Publications in Scientific Journals:

F. Meirer, G. Pepponi, C. Streli, P. Wobrauschek, V.G. Mihucz, G. Zaray, V. Czech, J.A. Broekaert, U. Fittschen, G. Falkenberg:
"Application of synchrotron-radiation-induced TXRF-XANES for arsenic speciation in cucumber (Cucumis sativus L.) xylem sap";
X-Ray Spectrometry, 36 (2007), 408 - 412.

English abstract:
Synchrotron-radiation-induced total reflection x-ray fluorescence (SR-TXRF) analysis was used for x-ray
absorption near edge structure (XANES) measurements for the speciation of arsenic in cucumber (Cucumis
sativus L.) xylem sap. The objective of the presented work was to exploit the advantages of the TXRF
geometry for XANES analysis. Measurements were accomplished at the bending magnet beamline L of
HASYLAB, Hamburg, Germany, using a Si(111) double crystal monochromator and a silicon drift detector
(SDD). Experiments were performed by growing cucumber plants in hydroponics containing arsenite
[As(III)] or arsenate [As(V)] in order to identify the arsenic species of the collected xylem saps by K-edge
SR-TXRF XANES. Cucumber xylem saps, as well as nutrient solutions containing arsenic in the two
above-mentioned species, were analyzed and compared with arsenate and arsenite standard solutions.
Arsenic speciation in xylem sap down to 30 ng/ml (30 ppb) was achieved, and no alteration of the oxidation
state was observed during the measurements. Analysis of xylem saps showed that As(V) taken up from
the nutrient solution was reduced to As(III). As(III) contained in the nutrient solutions was found to be
partially oxidized to As(V). These results confirmed the preliminary measurements obtained with flow
injection analysis (FIA) and high-performance liquid chromatography-high resolution inductively coupled
plasma mass spectrometry (HPLC-HR-ICP-MS) and showed the competitive capability of SR-TXRFXANES
analysis for this application.

Created from the Publication Database of the Vienna University of Technology.