Total reflection X-ray fluorescence analysis of elemental composition of herbal infusions and teas.

BACKGROUND: The elemental composition of herbal infusions and teas has not been sufficiently investigated. It could potentially be used for defining fingerprints for individual herbal / tea infusions, differentiation of botanical families, detecting the influence of packaging, and other purposes. The objective of this study was to determine the elemental composition, including the trace element content, of various herbal infusions and teas by means of total reflection X-ray fluorescence analysis (TXRF), with a chemometrics approach using principal component analysis (PCA). RESULTS: This study determined the elemental composition of various herbal infusions and teas, including trace elements, using total reflection X-ray fluorescence (TXRF). The methodology for the sample preparation was established, including the multiple-steepings procedure for the two tea samples (Oolong and Pu-erh). Data from 29 samples were collected. We hypothesized that the elemental content of infusions could reflect certain features, such as the influence of processing and the type of tea. CONCLUSION: A chemometric approach (PCA) was applied, and differences between teas and herbal infusions were found. This was further corroborated by explicit differentiation of one botanical family, Theaceae. The influence of packaging (tea bags) on herbal material was identified. The three types of tea (Camellia sinensis) appeared to be separated with PCA, and elemental concentrations in Pu-erh changed with multiple steepings.

Detection and imaging of gadolinium accumulation in human bone tissue by micro- and submicro-XRF.

Gadolinium-based contrast agents (GBCAs) are frequently used in patients undergoing magnetic resonance imaging. In GBCAs gadolinium (Gd) is present in a bound chelated form. Gadolinium is a rare-earth element, which is normally not present in human body. Though the blood elimination half-life of contrast agents is about 90 minutes, recent studies demonstrated that some tissues retain gadolinium, which might further pose a health threat due to toxic effects of free gadolinium. It is known that the bone tissue can serve as a gadolinium depot, but so far only bulk measurements were performed. Here we present a summary of experiments in which for the first time we mapped gadolinium in bone biopsy from a male patient with idiopathic osteoporosis (without indication of renal impairment), who received MRI 8 months prior to biopsy. In our studies performed by means of synchrotron radiation induced micro- and submicro-X-ray fluorescence spectroscopy (SR-XRF), gadolinium was detected in human cortical bone tissue. The distribution of gadolinium displays a specific accumulation pattern. Correlation of elemental maps obtained at ANKA synchrotron with qBEI images (quantitative backscattered electron imaging) allowed assignment of Gd structures to the histological bone structures. Follow-up beamtimes at ESRF and Diamond Light Source using submicro-SR-XRF allowed resolving thin Gd structures in cortical bone, as well as correlating them with calcium and zinc.

Increased zinc accumulation in mineralized osteosarcoma tissue measured by confocal synchrotron radiation micro X-ray fluorescence analysis.

Abnormal tissue levels of certain trace elements such as zinc (Zn) were reported in various types of cancer. Little is known about the role of Zn in osteosarcoma. Using confocal synchrotron radiation micro X-ray fluorescence analysis, we characterized the spatial distribution of Zn in high-grade sclerosing osteosarcoma of nine patients (four women/five men; seven knee/one humerus/one femur) following chemotherapy and wide surgical resection. Levels were compared with adjacent normal tissue. Quantitative backscattered electron imaging as well as histological examinations was also performed. On average, the ratio of medians of Zn count rates (normalized to calcium) in mineralized tumor tissue was about six times higher than in normal tissue. There was no difference in Zn levels between tumor fraction areas with a low fraction and a high fraction of mineralized tissue, which were clearly depicted using quantitative backscattered electron imaging. Moreover, we found no correlation between the Zn values and the type of tumor regression according to the Salzer-Kuntschik grading. The underlying mechanism of Zn accumulation remains unclear. Given the emerging data on the role of trace elements in other types of cancer, our novel results warrant further studies on the role of trace elements in bone cancer. Copyright © 2016 The Authors. X-Ray Spectrometry published by John Wiley & Sons Ltd.

µXRF Elemental Mapping of Bioresorbable Magnesium-Based Implants in Bone.

This study investigated the distribution of the elemental constituents of Mg-based implants at various stages of the degradation process in surrounding bone tissue, with a focus on magnesium (Mg), as the main component of the alloy, and yttrium (Y), due to its potential adverse health effects. The measurements were performed on the implant-bearing thin sections of rat bone in a time series of implant degradation between one and 18 months. Micro X-ray fluorescence analysis (µXRF) with a special spectrometer meeting the requirements for the measurements of low-Z elements was used. It was found that the migration and accumulation behaviour of implant degradation products is element-specific. A sharp decrease in Mg was observed in the immediate vicinity of the interface and no specific accumulation or aggregation of Mg in the adjacent bone tissue was detected. By contrast, Y was found to migrate further into the bone over time and to remain in the tissue even after the complete degradation of the implant. Although the nature of Y accumulations must still be clarified, its potential health impact should be considered.