TY - JOUR A1 - Moraleja, I. A1 - Esteban-Fernández, Diego A1 - Lázaro, A. A1 - Humanes, B. A1 - Neumann, B. A1 - Tejedor, A. A1 - Mena, M. A1 - Jakubowski, Norbert A1 - Gómez-Gómez, M. T1 - Printing metal-spiked inks for LA-ICP-MS bioimaging internal standardization: comparison of the different nephrotoxic behavior of cisplatin, carboplatin, and oxaliplatin N2 - The study of the distribution of the cytostatic drugs cisplatin, carboplatin, and oxaliplatin along the kidney may help to understand their different nephrotoxic behavior. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) allows the acquisition of trace element images in biological tissues. However, results obtained are affected by several variations concerning the sample matrix and instrumental drifts. In this work, an internal standardization method based on printing an Ir-spiked ink onto the surface of the sample has been developed to evaluate the different distributions and accumulation levels of the aforementioned drugs along the kidney of a rat model. A conventional ink-jet printer was used to print fresh sagittal kidney tissue slices of 4 μm. A reproducible and homogenous deposition of the ink along the tissue was observed. The ink was partially absorbed on top of the tissue. Thus, this approach provides a pseudo-internal standardization, due to the fact that the ablation sample and internal standard take place subsequently and not simultaneously. A satisfactory normalization of LA-ICP-MS bioimages and therefore a reliable comparison of the kidney treated with different Pt-based drugs were achieved even for tissues analyzed on different days. Due to the complete ablation of the sample, the transport of the ablated internal standard and tissue to the inductively coupled plasma-mass spectrometry (ICP-MS) is practically taking place at the same time. Pt accumulation in the kidney was observed in accordance to the dosages administered for each drug. Although the accumulation rate of cisplatin and oxaliplatin is high in both cases, their Pt distributions differ. The strong nephrotoxicity observed for cisplatin and the absence of such side effect in the case of oxaliplatin could explain these distribution differences. The homogeneous distribution of oxaliplatin in the cortical and medullar areas could be related with its higher affinity for cellular transporters such as MATE2-k. KW - Bioimaging KW - LA-ICP-MS KW - Cisplatin KW - Standardization KW - Printed internal standard KW - Pt-based drugs KW - Nephrotoxicity PY - 2016 DO - https://doi.org/10.1007/s00216-016-9327-0 SN - 1618-2642 SN - 1618-2650 VL - 408 IS - 9 SP - 2309 EP - 2318 AN - OPUS4-36110 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scharlach, C. A1 - Müller, Larissa A1 - Wagner, S. A1 - Kobayashi, Y. A1 - Kratz, H. A1 - Ebert, M. A1 - Jakubowski, Norbert A1 - Schellenberger, E. T1 - LA-ICP-MS allows quantitative microscopy of europium-doped iron oxide nanoparticles and is a possible alternative to ambiguous Prussian blue iron staining N2 - The development of iron oxide nanoparticles for biomedical applications requires accurate histological evaluation. Prussian blue iron staining is widely used but may be unspecific when tissues contain substantial endogenous iron. Here we tested whether microscopy by laser ablation coupled to inductively coupled plasma mass spectrometry (LA-ICP-MS) is sensitive enough to analyze accumulation of very small iron oxide particles (VSOP) doped with europium in tissue sections. KW - Atherosclerotic plaques KW - LA-ICP-MS microscopy KW - Quantification KW - Element microscopy KW - Histology PY - 2016 DO - https://doi.org/10.1166/jbn.2016.2230 SN - 1550-7033 SN - 1550-7041 VL - 12 IS - 5 SP - 1001 EP - 1010 AN - OPUS4-36189 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Munter, L.M. A1 - Sieg, H. A1 - Bethge, T. A1 - Liebsch, F. A1 - Bierkandt, Frank A1 - Schleeger, M. A1 - Bittner, H.J. A1 - Heberle, J. A1 - Jakubowski, Norbert A1 - Hildebrand, P.W. A1 - Multhaup, G. T1 - Model peptides uncover the role of the beta-secretase transmembrane sequence in metal ion mediated oligomerization N2 - The β-secretase or β-site amyloid precursor protein cleaving enzyme 1 (BACE1) is the enzyme responsible for the formation of amyloid-β peptides, which have a major role in Alzheimer pathogenesis. BACE1 has a transmembrane sequence (TMS), which makes it unique among related proteases. We noticed that the BACE1 TMS contains an uncommon sulfur-rich motif. The sequence MxxxCxxxMxxxCxMxC spans the entire TMS, resembles metal ion binding motifs, and is highly conserved among homologues. We used a synthetic 31-mer model peptide comprising the TMS to study metal ion binding and oligomerization. Applying diverse biochemical and biophysical techniques, we detected dimer and trimer formation of the TMS peptide with copper ions. Replacement of the central Cys466 by Ala essentially abolished these effects. We show that the peptide undergoes a redox reaction with copper ions resulting in a disulfide bridge involving Cys466. Further, we find peptide trimerization that depends on the presence of monovalent copper ions and the sulfhydryl group of Cys466. We identified Cys466 as a key residue for metal ion chelation and to be the core of an oligomerization motif of the BACE1-TMS peptide. Our results demonstrate a novel metal ion controlled oligomerization of the BACE1 TMS, which could have an enormous therapeutic importance against Alzheimer disease. KW - Enzymes KW - Amyloid formation KW - Alzheimer disease KW - Copper PY - 2013 DO - https://doi.org/10.1021/ja410812r SN - 0002-7863 SN - 1520-5126 VL - 135 IS - 51 SP - 19354 EP - 19361 PB - American Chemical Society CY - Washington, DC AN - OPUS4-30543 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hösl, Simone A1 - Neumann, B. A1 - Techritz, Sandra A1 - Linscheid, M. A1 - Theuring, F. A1 - Scheler, C. A1 - Jakubowski, Norbert A1 - Müller, Larissa T1 - Development of a calibration and standardization procedure for LA-ICP-MS using a conventional ink-jet printer for quantification of proteins in electro- and western-blot assays N2 - We developed new procedures for internal standardization and calibration to be used for laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for elemental micro mapping imaging of biological samples like Western blot membranes and tissue sections. These procedures are based on printing of metal spiked inks onto the top of thin layer samples for simultaneous internal standardization and calibration of LA-ICP-MS. In the case of internal standardization the ink is spiked with indium as an internal standard and homogenously printed over the entire membrane (size 56 cm2) prior to LA-ICP-MS detection, a standard deviation (RSD) value of 2% was achieved. In the second approach the metal content of lanthanide tagged proteins and antibodies after biological work flows was quantified by LA-ICP-MS on nitro-cellulose membranes. In this case the inks spiked with varying metals were printed with different densities on the same nitrocellulose membranes in well-defined squares to produce matrix-matched calibration standards. For validation and calibration the ink squares were excised and the specific metal content was measured by liquid ICP-MS after solubilization of the membrane slice. For the printed calibration standard limits of detection (LOD) of <4 fmol for different metals and relative process standard deviations of 1–2% only were determined via LA-ICP-MS. PY - 2014 DO - https://doi.org/10.1039/c4ja00060a SN - 0267-9477 SN - 1364-5544 VL - 29 IS - 7 SP - 1282 EP - 1291 PB - Royal Society of Chemistry CY - London AN - OPUS4-31171 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Drescher, Daniela A1 - Zeise, Ingrid A1 - Traub, Heike A1 - Guttmann, P. A1 - Seifert, Stephan A1 - Büchner, Tina A1 - Jakubowski, Norbert A1 - Schneider, G. A1 - Kneipp, Janina T1 - In situ characterization of SiO2 nanoparticle biointeractions using BrightSilica N2 - By adding a gold core to silica nanoparticles (BrightSilica), silica-like nanoparticles are generated that, unlike unmodified silica nanoparticles, provide three types of complementary information to investigate the silica nano-biointeraction inside eukaryotic cells in situ. Firstly, organic molecules in proximity of and penetrating into the silica shell in live cells are monitored by surface-enhanced Raman scattering (SERS). The SERS data show interaction of the hybrid silica particles with tyrosine, cysteine and phenylalanine side chains of adsorbed proteins. Composition of the biomolecular corona of BrightSilica nanoparticles differs in fibroblast and macrophage cells. Secondly, quantification of the BrightSilica nanoparticles using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) micromapping indicates a different interaction of silica nanoparticles compared to gold nanoparticles under the same experimental conditions. Thirdly, the metal cores allow the investigation of particle distribution and interaction in the cellular ultrastructure by cryo nanoscale X-ray tomography (cryo-XT). In 3D reconstructions the assumption is confirmed that BrightSilica nanoparticles enter cells by an endocytotic mechanism. The high SERS intensities are explained by the beneficial plasmonic properties due to agglomeration of BrightSilica. The results have implications for the development of multi-modal qualitative and quantitative characterization in comparative nanotoxicology and bionanotechnology. KW - Silica nanoparticles KW - Surface-enhanced Raman scattering KW - X-ray tomography KW - LA-ICP-MS KW - Core–shell structures PY - 2014 DO - https://doi.org/10.1002/adfm.201304126 SN - 1616-301X SN - 1616-3028 VL - 24 IS - 24 SP - 3765 EP - 3775 PB - Wiley-VCH CY - Weinheim AN - OPUS4-30924 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Larissa A1 - Traub, Heike A1 - Jakubowski, Norbert A1 - Drescher, Daniela A1 - Baranov, Vladimir A1 - Kneipp, Janina T1 - Trends in single-cell analysis by use of ICP-MS N2 - The analysis of single cells is a growing research field in many disciplines such as toxicology, medical diagnosis, drug and cancer research or metallomics, and different methods based on microscopic, mass spectrometric, and spectroscopic techniques are under investigation. This review focuses on the most recent trends in which inductively coupled plasma mass spectrometry (ICP-MS) and ICP optical emission spectrometry (ICP-OES) are applied for single-cell analysis using metal atoms being intrinsically present in cells, taken up by cells (e.g., nanoparticles), or which are artificially bound to a cell. For the latter, especially element tagged antibodies are of high interest and are discussed in the review. The application of different sample introduction systems for liquid analysis (pneumatic nebulization, droplet generation) and elemental imaging by laser ablation ICP-MS (LA-ICP-MS) of single cells are highlighted. Because of the high complexity of biological systems and for a better understanding of processes and dynamics of biologically or medically relevant cells, the authors discuss the idea of 'multimodal spectroscopies.' KW - Bioanalytical methods KW - Cell systems/single cell analysis KW - Mass spectrometry/ICP-MS PY - 2014 DO - https://doi.org/10.1007/s00216-014-8143-7 SN - 1618-2642 SN - 1618-2650 VL - 406 IS - 27 SP - 6963 EP - 6977 PB - Springer CY - Berlin AN - OPUS4-31717 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Büchner, Tina A1 - Drescher, Daniela A1 - Traub, Heike A1 - Schrade, P. A1 - Bachmann, S. A1 - Jakubowski, Norbert A1 - Kneipp, Janina T1 - Relating surface-enhanced Raman scattering signals of cells to gold nanoparticle aggregation as determined by LA-ICP-MS micromapping N2 - The cellular response to nanoparticle exposure is essential in various contexts, especially in nanotoxicity and nanomedicine. Here, 14-nm gold nanoparticles in 3T3 fibroblast cells are investigated in a series of pulse-chase experiments with a 30-min incubation pulse and chase times ranging from 15 min to 48 h. The gold nanoparticles and their aggregates are quantified inside the cellular ultrastructure by laser ablation inductively coupled plasma mass spectrometry micromapping and evaluated regarding the surface-enhanced Raman scattering (SERS) signals. In this way, both information about their localization at the micrometre scale and their molecular nanoenvironment, respectively, is obtained and can be related. Thus, the nanoparticle pathway from endocytotic uptake, intracellular processing, to cell division can be followed. It is shown that the ability of the intracellular nanoparticles and their accumulations and aggregates to support high SERS signals is neither directly related to nanoparticle amount nor to high local nanoparticle densities. The SERS data indicate that aggregate geometry and interparticle distances in the cell must change in the course of endosomal maturation and play a critical role for a specific gold nanoparticle type in order to act as efficient SERS nanoprobe. This finding is supported by TEM images, showing only a minor portion of aggregates that present small interparticle spacing. The SERS spectra obtained after different chase times show a changing composition and/or structure of the biomolecule corona of the gold nanoparticles as a consequence of endosomal processing. KW - Gold nanoparticles KW - Surface-enhanced Raman scattering KW - LA-ICP-MS KW - Fibroblast KW - Cell KW - Particle aggregation KW - Endosome PY - 2014 DO - https://doi.org/10.1007/s00216-014-8069-0 SN - 1618-2642 SN - 1618-2650 VL - 406 IS - 27 SP - 7003 EP - 7014 PB - Springer CY - Berlin AN - OPUS4-31718 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Larissa A1 - Jakubowski, Norbert A1 - Hayen, H. A1 - Roos, P.H. T1 - Iodination of proteins, proteomes and antibodies with potassium triodide for LA-ICP-MS based proteomic analyses N2 - A fast and mild method for iodine labelling of proteins is presented which is specifically designed and optimized for laser ablation (LA-)ICP-MS based proteomics. Single proteins (lysozyme, bovine serum albumin, cytochrome c and β-casein), whole proteomes (microsomal proteome of rats) and antibodies (anti-bovine casein, anti-bovine serum albumin) can be efficiently iodinated by means of potassium triiodide with minimal losses of antigen properties and antibody binding to iodinated proteins. A comparison with iodination by use of IODO-Beads is presented and it is shown that triiodide labelling is a fast, cheap and less laborious alternative without compromising the analytical figures of merit. PY - 2011 DO - https://doi.org/10.1039/c1ja10090d SN - 0267-9477 SN - 1364-5544 N1 - Geburtsname von Müller, Larissa: Wäntig, L. - Birth name of Müller, Larissa: Wäntig, L. VL - 26 SP - 1610 EP - 1618 PB - Royal Society of Chemistry CY - London AN - OPUS4-24209 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Larissa A1 - Jakubowski, Norbert A1 - Roos, P.H. T1 - Multi-parametric analysis of cytochrome P450 expression in rat liver microsomes by LA-ICP-MS N2 - Quantitative analysis of cytochrome P450 (CYP) patterns of cells and tissues is an important aspect in toxicological and pharmacological research as this group of enzymes is largely involved in the metabolism of toxic compounds and drugs. Here we present a method for the multi-parametric and simultaneous quantitative determination of several cytochromes P450 in liver microsomes of untreated and inducer treated rats. The method is based on the binding of specifically lanthanide labelled antibodies to electrophoretically separated and blotted CYP proteins and their subsequent identification and quantification by LA-ICP-MS. CYP1A1, CYP2B1, CYP2C11, CYP2E1 and CYP3A1 were simultaneously quantified and the patterns between microsomal samples were compared. Microsomes of rats treated with 3-methylcholanthrene, phenobarbital and dexamethasone showed increased levels of CYP1A1, CYP2B1 and CYP3A1, respectively. These results coincide with data obtained by independent methods for CYP quantification, i.e. ethoxyresorufin O-deethylase activity for CYP1A1 and pentoxyresorufin O-depentylase for CYP2B1. The presented method is useful for multi-parametric CYP profiling and has further large potential with respect to the number of analysed parameters/proteins and sensitivity. PY - 2011 DO - https://doi.org/10.1039/c0ja00077a SN - 0267-9477 SN - 1364-5544 N1 - Geburtsname von Müller, Larissa: Wäntig, L. - Birth name of Müller, Larissa: Wäntig, L. VL - 26 IS - 2 SP - 310 EP - 319 PB - Royal Society of Chemistry CY - London AN - OPUS4-23465 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jakubowski, Norbert A1 - Prohaska, T. A1 - Rottmann, L. A1 - Vanhaecke, F. T1 - Inductively coupled plasma- and glow discharge plasma-sector field mass spectrometry - Part I. Tutorial: Fundamentals and instrumentation N2 - The aim of this series of two reviews is to introduce the basic concepts of ICP and GD sector field instruments, to discuss their peculiarities and performance, to present selected analytical applications for demonstration of the 'state of the art' and, finally, to identify possible future trends and developments. Part I focuses on fundamentals, instrumentation and operation of instruments to give an overview of the capabilities of the actual commercially available instrumentation, whereas selected applications will be discussed in detail in part II. PY - 2011 DO - https://doi.org/10.1039/c0ja00161a SN - 0267-9477 SN - 1364-5544 VL - 26 IS - 4 SP - 693 EP - 726 PB - Royal Society of Chemistry CY - London AN - OPUS4-23466 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jakubowski, Norbert T1 - Inductively coupled plasma- and glow discharge plasma-sector field mass spectrometry - Part II. Applications N2 - Part I of this series of two reviews focused on fundamentals, instrumentation and operation of sector field instruments to give a proper overview of the capabilities of the actual commercially available instrumentation. In part II, selected applications of the last decade are discussed in detail concluding with pinpointing possible future trends and current developments. KW - ICP KW - SF KW - MS PY - 2011 DO - https://doi.org/10.1039/c0ja00007h SN - 0267-9477 SN - 1364-5544 VL - 26 IS - 4 SP - 727 EP - 757 PB - Royal Society of Chemistry CY - London AN - OPUS4-23467 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pedrero, Z. A1 - Murillo, S. A1 - Cámara, C. A1 - Schram, E. A1 - Luten, J.B. A1 - Feldmann, I. A1 - Jakubowski, Norbert A1 - Madrid, Y. T1 - Selenium speciation in different organs of African catfish (Clarias gariepinus) enriched through a selenium-enriched garlic based diet N2 - Speciation of Se in fish is needed to elucidate the metabolism of this element in living organisms in the marine environment. In this paper, selenium concentration and its species distribution in several organs and tissues (liver, gills, kidney, muscle and gastrointestinal tract) of African catfish fed with a selenium-enriched garlic based diet was studied. The intention of this paper is focused on both the investigation of selenium distribution in the soluble protein fraction and the detection of selenoaminoacids. Thus, two different procedures have been developed. In the first procedure, screening of selenium in proteins in the Tris-buffer soluble fraction of different tissues was carried out by size exclusion chromatography-inductively coupled plasma-mass spectrometry (SEC-ICP-MS) and by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) after sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) separation and electroblotting onto membranes. For the amino acid analysis, several sample treatments for Se-species extraction, based on enzymatic hydrolysis, were compared. The best results were obtained for incubation at controlled temperature. Application of several sample treatments in conjunction with different chromatographic techniques (reverse phase, anion exchange and ion exchange/size exclusion) was crucial to unambiguous Se-species identification. In Se-enriched African catfish a noticeable increase in the content of selenium in different organs was observed, except for the liver, where the Se level remained unaltered. The kidney was the Se-target organ in animals fed with enriched Se food. Selenomethionine (SeMet) was the main Se species identified in fillet extracts, whereas the presence of selenocysteine (SeCys) was detected in the liver and both SeMet and SeCys were present in the kidney. PY - 2011 DO - https://doi.org/10.1039/c003889j SN - 0267-9477 SN - 1364-5544 VL - 26 IS - 1 SP - 116 EP - 125 PB - Royal Society of Chemistry CY - London AN - OPUS4-22981 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmidt, Benita A1 - Pergantis, S. A. A1 - Esteban-Fernández, Diego A1 - Jakubowski, Norbert A1 - Günther, D. T1 - Investigation of a combined microdroplet generator and pneumatic nebulization system for rapid quantitative determination of metal-containing nanoparticles using ICP-MS N2 - In this work, a routinely applicable approach is presented to characterize metal NPs. Individual droplets generated from a microdroplet generator (MDG) were merged into an aerosol generated by a pneumatic nebulizer (PN) and introduced into an ICPMS. The MDG offers high transport efficiency of individual and discrete droplets and was therefore used to establish a calibration function for mass quantification of NPs which were introduced through the PN following the single particle procedure as described elsewhere. The major advantages of such a combined configuration include fast processing of large sample volumes, fast exchanges of different sample matrixes, and the calibration of the NP signal using traceable elemental standards, thus avoiding the need to use NP reference materials or other, not always thoroughly characterized, commercially available NPs. The transport efficiency of the sample introduction is calculated based on the fact that 100% of the calibrant reaches the plasma through the MDG, whereas for the PN a NP suspension containing a known number concentration is used. Alternatively, bulk analysis of the NP material allows transport efficiency determination without any additional information from reference NPs. With this method, we could determine the size of standard silver NPs at 60.4 ± 1.0 nm and 80.0 ± 1.4 nm, respectively, which agrees with the size ranges given by the supplier (60.8 ± 6.6 nm and 79.8 ± 5.4 nm). Furthermore, we were also able to determine the NPs number concentration of the sample (Ag/Au) with a deviation of 3.2% the expected value. KW - Nanoparticles KW - ICP-MS KW - Microdroplet generator PY - 2015 DO - https://doi.org/10.1021/acs.analchem.5b01604 SN - 0003-2700 SN - 1520-6882 VL - 87 IS - 17 SP - 8687 EP - 8694 PB - American Chemical Society CY - Washington, DC AN - OPUS4-34803 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Richter, Janine A1 - Fettig, Ina A1 - Philipp, Rosemarie A1 - Jakubowski, Norbert T1 - Tributyltin - critical pollutant in whole water samples - development of traceable measurement methods for monitoring under the European water framework directive (WFD) 2000/60/EC N2 - Tributyltin is listed as one of the priority substances in the European Water Framework Directive (WFD). Despite its decreasing input in the environment, it is still present and has to be monitored. In the European Metrology Research Programme project ENV08, a sensitive and reliable analytical method according to the WFD was developed to quantify this environmental pollutant at a very low limit of quantification. With the development of such a primary reference method for tributyltin, the project helped to improve the quality and comparability of monitoring data. An overview of project aims and potential analytical tools is given. KW - Tributyltin KW - European Water Framework Directive KW - Whole water body KW - Reference method PY - 2015 DO - https://doi.org/10.1007/s11356-015-4614-4 SN - 0944-1344 SN - 1614-7499 VL - 22 IS - 13 SP - 9589 EP - 9594 PB - Springer CY - Berlin; Heidelberg AN - OPUS4-33734 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 - Laux, P. A1 - Tentschert, J. A1 - Riebeling, Ch. A1 - Braeuning, A. A1 - Creutzenberg, O. A1 - Epp, A. A1 - Fessard, V. A1 - Haas, K.-H. A1 - Haase, A. A1 - Hund-Rinke, K. A1 - Jakubowski, Norbert A1 - Kearns, P. A1 - Lampen, A. A1 - Rauscher, H. A1 - Schoonjans, R. A1 - Störmer, A. A1 - Thielmann, A. A1 - Mühle, U. A1 - Luch, A. T1 - Nanomaterials: certain aspects of application, risk assessment and risk communication N2 - Development and market introduction of new nanomaterials trigger the need for an adequate risk assessment of such products alongside suitable risk communication measures. Current application of classical and new nanomaterials is analyzed in context of regulatory requirements and standardization for chemicals, food and consumer products. The challenges of nanomaterial characterization as the main bottleneck of risk assessment and regulation are presented. In some areas, e.g., quantification of nanomaterials within complex matrices, the establishment and adaptation of analytical techniques such as laser ablation inductively coupled plasma mass spectrometry and others are potentially suited to meet the requirements. As an example, we here provide an approach for the reliable characterization of human exposure to nanomaterials resulting from food packaging. Furthermore, results of nanomaterial toxicity and ecotoxicity testing are discussed, with concluding key criteria such as solubility and fiber rigidity as important parameters to be considered in material development and regulation. Although an analysis of the public opinion has revealed a distinguished rating depending on the particular field of application, a rather positive perception of nanotechnology could be ascertained for the German public in general. An improvement of material characterization in both toxicological testing as well as end-product control was concluded as being the main obstacle to ensure not only safe use of materials, but also wide acceptance of this and any novel technology in the general public. KW - Nanomaterials KW - Toxicity KW - Ecotoxicity KW - Standardization KW - Exposure PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-441096 DO - https://doi.org/10.1007/s00204-017-2144-1 VL - 92 IS - 1 SP - 121 EP - 141 PB - Springer AN - OPUS4-44109 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meyer, S. A1 - López-Serrano, Ana A1 - Mitze, H. A1 - Jakubowski, Norbert A1 - Schwerdtle, T. T1 - Single-cell analysis by ICP-MS/MS as a fast tool for cellular bioavailability studies of arsenite N2 - Single-cell inductively coupled plasma mass spectrometry (SC-ICP-MS) has become a powerful and fast tool to evaluate the elemental composition at a single-cell level. In this study, the cellular bioavailability of arsenite (incubation of 25 and 50 μM for 0-48 h) has been successfully assessed by SC-ICP-MS/MS for the first time directly after re-suspending the cells in water. This procedure avoids the normally arising cell membrane permeabilization caused by cell fixation methods (e.g. methanol fixation). The reliability and feasibility of this SC-ICP-MS/MS approach with a limit of detection of 0.35 fg per cell was validated by conventional bulk ICP-MS/MS analysis after cell digestion and parallel measurement of sulfur and phosphorus. KW - Single-cell analysis KW - ICP-MS/MS KW - Arsenite PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-441105 DO - https://doi.org/10.1039/c7mt00285h SN - 1756-5901 VL - 10 IS - 1 SP - 73 EP - 76 PB - RSC Publ. CY - Cambridge AN - OPUS4-44110 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 - Pisonero, J. A1 - Bouzas-Ramos, D. A1 - Traub, Heike A1 - Cappella, Brunero A1 - Alvarez-Llamas, C. A1 - Richter, Silke A1 - Mayo, J. C. A1 - Costa-Fernandez, J. M. A1 - Bordel, N. A1 - Jakubowski, Norbert T1 - Critical evaluation of fast and highly resolved elemental distribution in single cells using LA-ICP-SFMS N2 - The analytical potential of a nanosecond laser ablation inductively coupled plasma mass spectrometer (ns-LA-ICP-SFMS) system, equipped with an ultra-fast wash-out ablation chamber, is critically investigated for fast and highly spatially resolved (∼μm) qualitative elemental distribution within single cells. Initially, a low surface roughness (< 10 nm) thin In–SnO2 layer (total coating thickness ∼200 nm) deposited on glass is employed to investigate the size, morphology and overlapping of laser-induced craters obtained at different laser repetition rates, making use of Atomic Force Microscopy (AFM). Conical craters with a surface diameter of about 2 µm and depths of about 100 nm were measured after a single laser shot. Furthermore, the influence of the sampling distance (i.e. distance between the sample surface and the inner sniffer of the ablation chamber) on the LA-ICP-MS ion signal wash-out time is evaluated. A significant decrease of the transient 120Sn+ ion signal is noticed after slight variations (±200 μm) around the optimum sampling position. Ultra-fast wash-outs (< 10 ms) are achieved reducing the aerosol mixing from consecutive laser shots even when operating the laser at high repetition rates (25 – 100 Hz). Fast and highly spatially resolved images of elemental distribution within mouse embryonic fibroblast cells (NIH/3T3 fibroblast cells) and human cervical carcinoma cells (HeLa cells), incubated with gold nanoparticles (Au NPs) and Cd-based quantum dots (QDs), respectively, are determined at the optimized operating conditions. Elemental distribution of Au and Cd in single cells is achieved using a high scanning speed (50 µm/s) and high repetition rate (100 Hz). The results obtained for the distribution of fluorescent Cd-based QDs within the HeLa cells are in good agreement with those obtained by confocal microscopy. The size, morphology and overlapping of laser-induced craters in the fixed cells are also investigated using AFM, observing conical craters with a surface diameter of about 2.5 µm and depths of about 800 nm after a single laser shot. KW - Laser ablation KW - ICP-MS KW - Nanoparticle KW - Atomic Force Microscopy KW - Cell PY - 2018 DO - https://doi.org/10.1039/c8ja00096d SP - 1 EP - 9 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-45564 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kirilina, E. A1 - Helbling, S. A1 - Morawski, M. A1 - Pine, K. A1 - Reimann, K. A1 - Jankuhn, S. A1 - Dinse, J. A1 - Deistung, A. A1 - Reichenbach, J. R. A1 - Trampel, R. A1 - Geyer, S. A1 - Müller, Larissa A1 - Jakubowski, Norbert A1 - Arendt, T. A1 - Bazin, P.-L. A1 - Weiskopf, N. T1 - Superficial white matter imaging: Contrast mechanisms and whole-brain in vivo mapping N2 - Superficial white matter (SWM) contains the most cortico-cortical white matter connections in the human brain encompassing the short U-shaped association fibers. Despite its importance for brain connectivity, very little is known about SWM in humans, mainly due to the lack of noninvasive imaging methods. Here, we lay the groundwork for systematic in vivo SWM mapping using ultrahigh resolution 7 T magnetic resonance imaging. Using biophysical modeling informed by quantitative ion beam microscopy on postmortem brain tissue, we demonstrate that MR contrast in SWM is driven by iron and can be linked to the microscopic iron distribution. Higher SWM iron concentrations were observed in U-fiber–rich frontal, temporal, and parietal areas, potentially reflecting high fiber density or late myelination in these areas. Our SWM mapping approach provides the foundation for systematic studies of interindividual differences, plasticity, and pathologies of this crucial structure for cortico-cortical connectivity in humans. KW - Magnetic resonance imaging KW - Laser ablation KW - ICP-MS KW - Brain KW - Imaging PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-514430 DO - https://doi.org/10.1126/sciadv.aaz9281 SN - 2375-2548 VL - 6 IS - 41 SP - eaaz9281 PB - American Association for the Advancement of Science (Science/AAAS) CY - Washington, DC, USA AN - OPUS4-51443 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -