZnS photocatalysts on the loading of Ni complex, separation of photogenerated carriers, and activity of Ni complex-modified composite photocatalysts were studied. The loading of NiC complex in photocatalysts was analyzed by Raman spectra, TEM line scan, mapping images, and total reflection x-ray fluorescence spectrometer. MnS@ZnS photocatalyst exhibits negative zeta potential that provides a strong electrostatic attraction force between photocatalysts and the Ni complex (Columb attraction), leading to increased Ni complex loading. MnS@ZnS/Ni complex exhibits better photocatalytic activity than MnS/Ni complex. Loading the Ni complex facilitates the photosensitization of photocatalysts, resulting in improved light absorbance. Besides, the electron-hole separation was further improved because the Ni complex acted as a redox mediator, enabling the transfer of electrons from MnS@ZnS to the Ni complex. The H2 production activity of MnS@ZnS/Ni complex photocatalyst reaches 3997 μmol h−1g−1, which is 1.72 times the pristine MnS.

Effect of sample carriers on analytical parameters in total reflection X-ray fluorescence - a tool for multi-trace elemental analysis

The Total reflection X-ray Fluorescence technique is increasingly popular for its simplicity and rapid elemental screening. This study evaluates the various analytical parameters including spectroscopic resolution, absolute sensitivity, relative element sensitivity, lowest limits of detection, accuracy and precision of the Total reflection X-ray Fluorescence spectrometer. This evaluation is conducted using quartz and acrylic sample carriers with mono and multi-element standards. Notably, the quartz sample carrier demonstrated excellent values of spectroscopic resolution, absolute sensitivity, the lowest limits of detection, a recovery rate of 90–110% and a coefficient of variation of 3–6% for the quantified elements from mono and multi-element standards. These findings underscore the robust analytical capability of the Total reflection X-ray Fluorescence technique for multi-trace elemental analysis. This research article not only provides practical and straightforward guidelines for handling Total reflection X-ray Fluorescence spectrometer but also confirms the practicality and effectiveness of the sample carriers for rapid and reliable elemental screening applications.

Bioaccessibility, exposure and risk assessment of potentially toxic elements and essential micronutrients in ayurvedic, traditional Chinese and Ghanaian medicines.

Potentially toxic constituents in traditional medicines remain a concern due to health risks posed to consumers. Thirty-six traditional medicines (TM) consisting of 14 Indian Ayurvedic Medicines, 11 Chinese Traditional Medicines and eleven Ghanaian Traditional Medicines were evaluated using Total Reflection X-ray Fluorescence Spectrometer (T-XRF) after microwave assisted acid digestion. Physiologically Based Extraction Test (PBET) was used to obtain bioaccessible elemental concentrations. Merck XVI multi-element standard were used to evaluate the accuracy of the analytical method. The concentrations of the elements were quantified in (mg kg-1): Cr (0.01-698), Mn (0.01-1140), Fe (15-73300), Ni (1-1340), Cu (3-8160), Zn (0.01-224). The greatest bioaccessible concentrations of arsenic was 0.80mgkg-1 and 0.44mgkg-1 in the gastric and intestinal phases respectively. In order to evaluate the human health risks from ingesting these TM, the Acceptable Daily Intake (ADI) was calculated for each medicine based on element-specific bioaccessibility-adjusted concentrations and results compared with the United States Environmental Protection Agency (USEPA) Reference Dose (RfD) limits. The Acceptable Daily Intake (ADI) values for risks were within the USEPA RfD. Hazard quotients (HQ) of TM were < 1, meaning elemental concentrations do not pose non-carcinogenic risks to adult consumers. In summary the methods applied in the study gives a new insight on human health risks of potentially toxic and essential micronutrients elements in TM.

Analysis of Metals Eluted from Stainless Steel in Ultrapure Water Using a Portable Total Reflection X-ray Fluorescence Spectrometer

Analysis of Metals Eluted from Stainless Steel in Ultrapure Water Using a Portable Total Reflection X-ray Fluorescence Spectrometer

Portable Total Reflection X-ray Fluorescence Spectrometer with a Detection Limit in the 100 ng/L Range

Portable Total Reflection X-ray Fluorescence Spectrometer with a Detection Limit in the 100 ng/L Range

Investigating the impact of internal standard heterogeneity on gold quantification with total reflection X‐ray fluorescence: A simulation study

Total reflection X‐ray Fluorescence (TXRF) is a powerful analytical tool with high detection sensitivity that has been applied to a variety of biological samples. While its ability to quantify gold nanoparticles (AuNPs) in cancer cells has been demonstrated, the extension to tissue slices would be of interest. To that end, the preservation of the underlying tissue microstructure requires samples to be measured as microtome slices. In this form, internal standard spiking is warranted. Thus, it is important to examine the impact of sample heterogeneity on the TXRF's quantification accuracy. To address these questions, a TXRF spectrometer along with 5 μm thin heterogeneous and homogeneous samples were modeled using TOPAS. The simulation model generated TXRF spectra which were then analyzed to obtain recovery rates of Au in both sample types. The results showed near 100% recovery regardless of the elemental spatial distribution in the samples. This provides insights into the quantification potential for AuNPs inside tumors that are histologically processed into thin tissue slices. In addition, this simulation toolkit provides the first practical means of modeling TXRF spectroscopy which will hopefully be of use to the TXRF community.

An Evaluation of Total Reflection X-Ray Fluorescence as a Tool for Forensic Discrimination of Single Polyester Fibers.

Total reflection X-ray fluorescence (TXRF) spectrometry was applied to a forensic discrimination of single polyester fibers. In a non-destructive direct measurement of 5 mm long single fibers used for forensic references, trace metallic elements such as Ti, Sb, Ge, Mn, and Co, found in additives and catalyst residues, were detected using a benchtop TXRF spectrometer. The individual elemental compositions of the fibers were identified, and correlations between the compositions and manufacturers were established using principal component analysis (PCA). Black polyester fibers sampled from the car trunk mats were also analyzed. Several fibers were found to contain both Sb and Ge, elements that characterize different polymerization catalysts; this indicates that the fibers were composed of recycled materials. The TXRF and SR-μXRF spectra showed similar patterns for the fiber samples that were analyzed.

Analysis of Single Synthetic Fibers Using a Portable Total Reflection X-ray Fluorescence Spectrometer.

In this study, single synthetic fibers obtained from several textile products were analyzed by a portable total reflection X-ray fluorescence spectrometer. Characteristic elements, which would originate from such materials as catalysts, delustering agents, and dyes used for manufacturing synthetic fibers, were detected from single synthetic fiber samples, and the difference in the types of characteristic elements among the single synthetic fiber samples was observed.

Total reflection X-ray fluorescence analysis of high purity quartz: A bottom-up approach of uncertainty evaluation

High purity quartz was analyzed using Total Reflection X-Ray Fluorescence (TXRF) spectrometry, during our participation in proficiency testing programme. The sample was digested in HF-HNO3 medium and the silica matrix was removed as silicon tetra fluoride by evaporation and repeated treatments with HNO3. Trace metallic impurities viz. K, Ca, Ti and Fe were quantified via the internal standard (using Ga) method in TXRF spectrometry. The z-score, zeta score and quality control sample analysis revealed the accuracy of the present determinations for all the analytes. Combined uncertainty for the measurement was evaluated through the bottom-up approach. Relative sensitivity of the TXRF spectrometer for the analyte with respect to the internal standard was found to hold the highest share of uncertainty. Detection limits for both the process blank and sample solutions were compared. Detection limits in the sample solutions were 1.86, 0.95, 0.94 and 0.30 mg kg−1 for K, Ca, Ti and Fe respectively. These studies brought out the importance of appropriate concentration of standard solutions for calibration and sensitivity measurements of the spectrometer, in addition to the quality of reference standard solution, for ensuring accuracy of the results.

Development of a Portable XRF Spectrometer and Its Application

We have developed 2 kinds of portable XRF spectrometers for on-site analysis. The first is equipped with a monochromator, making it possible to sensitively analyze under a low background. This equipment is used widely in the archaeology field and an industrial field. Recently, we also developed equipment that improved the analysis sensitivity of the light element.Another equipment is a portable total reflection X-ray fluorescence (TXRF) spectrometer. We developed this equipment using polychromatic X-rays from an X-ray source of single-digit Watt. It has an analysis sensitivity of pg order. This equipment is used in the environment field, biological samples and in the analysis of uranium from nuclear power plants. This report, introduces an outline and application examples about 2 kinds of portable XRF spectrometers.

Granular activated charcoal from peanut (Arachis hypogea) shell as a new candidate for stabilization of arsenic in soil

A sandy soil of pH = 5.0 artificially contaminated with 15 mg/kg As in form of arsenate ions [iAs(V)] corresponding to the permissible value in force in Hungary was incubated for 4 weeks after amendment with different peanut shell-derived activated charcoal (AC) materials at an application rate of 2 wt%. Composite formation with silicate materials and adsorption mechanism for As were corroborated by attenuated total-reflection Fourier-transform infrared spectroscopy. Moreover, 0.01 M oxalic acid (OA) was also applied to investigate further enhancement through protonation of iAs(V) and/or AC. Assessment of As stabilization was achieved by a fit-to-purpose BCR sequential soil extraction procedure (extraction of the water-soluble and carbonatic fraction with 0.11 M acetic acid solution and the easily reducible one by 0.5 M hydroxylamine hydrochloride). Arsenic phytoavailability was estimated by leaching with 0.02 M EDTA solution (pH = 4.65). Samples were analyzed by inductively coupled plasma sector field mass spectrometer applying high resolution mode. Total-reflection X-ray fluorescence spectrometer was used to check data accuracy. The largest As stabilization rate (approximately 30%) compared to the reference soil treatment was obtained when granular Florisil®-AC was applied. Stabilization efficiency did not improve by using OA. A 5 wt% AC application rate for the Florisil® composite resulted in a similar As distribution to the 2 wt% one also at a 30 mg/kg iAs(V) dosage. The amounts of immobilized As increased almost proportionally with the higher AC application rate by doubling the iAs(V) dose. Similarly, studies conducted on solutions proved that As adsorption onto ACs was slightly exponential.

Possibility of the total reflection x-ray fluorescence spectrometer for the determination of lead in biological samples

Mongolia has been exposed to extreme draught and dry summer for its historical development due to geographical location, climatic condition, surface characteristics and being subject to vulnerable and dry region in terms of ecological system. Besides it, rapid increase in the minerals production has been causing heavy metal pollution in soil, water and plants. Soil pollution is main parameter of environmental pollution and air and water pollution directly depend on it. Main influencing factor of endemic diseases of livestock is chemical ingredient of soil, water and plant. Due to negligent use and disposal of lead containing sources including acid and alkali batteries with lead conductor, vehicle accumulators in last years, environment has been polluted greatly and it becomes the cause of animal poisoning. Heavy metals are dangerous because of their persistence and toxicity. Soil behaves as a sink of heavy metals by aerial deposition of particles emitted by human activities. The aims of this work were to identify the levels of lead in accumulator processing plant and city areas and animals. We have determined lead level in biological samples /livestock blood/ using total reflection X-ray fluorescence spectrometer and compared the results found by the Lead Care II.&#x0D; Бүрэн ойлтын рентгенфлоуресценцийн спектрометр ашиглан биологийн дээжинд хартугалга тодорхойлох боломж&#x0D; Хураангуй: Монгол орон газар зүйн байршил, уур амьсгалын нөхцөл, газар нутгийн гадаргын хэв шинж,экологийн тогтолцооны хувьд нэн эмзэг, хуурай бүс нутагт хамрагддагийн улмаас түүхэн хөгжлийнхөө турш ган, зуданд нэрвэгдсээр ирсэн байна. Үүний зэрэгцээ манай оронд ашигт малтмалын олборлолт эрс нэмэгдсэнээр хөрс, ус, ургамал хүнд металлаар ихээр бохирдох боллоо. Хөрсний бохирдол нь байгаль, орчны төлөв байдлын гол үзүүлэлт бөгөөд агаар, усны бохирдол үүнээс шууд хамаарна [1]. Мал, амьтны нутгийн орогнол (эндемик) өвчинд гол нөлөөлөх зүйл бол хөрс, ус, ургамлын химийн найрлага юм. Хар тугалган дамжуулагч бүхий хүчлийн болон шүлтийн батарей, автомашины аккуммулятор зэрэг хар тугалга агуулсан эх үүсвэрүүдийг эмх замбараагүй хаясны улмаас байгаль орчин хар тугалгаар ихээр бохирдож мал, амьтны хордох шалтгаан болж байна. Хар тугалгыг мэдрэлийн хор гэж нэрлэдэг бөгөөдөсөлт, тархины хөгжлийг саатуулах аюултай. Иймд бид бүрэн ойлтын рентген флуоресценцийн аргыг ашиглан биологийн дээжинд (малын цусанд) хар тугалганы хэмжээг тодорхойлон, үр дүнг LeadCare II багажийн хэмжилтийн дүнтэй харьцуулав. Бидний хийсэн хэмжилтийн дүнгээс харахад 2 багажийн тоон үзүүлэлт хамаарлын шугаманд ойролцоо гарч байна.&#x0D; Түлхүүр үг: Хүнд метал, үхэр, цус, дээж

Trace determination of uranium preconcentrated using graphene oxide by total reflection X‐ray fluorescence spectrometry

A new method based on dispersive microsolid phase extraction using graphene oxide (GO) as a solid adsorbent and total reflection X‐ray fluorescence (TXRF) spectrometry is proposed for trace determination of uranium. In the developed methodology, a suspension of GO was injected into uranium‐spiked multielement solutions including rubidium; after filtration, the membrane filter with collected GO was placed in a small volume of internal standard acid solution and the eluent containing uranium was deposited onto a fluorine resin‐coated slide glass, which is a disposable sample stage. Using GO was effective for removal of rubidium from the measurement solution to avoid interference between Rb Kα peak and U Lα peak. The high enrichment factor of 150 enables obtaining uranium detection limits of 0.042, 0.087, and 0.12 μg L−1 for ionic strength of 0.01, 0.1, and 1 mol L−1, respectively. Such low detection limits were obtained by using a benchtop TXRF spectrometer with 5‐min measurement. The proposed method is suitable for trace uranium determination in water, including high salinity samples.

Trace Determination of Cyanocobalamin (Vitamin B12) by Analyzing Cobalt Using a Portable Total-Reflection X-ray Fluorescence Spectrometer.

A method is presented for the detection of a trace amount of cyanocobalamin (vitamin B12) using a combination of solid-phase extraction and the measurement of cobalt in vitamin B12 by a portable total-reflection X-ray fluorescence spectrometer. Using this combination, a detection limit of 1 ng/mL was achieved for vitamin B12.

Determination of trace elements in normal and malignant breast tissues of different age group using total reflection X‐ray fluorescence spectrometer

The trace elements in normal and malignant breast tissues of different age groups have been determined using total reflection X‐ray fluorescence (TXRF) spectrometry. The low Z elements are detected using a vacuum chamber of low Z–high Z (WOBISTRAX) TXRF spectrometer and medium and high Z elements using Ital structures TX‐2000 TXRF spectrometers. The trace elements such as Al, P, S, Cl, K, Ca, Ti, Fe, Cu, Zn, Br, Sr, and Y have been detected in normal and malignant breast tissues in the age group 31–40, 41–50, 51–60, and 61–70 years. It is found that the concentration of trace elements such as Al and Ti, Cu and Zn, Ti and Br, and Al and Y are higher in normal breast tissues than in the malignant breast tissues in the samples of age group 31–40, 41–50, 51–60, and 61–70 years, respectively. It is very important to note that the trace element Pb is not observed in the samples of age group 31–40, 41–50, and 51–60, but it has been observed in the samples of age group 61–70 years. Trace elements in normal and malignant tissues measured using TXRF spectrometers. Tissues of different age group have been selected to ascertain the role of trace elements. Trace elements P, S, Cl, K, Ca, Fe, and Sr are found to be higher in malignant tissues. Trace element Pb is found to be higher in malignant tissues in the age group 61–70.

Confocal total reflection X-ray fluorescence technology based on an elliptical monocapillary and a parallel polycapillary X-ray optics

A total reflection X-ray fluorescence (TXRF) spectrometer based on an elliptical monocapillary X-ray lens (MXRL) and a parallel polycapillary X-ray lens (PPXRL) was designed. This TXRF instrument has micro focal spot, low divergence and high intensity of incident X-ray beam. The diameter of the focal spot of MXRL was 16.5 µm, and the divergence of the incident X-ray beam was 3.4 mrad. We applied this TXRF instrument to the micro analysis of a single-layer film containing Ni deposited on a Si substrate by metal vapor vacuum arc ion source.

Total reflection X-ray Fluorescence determination of interfering elements rubidium and uranium by profile fitting

Systematic studies to assess the analytical parameters obtained in the total reflection X-ray fluorescence (TXRF) determinations of interfering elements Rb and U using profile fitting are reported in the present manuscript. The X-ray lines Rb Kα and U Lα having serious spectral interference (ΔE=218eV), have been used as analytical lines. The intensities of these X-ray lines have been assessed using profile fitting. In order to compare the analytical results of Rb determinations in presence of U, with and without U excitation, synchrotron radiation was tuned to energy just above and below the U Labs edge. This approach shall excite both Rb Kα and U Lα simultaneously and Rb Kα selectively. Finally, the samples were also analyzed with a laboratory based TXRF spectrometer. The analytical results obtained in all these conditions were comparable. The authenticity of the results was assessed by analyzing U with respect to Rb in Rb2U(SO4)3, a standard reference material for U. The average precision obtained for TXRF determinations was below 3% (RSD, n=3, 1σ) and the percent deviation of TXRF values from the expected values calculated on the basis of sample preparation was within 3%.

Determination of trace metals in spirits by total reflection X-ray fluorescence spectrometry

Eight spirituous samples were analyzed for trace metal content with Horizon Total Reflection X-Ray Fluorescence (TXRF) Spectrometer. The expected single metal amount is at the ng/g level in a mixed aqueous/organic matrix, thus requiring a sample preparation method capable of achieving suitable limits of detection. On-site enrichment and Atmospheric Pressure-Vapor Phase Decomposition allowed to detect Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Sr and Pb with detection limits ranging from 0.1ng/g to 4.6ng/g. These results highlight how the synergy between instrument and sample preparation strategy may foster the use of TXRF as a fast and reliable technique for the determination of trace elements in spirituous samples, either for quality control or risk assessment purposes.

Elemental analysis of teas, herbs and their infusions by means of total reflection X-ray fluorescence

This work shows that total reflection X-ray fluorescence (TXRF) is a suitable tool for multi-elemental analysis of teas, herbs and their infusion. A low power benchtop TXRF spectrometer was used. Safety of infusion consumption was evaluated. Many commercially available teas,herbs and roots samples were analyzed. Total concentrations of thirteen elements K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Rb, Sr, Ba and Pb as well as their extraction efficiencies into infusion were determined. The content of Pb is highlighted in all teas and herbs, in the concentration range between 0.5 and 4.8 mg/g, but only in infusions of herbs. Chemometry was applied for classification purposes. Elemental daily intakes with respect to infusion drinking was calculated and compared with dietary reference intake values. Results show that TXRF is a fast and simple technique for safety check of tea and herb infusions on a routine basis.

Comprehensive approach to the validation of the standard method for total reflection X-ray fluorescence analysis of water

In this work, we present the validation of the chemical method for total reflection X-ray fluorescence (TXRF) analysis of water, proposed as a standard to the International Standard Organization. The complete experimental procedure to define the linear calibration range, elements sensitivities, limits of detection and quantification, precision and accuracy is presented for a commercial TXRF spectrometer equipped with Mo X-ray tube. Least squares linear regression, including all statistical tests is performed separately for each element of interest to extract sensitivities. Relative sensitivities with respect to Ga, as internal standard, are calculated. Accuracy and precision of the quantification procedure using Ga as internal standard is evaluated with reference water samples. A detailed discussion on the calibration procedure and the limitation of the use of this method for quantitative analysis of water is presented.