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Die Mitte des 16. Jahrhunderts gegründete Dresdener Goldschmiedeinnung, geriet im 19. Jahrhundert in wirtschaftliche Schwierigkeiten, was letztendlich zu ihrer Auflösung führte. Im Zuge dessen wurde 1872 auch der historische Innungspokal für 80 Taler an das Grüne Gewölbe in Dresden verkauft. Sowohl das Empfehlungsschreiben des damaligen Direktors als auch die Zustimmung zum zügigen Ankauf dürften Beleg dafür sein, dass man damals der festen Überzeugung war, ein etwa 250 Jahre altes, authentisches Silbergefäß erworben zu haben. Die aktuelle kunstwissenschaftliche Begutachtung des Innungspokals lässt begründete Fragen zum Alter und zur Originalität des Objektes, welches heute in der Sammlung des Grünen Gewölbes präsentiert wird, aufkommen. Die kunst-wissenschaftliche und kunsttechnologische Expertise reicht hier allein ftir eine gesicherte Altersbestimmung nicht aus und soll deshalb durch naturwissenschaftliche Untersuchungen zur Materialzusammensetzung unterstützt werden.
Wilson´s disease, a rare genetic disorder of the copper metabolism, causes the copper accumulation in various organs, leading to manifold hepatic, neurological and psychiatric symptoms. To study the elemental distribution, human Wilson´s disease liver samples were analyzed by means of LA-ICP-MS. Results demonstrated an inhomogeneous copper and iron distribution in human liver with hotspots of very high intensities. Both elements were quantified by an external calibration using matrix-matched standards made of gelatin, showing concentrations up to several thousand micrograms per gram. Additionally, results were validated by means of synchrotron radiation based μXRF at the BAMline at BESSYII (Helmholtz-Zentrum Berlin).
Wilson´s disease (WD) is a rare genetic disorder of the copper metabolism, causing the accumulation of copper in different organs, including the liver, the central nervous system and cornea. This way, WD initiates manifold hepatic, neurological or psychiatric symptoms. To learn about the elemental distribution and present species in WD, liver samples were analyzed by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), micro X-ray fluorescence (μXRF) and X-ray absorption near edge structure spectroscopy (XANES).
Within this work, LA-ICP-MS was applied to study the distribution of copper and iron in human liver samples, which were collected by a liver biopsy of WD and control patients within a medical investigation. The analysis by LA-ICP-MS was performed with a 213 nm Nd:YAG laser using a spatial resolution of 10 μm and a scan rate of 20 μm/s. In a next step, copper and iron were quantified by LA-ICP-MS using homemade matrix-matched standards made of gelatin. Results showed an inhomogeneous copper and iron distribution in human liver with hotspots up to several thousand micrograms per gram liver within the hepatocytes.
Additionally, results for the elemental distribution in WD were validated by means of synchrotron radiation-based μXRF with a beam size of 4 μm at the BAMline at BESSYII (Helmholtz-Zentrum Berlin). Furthermore, XANES was performed to identify the present oxidation states of copper in WD, indicating a mixture of copper(I) and copper(II) within the liver tissue.
In the contemporary medicine, rhodanine staining is routinely used to determine the copper distribution in liver tissues. Nevertheless, this method does not provide results with a high sensitivity in comparison to LA-ICP-MS. Therefore, the presented LA-ICP-MS method offers a new possible diagnostic tool. These results may also contribute to a better understanding of Wilson´s disease and its development.
The gold finds from Bernstorf, in the Freising district of Bavaria, were discovered in 1998, in the area of a Bronze Age settlement. First analyses with X-ray fluorescence (XRF) revealed gold of an unusually high purity grade, which was explained by using cementation techniques.
A newer analysis with laser ablation inductively coupled plasma mass spectrometry (LA–ICP–MS) indicated an even higher purity. These analytical results were the starting point of an ongoing discussion. The amount and type of the detected contaminants were highly controversial and led to contradictory interpretations.
We reanalysed 11 gold samples with synchrotron radiation induced X-ray fluorescence (SRXRF) at the BAMline at BESSY-II. To reach the desired detection limits a thorough analysis with three different excitation energies and detection conditions were applied to confirm or disprove the previous results.
In this contribution we will get into the details for the need of the different measurement conditions and the virtues of the use of synchrotron radiation. The use and effectiveness of cementation techniques will be addressed. Finally we will present the achieved results and their impact on the discussion.
The BAMline at the synchrotron BESSY II in Berlin supplies users with up to date analytical x-ray methods for the energy range between 5 and 50 keV. Additional to XRF with micron Resolution it provides amongst other things the possibility to use TXRF and XANES. Especially the use of
the so-called Color X-Ray Camera (CXC) opens the possibility to use new and effective detection schemes, which allow to measure simultaneously distributions of elements or Absorption spectra in a motionless mode.
In this talk the analytical possibilities at the BAMline for samples with biological Background will be introduced. The available methods will be presented and discussed for various examples.
A perspective for the future use for XANES in grazing emission and TXRF geometries for plant materials will be given.
Die Eigenschaften und die Verlässlichkeit von Materialien jeglicher Art sind seit jeher die Grundlagen der Technik einer Gesellschaft. Tiefgreifende Kenntnisse über sie sind deshalb eine Voraussetzung um neue Produkte zu entwickeln, Verlässlichkeit zu gewährleisten, oder aber auch, wie in der Archäometrie, Kenntnisse über die Vergangenheit zu gewinnen. Ein Schlüssel zum Verständnis ist das Wissen über die chemische Zusammensetzung und die Struktur von Materialien Die Analyse mit Synchrotronstrahlung bietet hierfür herausragende Werkzeuge an, die zerstörungsfrei und hochsensitiv sind. Mit Röntgenfluoreszenzanalyse kann die elementare Zusammensetzung in winzigen Proben bis auf μg/g bestimmt werden. Anwendungsbeispiele aus verschiedenen Themengebieten, aber besonders von archäologischen Fragestellungen wie z.B. dem Goldfund von Bernstorf werden im Vortrag vorgestellt.
News from the BAMline
(2017)