TY - JOUR A1 - Schneider, Rudolf A1 - Fernandez, L. A1 - Borzecka, W. A1 - Lin, Z. A1 - Huvaere, K. A1 - Esteves, V. I. A1 - Cunha, A. A1 - Tome, J. P. C. T1 - Nanomagnet-photosensitizer hybrid materials for the degradation of 17 beta-estradiol in batch and flow modes N2 - The preparation of porphyrins and phthalocyanines covalently attached onto nanostructured magnetic supports consisting of magnetite nanoparticles coated with an amorphous silica shell is reported. The easy recovery of these heterogeneous photocatalysts, just by applying an external magnetic field, allows their reuse in multiple treatment cycles. The photocatalytic activity of the non-immobilized photosensitizers and the obtained hybrid materials was evaluated in the degradation of 17 beta-estradiol, as a model organic pollutant present in water, using batch and flow mode treatment systems, assisted by visible light radiation (4 mW cm(-2)). The flow mode system potentiated the photocatalytic capacity of these novel hybrid materials. In order to improve the process, further studies based on different photocatalyst concentration and pH conditions were performed. Reuse capacity of these materials was investigated upon three photocatalytic cycles. KW - Photodegradation KW - 17 beta-Estradiol KW - Porphyrin PY - 2017 DO - https://doi.org/10.1016/j.dyepig.2017.04.010 SN - 0143-7208 VL - 142 SP - 535 EP - 543 PB - Elsevier Ltd. AN - OPUS4-43308 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Moraleja, I. A1 - Mena, M. L. A1 - Lázaro, A. A1 - Neumann, B. A1 - Tejedor, A. A1 - Jakubowski, Norbert A1 - Gómez-Gómez, M. M. A1 - Esteban-Fernández, D. T1 - An approach for quantification of platinum distribution in tissues by LA-ICP-MS imaging using isotope dilution analysis N2 - Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been revealed as a convenient technique for trace elemental imaging in tissue sections, providing elemental 2D distribution at a quantitative level. For quantification purposes, in the last years several approaches have been proposed in the literature such as the use of CRMs or matrix matched standards. The use of Isotope Dilution (ID) for quantification by LA-ICP-MS has been also described, being mainly useful for bulk analysis but not feasible for spatial measurements so far. In this work, a quantification method based on ID analysis was developed by printing isotope-enriched inks onto kidney slices from rats treated with antitumoral Pt-based drugs using a commercial ink-jet device, in order to perform an elemental quantification in different areas from bio-images. For the ID experiments ¹⁹⁴Pt enriched platinum was used. The methodology was validated by deposition of natural Pt standard droplets with a known amount of Pt onto the surface of a control tissue, where could be quantified even 50 pg of Pt, with recoveries higher than 90%. The amount of Pt present in the whole kidney slices was quantified for cisplatin, carboplatin and oxaliplatin-treated rats. The results obtained were in accordance with those previously reported. The amount of Pt distributed between the medullar and cortical areas was also quantified, observing different behavior for the three drugs. KW - Isotopic dilution KW - LA-ICP-MS KW - Quantification KW - Imaging KW - Kidney KW - Pt-based drugs PY - 2018 DO - https://doi.org/10.1016/j.talanta.2017.09.031 SN - 0039-9140 VL - 178 SP - 166 EP - 171 PB - Elsevier AN - OPUS4-43627 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fernández, L. A1 - Lin, Z. A1 - Schneider, Rudolf A1 - Esteves, V. I. A1 - Cunha, Â. A1 - Tomé, J. P. C. T1 - Antimicrobial Photodynamic Activity of Cationic Nanoparticles Decorated with Glycosylated Photosensitizers for Water Disinfection N2 - The antimicrobial photodynamic approach has been demonstrated as an efficient and sustainable process for the eradication of microbial pathogens. In this work, silica-coated Magnetite nanoparticles (NPs) were used as carriers of glycosylated porphyrins and phthalocyanines. Their subsequent cationization resulted in the production of stable antimicrobial photosensitizing materials, effective against E. coli. Suspensions of the photocatalysts in water present bimodal size distributions formed by big clusters and small NPs with hydrodynamic diameters between 8 and 38 nm. The presence of small NPs in the suspensions is related to an effective photodynamic inactivation (PDI) of E. coli cells. Glycosylation of the PS showed a positive effect on the PDI performance, which could be related to a higher accumulation of the photocatalyst over the bacterial cell membrane. In addition, these biocidal agents proved to be photostable and their photoactive performance decreased only between 23% and 28% upon 5 PDI cycles, mostly because of the loss of material between cycles, which makes them promising materials for water disinfection purposes. KW - Photodynamische Inaktivierung KW - E. coli KW - Photokatalyse KW - Bakterien KW - Nanopartikel KW - Photosensibilisator KW - Porphyrin KW - Phthalocyanin PY - 2018 DO - https://doi.org/10.1002/cptc.201700169 SN - 2367-0932 VL - 2 IS - 7 SP - 596 EP - 605 PB - Wiley VHC CY - Weinheim AN - OPUS4-45684 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stuckert, J. A1 - Birchley, J. A1 - Große, M. A1 - Fernandez-Moguel, L. A1 - Onel, Yener A1 - Rössger, C. A1 - Steinbrück, M. T1 - The Quench-Debris test - Experimental results and modeling N2 - In the framework of the SARNET-2 WP5.1 the QUENCH-DEBRIS test was conducted as the 17th severe accident test using the QUENCH facility at KIT to investigate the formation and coolability of a prototypic debris bed. The test scenario was defined by pre-test calculations using the MELCOR code. This code was used also for post-test analysis. The test bundle with length of about 2 m contains the hafnium shroud tube and 12 heated peripheral rods with claddings made of hafnium. Hafnium was chosen because of its much higher melting temperature and the about one order of magnitude lower oxidation rate compared to zirconium. The claddings of the inner nine rods were made from Zry-4. They were filled with pre-fragmented zirconia pellets. The test started with an oxidation phase of 20 h at peek cladding temperature about 1800 K to reach complete oxidation of the Zry-4 claddings over a height of 500 mm. The temperatures expected from the pre-test simulation fitted well the experimentally observed evolution of the bundle conditions. The possibly surviving inner Zry-4 claddings were destroyed by the application of an axial mechanical force resulting in material relocation and formation of a heterogeneous debris bed consisting of segmented pellets and larger cladding tube fragments at the grid spacer 2 (350 mm elevation) and in a smaller amount at grid spacer 3 (1050 mm elevation). The so destroyed bundle was quenched with 10 g/s water. The evaporation rate generally showed an increasing trend during the reflood, except at the time of water penetration through the debris bed at spacer 2 when stagnation was observed. All peripheral hafnium claddings survived the whole test. During the oxidation phase about 100 g hydrogen was released. The time dependence of the hydrogen release predicted in the pre-test calculations fits well the measured one. The post-test examinations comprise videoscope inspections, high energy X-ray-tomography and metallographic investigations of the debris bed. T2 - ERMSAR-2013 - 6th European review meeeting on severe accident research CY - Avignon, France DA - 02.10.2013 KW - Hochenergie-Computertomographie KW - Nukleare Sicherheitsforschung PY - 2013 SP - 1 EP - 13 (Paper 2.6) AN - OPUS4-29467 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cruz-Alonso, M. A1 - Fernandez, B. A1 - Álvarez, L. A1 - González-Iglesias, H. A1 - Traub, Heike A1 - Jakubowski, Norbert A1 - Pereiro, R. T1 - Bioimaging of metallothioneins in ocular tissue sections by laser ablation-ICP-MS using bioconjugated gold nanoclusters as specific tags N2 - An immunohistochemical method is described to visualize the distribution of metallothioneins 1/2 (MT 1/2) and metallothionein 3 (MT 3) in human ocular tissue. It is making use of (a) antibodies conjugated to gold nanoclusters (AuNCs) acting as labels, and (b) laser ablation (LA) coupled to inductively coupled plasma – mass spectrometry (ICP-MS).Water-soluble fluorescent AuNCs (with an average size of 2.7 nm) were synthesized and then conjugated to antibody by carbodiimide coupling. The surface of the modified AuNCs was then blocked with hydroxylamine to avoid nonspecific interactions with biological tissue. Immunoassays for MT 1/2 and MT 3 in ocular tissue sections (5 μm thick) from two post mortem human donors were performed. Imaging studies were then performed by fluorescence using confocal microscopy, and LA-ICP-MS was performed in the retina to measure the signal for gold. Signal amplification by the >500 gold atoms in each nanocluster allowed the antigens (MT 1/2 and MT 3) to be imaged by LA-ICP-MS using a laser spot size as small as 4 μm. The image patterns found in retina are in good agreement with those obtained by conventional fluorescence immunohistochemistry which was used as an established reference method. KW - Metal nanoclusters KW - Fluorescence KW - Protein imaging KW - Thin tissue sections KW - Immunohistochemistry KW - Bioconjugation KW - Carbodiimide crosslinking KW - Laser ablation KW - Mass spectrometry PY - 2018 DO - https://doi.org/10.1007/s00604-017-2597-1 VL - 185 IS - 1 SP - 1 EP - 9 PB - Springer AN - OPUS4-44022 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cruz-Alonso, M. A1 - Fernandez, B. A1 - Alvarez, L. A1 - Gonzalez-Iglesias, H. A1 - Traub, Heike A1 - Jakubowski, Norbert A1 - Pereiro, R. T1 - Bioimaging of metallothioneins in ocular tissue sections by laser ablation-ICP-MS using bioconjugated gold nanoclusters as specific tags N2 - An immunohistochemical method is described to visualize the distribution of metallothioneins 1/2 (MT 1/2) and metallothionein 3 (MT 3) in human ocular tissue. It is making use of (a) antibodies conjugated to gold nanoclusters (AuNCs) acting as labels, and (b) laser ablation (LA) coupled to inductively coupled plasma – mass spectrometry (ICP-MS). Water-soluble fluorescent AuNCs (with an average size of 2.7 nm) were synthesized and then conjugated to antibody by carbodiimide coupling. The surface of the modified AuNCs was then blocked with hydroxylamine to avoid nonspecific interactions with biological tissue. Immunoassays for MT 1/2 and MT 3 in ocular tissue sections (5 μm thick) from two post mortem human donors were performed. Imaging studies were then performed by fluorescence using confocal microscopy, and LA-ICP-MS was performed in the retina to measure the signal for gold. Signal amplification by the >500 gold atoms in each nanocluster allowed the antigens (MT 1/2 and MT 3) to be imaged by LA-ICP-MS using a laser spot size as small as 4 μm. The image patterns found in retina are in good agreement with those obtained by conventional fluorescence immunohistochemistry which was used as an established reference method. KW - Nanocluster KW - Immunohistochemistry KW - Laser ablation KW - ICP-MS KW - Fluorescence KW - Bioimaging PY - 2018 DO - https://doi.org/10.1007/s00604-017-2597-1 SN - 1436-5073 SN - 0026-3672 VL - 185 IS - 1 SP - 64 EP - 72 PB - Springer CY - Vienna AN - OPUS4-44637 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Garcia-Fernandez, J. A1 - Turiel, D. A1 - Bettmer, J. A1 - Jakubowski, Norbert A1 - Panne, Ulrich A1 - Rivas Garcia, L. A1 - Llopis, J. A1 - Sanchez-Gonzalez, C. A1 - Montes-Bayon, M. T1 - In vitro and in situ experiments to evaluate the biodistribution and cellular toxicity of ultrasmall iron oxide nanoparticles potentially used as oral iron supplements N2 - Well-absorbed iron-based nanoparticulated materials are a promise for the oral management of iron deficient anemia. In this work, a battery of in vitro and in situ experiments are combined for the evaluation of the uptake, distribution and toxicity of new synthesized ultrasmall (4 nm core) Fe2O3 nanoparticles coated with tartaric/adipic acid with potential to be used as oral Fe supplements. First, the in vitro simulated gastric acid solubility studies by TEM and HPLC-ICP-MS reveal a partial reduction of the core size of about 40% after 90 min at pH3. Such scenario confirms the arrival of the nanoparticulate material in the small intestine. In the next step, the in vivo absorption through the small intestine by intestinal perfusion experiments is conducted using the sought nanoparticles in Wistar rats. The quantification of Fe in the NPs Suspension before and after perfusion shows Fe absorption levels above 79%, never reported for other Fe treatments. Such high absorption levels do not seem to compromise cell viability, evaluated in enterocytes-like models (Caco-2 and HT-29) using cytotoxicity, ROS production, genotoxicity and lipid peroxidation tests. Moreover, regional differences in terms of Fe concentration are obtained among different parts of the small intestine as duodenum>jejunum>ileum. Complementary transmission electron microscopy (TEM) images show the presence of the intact particles around the intestinal microvilli without significant tissue damage. These studies show the high potential of these NP preparations for their use as oral management of anemia. KW - Iron nanoparticles KW - Anemia KW - ICP-MS KW - In vitro KW - In situ PY - 2020 DO - https://doi.org/10.1080/17435390.2019.1710613 VL - 14 IS - 3 SP - 388 EP - 403 PB - Taylor & Francis Online CY - London AN - OPUS4-50314 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Jakubowski, Norbert A1 - Müller, L. A1 - Traub, Heike A1 - Esteban-Fernández, D. A1 - Panne, Ulrich A1 - Herrmann, Antje A1 - Schellenberger, E. A1 - Theuring, F. A1 - Kneipp, Janina T1 - Imaging by laser ablation ICP-MS N2 - ICP-MS is a well-established analytical method which excels by high accuracy, high dynamic range and extremely low limits of detection for most metals. Furthermore ICP-MS offers a very high multi-element coverage so that many elements of the periodic table can be detected simultaneously. In this series of lectures, we want to focus on the historical developments, fundamentals, instrumentation and novel applications of ICP-MS in the life and material sciences. T2 - Ringvorlesung Analytik CY - Humboldt-Universität zu Berlin DA - 23.06.2017 KW - Laser ablation ICP-MS KW - Bio-Imaging PY - 2017 AN - OPUS4-40757 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Flores, E. A1 - Idrees, F. A1 - Moussay, P. A1 - Viallon, J. A1 - Wielgosz, R. A1 - Fernández, T. A1 - Ramírez, S. A1 - Rojo, A. A1 - Shinji, U. A1 - Waldén, J. A1 - Sega, M. A1 - Sang-Hyub, O. A1 - Macé, T. A1 - Couret, C. A1 - Qiao, H. A1 - Smeulders, D. A1 - Guenther, F.R. A1 - Thorn, W.J. III A1 - Tshilongo, J. A1 - Ntsasa, N.G. A1 - Stovcík, V. A1 - Valková, M. A1 - Konopelko, L. A1 - Gromova, E. A1 - Nieuwenkamp, G. A1 - Wessel, R. M. A1 - Milton, M. A1 - Harling, A. A1 - Vargha, G. A1 - Tuma, Dirk A1 - Kohl, Anka A1 - Schulz, Gert T1 - Final report on international comparison CCQM-K74: Nitrogen dioxide, 10 µmol/mol N2 - There is a high international priority attached to activities which reduce NOx in the atmosphere. The current level of permitted emissions is typically between 50 µmol/mol and 100 µmol/mol, but lower values are expected in the future. Currently, ambient air quality monitoring regulations also require the measurement of NOx mole fractions as low as 0.2 µmol/mol. The production of accurate standards at these levels of mole fractions requires either dilution of a stable higher concentration gas standard or production by a dynamic technique, for example one based on permeation tubes. The CCQM-K74 key comparison was designed to evaluate the level of comparability of National Metrology Institutes' measurement capabilities and standards for nitrogen dioxide (NO2) at a nominal mole fraction of 10 µmol/mol. The measurements of this key comparison took place from June 2009 to May 2010. Seventeen laboratories took part in this comparison coordinated by the BIPM and VSL. The key comparison reference value was based on BIPM measurement results, and the standard measurement uncertainty of the reference value was 0.042 µmol/mol. This key comparison demonstrated that the results of the majority of the participants agreed within limits of ±3% relative to the reference value. The results of only one laboratory lay significantly outside these limits. Likewise this comparison made clear that a full interpretation of the results of the comparison needed to take into account the presence of nitric acid (in the range 100 nmol/mol to 350 nmol/mol) in the cylinders circulated as part of the comparison, as well as the possible presence of nitric acid in the primary standards used by participating laboratories. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA). DatesIssue 1A (Technical Supplement 2012) KW - Ringversuch KW - NO2 KW - Spurenverunreinigungen KW - Meßverfahren PY - 2012 DO - https://doi.org/10.1088/0026-1394/49/1A/08005 SN - 0026-1394 SN - 1681-7575 VL - 49 IS - 08005 SP - 1 EP - 117 PB - Inst. of Physics Publ. CY - Bristol AN - OPUS4-25927 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fernandez-Menendez, L. J. A1 - Mendez-Lopez, C. A1 - Abad Andrade, Carlos Enrique A1 - Fandino, J. A1 - Gonzalez-Gago, C. A1 - Pisonero, J. A1 - Bordel, N. T1 - A critical evaluation of the chlorine quantification method based on molecular emission detection in LIBS N2 - The entire process involving the determination of Cl by molecular emission detection in Laser-Induced Breakdown Spectroscopy (LIBS) is thoroughly studied in this paper. This critical evaluation considers how spectra are normalized, how interferences from other molecular species signals are removed, and how signal integration is applied. Moreover, a data treatment protocol is proposed to achieve reliable and accurate Cl determination from the CaCl molecular spectral signal, not requiring the use of more complex numerical approaches. Calcium chloride dihydrate (CaCl2⋅2H2O) and high purity anhydrite samples (CaSO4) are used to optimize the acquisition conditions and data treatment of CaCl emission signal. Using the developed protocol, calibration curves for Cl, covering the concentration range from 0 μg/g to 60,000 μg/g of Cl, are successfully achieved. Finally, the suitability of the proposed methodology for Cl determination is successfully applied in industrial gypsum waste samples, where the results obtained by LIBS are validated using high-resolution molecular absorption spectroscopy (HR-CS-MAS) and potentiometric titration. KW - Laser induced breakdown Spectrocopy (LIBS) KW - Molecular spectra KW - Chlorine determination KW - CaCl emission bands KW - Industrial gypsum PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-544292 DO - https://doi.org/10.1016/j.sab.2022.106390 SN - 0584-8547 VL - 190 SP - 1 EP - 9 PB - Elsevier B.V. CY - Amsterdam, Netherlands AN - OPUS4-54429 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fernández, D. A1 - Vermeirssen, E.L.M. A1 - Bandow, Nicole A1 - Munoz, K. A1 - Schäfer, R.B. T1 - Calibration and field application of passive sampling for episodic exposure to polar organic pesticides in streams N2 - Rainfall-triggered runoff is a major driver of pesticide input in streams. Only few studies have examined the suitability of passive sampling to quantify such episodic exposures. In this study, we used Empore-TM styrene-divinylbenzene reverse phase sulfonated disks (SDB disks) and event-driven water samples (EDS) to assess exposure to 15 fungicides and 4 insecticides in 17 streams in a German vineyard area during 4 rainfall events. We also conducted a microcosm experiment to determine the SDB-disk sampling rates and provide a free-software solution to derive sampling rates under time-variable exposure. Sampling rates ranged from 0.26 to 0.77 L d-1 and time-weighted average (TWA) concentrations from 0.05 to 2.11 µg/L. The 2 sampling systems were in good agreement and EDS exceeded TWA concentrations on average by a factor of 3. Our study demonstrates that passive sampling is suitable to quantify episodic exposures from polar organic pesticides. KW - Passive sampling KW - Pesticide KW - Water monitoring KW - Freshwater PY - 2014 DO - https://doi.org/10.1016/j.envpol.2014.08.001 SN - 0269-7491 SN - 0013-9327 SN - 1873-6424 VL - 194 SP - 196 EP - 202 PB - Elsevier Ltd. CY - New York, NY [u.a.] AN - OPUS4-31277 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -