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  • 1
    Language: English
    In: Spectrochimica Acta Part B: Atomic Spectroscopy, 2010, Vol.65(6), pp.471-477
    Description: This is the first study applying the technique of cold plasma ashing on polycarbonate filters as a preparative step for subsequent elemental analysis of aerosol particles by Total-Reflection X-ray fluorescence. The procedure has been validated by analyzing blanks of the filter material, chemicals used as additives as well as certified standard reference material. The results showed that cold plasma ashing is superior to conventional digestion methods with regard to the ease of sample preparation and contamination. A PIXE cascade impactor was used to collect size-fractionated aerosol particles in 9 size classes ranging from 16 to 0.06 µm aerodynamic diameter at an urban and a suburban site in Göteborg, Sweden. Filter segments loaded with the aerosol particles were cut out and fixed on Quartz carriers. After adding 10 ng of Ga as internal standard the samples were dried, digested by cold plasma ashing and analyzed by Total-Reflection X-ray fluorescence. The analysis of aerosol particles showed that elemental concentrations at both the urban and the suburban site in Göteborg were low compared to central Europe. More and concurrent sampling of size-fractionated particles is required to identify local sources of trace elements in the urban area of Göteborg.
    Keywords: Elemental Analysis ; Aerosol Particles ; Total Reflection X-Ray Fluorescence ; Cold Plasma Ashing (CPA) ; Polycarbonate Filters ; Chemistry ; Physics
    ISSN: 0584-8547
    E-ISSN: 1873-3565
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  • 2
    Language: English
    In: Environmental Monitoring and Assessment, 2015, Vol.187(7), pp.1-13
    Description: As benthic biofilms mediate essential functions in stream ecosystems (e.g., carbon flux, storage of nutrients and other substances), the element-specific regulation of the biofilm composition is of great interest. We tested whether (1) the elemental composition of biofilms is related to that of the water column and (2) there are different accumulation patterns from the dissolved phase (adsorption) and the particulate phase (incorporation of suspended matter). We analysed biomass parameters, nutrients and metals in biofilms and surface waters at 28 sites within a stream network (Bode catchment, Germany). Algal biomass in biofilms was dominated by diatoms. The P/C ratio in biofilms was positively related to total phosphorus of surface water (and to the proportion of agricultural area in the catchment) indicating phosphorus limitation of biofilms, whereas the N/C ratio was not related to nitrate levels of surface water, and neither the P/C nor the N/C ratio to the concentration of dissolved organic carbon (DOC) of surface water. Biofilms were enriched in metals compared to their concentrations in water. The metals in biofilms were positively related to the concentration of dissolved metals in surface water for iron and strontium (but not for manganese, copper, zinc, arsenic or lead) and to the concentrations of particle-associated metals of surface waters for strontium and lead. Manganese and arsenic were the metals with a negative effect on the biomasses of biofilm diatoms and cyanobacteria. Overall, we observed element-specific accumulation patterns in biofilms with selected elements being related to the water column while others were probably subject to biofilm-internal processes.
    Keywords: Nutrients ; Stoichiometry ; Heavy metals ; Total reflection X-ray fluorescence spectrometry (TXRF) ; Stream biofilms ; River Bode
    ISSN: 0167-6369
    E-ISSN: 1573-2959
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  • 3
    Language: English
    In: Environmental Monitoring and Assessment, 2015, Vol.187(7), p.1(13)
    Description: Byline: Norbert Kamjunke (1,2), Margarete Mages (1), Olaf Buttner (3), Hanna Marcus (1), Markus Weitere (1) Keywords: Nutrients; Stoichiometry; Heavy metals; Total reflection X-ray fluorescence spectrometry (TXRF); Stream biofilms; River Bode Abstract: As benthic biofilms mediate essential functions in stream ecosystems (e.g., carbon flux, storage of nutrients and other substances), the element-specific regulation of the biofilm composition is of great interest. We tested whether (1) the elemental composition of biofilms is related to that of the water column and (2) there are different accumulation patterns from the dissolved phase (adsorption) and the particulate phase (incorporation of suspended matter). We analysed biomass parameters, nutrients and metals in biofilms and surface waters at 28 sites within a stream network (Bode catchment, Germany). Algal biomass in biofilms was dominated by diatoms. The P/C ratio in biofilms was positively related to total phosphorus of surface water (and to the proportion of agricultural area in the catchment) indicating phosphorus limitation of biofilms, whereas the N/C ratio was not related to nitrate levels of surface water, and neither the P/C nor the N/C ratio to the concentration of dissolved organic carbon (DOC) of surface water. Biofilms were enriched in metals compared to their concentrations in water. The metals in biofilms were positively related to the concentration of dissolved metals in surface water for iron and strontium (but not for manganese, copper, zinc, arsenic or lead) and to the concentrations of particle-associated metals of surface waters for strontium and lead. Manganese and arsenic were the metals with a negative effect on the biomasses of biofilm diatoms and cyanobacteria. Overall, we observed element-specific accumulation patterns in biofilms with selected elements being related to the water column while others were probably subject to biofilm-internal processes. Author Affiliation: (1) Department of River Ecology, Helmholtz-Centre for Environmental Research-UFZ, Bruckstra[sz]e 3a, 39114, Magdeburg, Germany (2) Department of Lake Research, Helmholtz-Centre for Environmental Research-UFZ, Bruckstra[sz]e 3a, 39114, Magdeburg, Germany (3) Department of Aquatic Ecosystem Analysis and Management, Helmholtz-Centre for Environmental Research-UFZ, Bruckstra[sz]e 3a, 39114, Magdeburg, Germany Article History: Registration Date: 03/06/2015 Received Date: 09/05/2014 Accepted Date: 03/06/2015 Online Date: 16/06/2015 Article note: Electronic supplementary material The online version of this article (doi: 10.1007/s10661-015-4664-6) contains supplementary material, which is available to authorized users.
    Keywords: X-Ray Spectroscopy – Analysis ; Fluorescence – Analysis ; Heavy Metals – Analysis ; Water Resources – Analysis ; Adsorption – Analysis ; Ecosystems – Analysis ; Arsenic – Analysis
    ISSN: 0167-6369
    Source: Cengage Learning, Inc.
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  • 4
    Language: English
    In: 2015
    Keywords: Zinc ; In Vitro Studies ; In Vitro Culture ; Biofilm ; Freshwater ; Fluorescence ; Copper ; Watersheds ; Adsorbents ; Laboratory Experimentation ; Rivers ; Cyanides ; Heavy Metals ; X-Radiation
    Source: AGRIS (Food and Agriculture Organization of the United Nations)
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  • 5
    Language: English
    In: Spectrochimica Acta Part B: Atomic Spectroscopy, 2006, Vol.61(10), pp.1146-1152
    Description: Human impacts like mining activities lead to higher element concentration in surface waters. For different pollution levels, the consequences for aquatic organisms are not yet investigated in detail. Therefore, the aim of this investigation is to determine the influence of mining affected surface waters on biofilms. Elements like heavy metals can be absorbed on cell walls and on polymeric substances or enter the cytoplasm of the cells. Thus, they are important for the optimization of industrial biotechnological processes and the environmental biotechnology. Beyond this, biofilms can also play an important role in wastewater treatment processes and serve as bioindicators in the aquatic environment. The presented total reflection X-ray fluorescence spectroscopic investigation was performed to compare the element accumulation behavior of biofilms grown on natural or on artificial materials of drainage water affected by former copper mining activities. A high salt and heavy metal pollution is characteristic for the drainage water. For an assessment of these results, samples from stream Schlenze upstream the confluence with the drainage water, a small tributary of the Saale River in central Germany, were analyzed, too.
    Keywords: Heavy Metals ; Element Determination ; Element Accumulation ; Biofilms ; Mining ; Txrf ; Chemistry ; Physics
    ISSN: 0584-8547
    E-ISSN: 1873-3565
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  • 6
    Language: English
    In: Spectrochimica Acta Part B: Atomic Spectroscopy, 2009, Vol.64(4), pp.354-356
    Description: In clinical service laboratories, one of the most common analytical tasks with regard to inorganic traces is the determination of the nutrition-relevant elements Fe, Cu, Zn, and Se. Because of the high numbers of samples and the commercial character of these analyses, a time-consuming sample preparation must be avoided. In this presentation, the results of total reflection X-ray fluorescence measurements with a low-power system and different sample preparation procedures are compared with those derived from analysis with common methods like Atomic Absorption Spectroscopy (AAS) and Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). The results of these investigations indicate that the optimal total reflection X-ray fluorescence analysis of the nutrition-relevant elements Fe, Cu, Zn, and Se can be performed by preparing whole blood and serum samples after dilution with ultrapure water and transferring 10 μl of internally standardized sample to an unsiliconized quartz glass sample carrier with subsequent drying in a laboratory oven. Suitable measurement time was found to be 600 s. The enhanced sample preparation by means of microwave or open digestion, in parts combined with cold plasma ashing, led to an improvement of detection limits by a factor of 2 for serum samples while for whole blood samples an improvement was only observed for samples prepared by means of microwave digestion. As the matrix elements P, S, Cl, and for whole blood Fe have a major influence on the detection limits, most probably a further enhancement of analytical quality requires the removal of the organic matrix. However, for the routine analysis of the nutrition-relevant elements, the dilution preparation was found to be sufficient.
    Keywords: Txrf ; Blood ; Serum ; Nutrition ; Trace Elements ; Chemistry ; Physics
    ISSN: 0584-8547
    E-ISSN: 1873-3565
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  • 7
    Language: English
    In: Analytical and Bioanalytical Chemistry, 2004, Vol.378(4), pp.1095-1101
    Description: The aim of this work was to investigate the heavy metal accumulation by natural biofilms living in the catchment area of the Tisza river in Hungary, as well as in biofilms cultivated in vitro. Laboratory tests have demonstrated that metals can be adsorbed on biofilms, depending on their concentration and on the availability of free sorptive places. Biofilms were cultivated in vitro in natural freshwater from the Saale river, Germany. After reaching the plateau phase, Cu was added to reach a concentration of 100 µg/L. An increase of its mass fraction in the biofilm was observed, which caused the decrease of the concentration in the water phase. Unfortunately, the reactor wall was also found to act as adsorbent for Cu. More detailed results of our in vitro experiments will be published in a forthcoming paper. Naturally grown biofilm samples from exposed as well as background places at the Hungarian rivers Szamos and Tisza were collected in 2000 and 2002 after the cyanide spill, and analysed using total reflection X-ray fluorescence analysis (TXRF). Metal mass fraction differences as high as two orders of magnitude were found between polluted and unpolluted (background) sampling points. Extremely high concentration values, e.g . 5600 µg/g Zn in biofilm, were found at highly polluted sampling points. This means an enrichment factor of ca. 10,000 compared to the water phase.
    Keywords: Total reflection X-ray fluorescence ; Trace element accumulation ; Biofilms ; Tisza river ; Trace element determination ; Rotating annular reactor
    ISSN: 1618-2642
    E-ISSN: 1618-2650
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  • 8
    Language: English
    In: Microchimica Acta, 2006, Vol.154(3), pp.261-268
    Description: The trace element content of individual copepod specimens and of the Brazilian water weed ( Egeria densa ) from a metal-contaminated wetland in Southern Chile were determined using total reflection X-ray fluorescence spectrometry. Sampling of the water and the organisms was carried out at three sampling sites during 2004. Enhanced concentrations of dissolved Fe and Mn were found in the column water and in the pore water. The Fe content in the benthic copepods was significantly elevated compared to other aquatic organisms from different Chilean lakes. Regarding E. densa , healthy (green coloured) plants showed mass fractions of Fe, Mn, Ni, Cu and Zn which were typical for uncontaminated systems. In contrast, damaged (brownish coloured) plants exhibited very high Fe and Mn concentrations indicative of contamination or processes which changed the element load from the environment to the plant.
    Keywords: Key words: Bioaccumulation; cyclopods; TXRF; ; heavy metal uptake.
    ISSN: 0026-3672
    E-ISSN: 1436-5073
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  • 9
    Language: English
    In: Analytical and Bioanalytical Chemistry, 2004, Vol.378(4), pp.1088-1094
    Description: First results are described from the application of a recently developed dry method for determination of elements in single specimens of freshwater microcrustaceans, using total reflection X-ray fluorescence spectrometry (TXRF). This method is a powerful, non-destructive technique for quantifying the trace element content of minute biological samples with a dry weight of 3–50 μg. Three different freshwater microcrustaceans were sampled, from the natural, uncontaminated Lake Laja and from the artificial Rapel reservoir which is slightly contaminated by drainage water from a copper mine. Single specimens of Daphnia pulex , Bosmina chilensis , and Ceriodaphnia dubia were prepared using a modification of the dry method and measured by TXRF. The results showed that both As, Mn, Fe, Ni, Zn, and Cu content and the bioaccumulation of these metals were usually significantly different between the microcrustaceans from the two lakes. The largest difference was found for Cu which was eight times more concentrated in the two microcrustaceans from Rapel reservoir than it was in D. pulex from Lake Laja.
    Keywords: Trace elements ; Zooplankton ; Total reflection X-ray fluorescence ; Bioaccumulation ; Metals
    ISSN: 1618-2642
    E-ISSN: 1618-2650
    Source: Springer Science & Business Media B.V.
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  • 10
    Language: English
    In: Analytical and bioanalytical chemistry, February 2004, Vol.378(4), pp.1088-94
    Description: First results are described from the application of a recently developed dry method for determination of elements in single specimens of freshwater microcrustaceans, using total reflection X-ray fluorescence spectrometry (TXRF). This method is a powerful, non-destructive technique for quantifying the trace element content of minute biological samples with a dry weight of 3-50 microg. Three different freshwater microcrustaceans were sampled, from the natural, uncontaminated Lake Laja and from the artificial Rapel reservoir which is slightly contaminated by drainage water from a copper mine. Single specimens of Daphnia pulex, Bosmina chilensis, and Ceriodaphnia dubia were prepared using a modification of the dry method and measured by TXRF. The results showed that both As, Mn, Fe, Ni, Zn, and Cu content and the bioaccumulation of these metals were usually significantly different between the microcrustaceans from the two lakes. The largest difference was found for Cu which was eight times more concentrated in the two microcrustaceans from Rapel reservoir than it was in D. pulex from Lake Laja.
    Keywords: Crustacea -- Chemistry ; Environmental Monitoring -- Methods ; Fresh Water -- Chemistry ; Trace Elements -- Analysis ; Zooplankton -- Chemistry
    ISSN: 1618-2642
    E-ISSN: 16182650
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