TY - CONF A1 - Bierkandt, Frank A1 - Reichardt, Ph. A1 - Haase, A. A1 - Jungnickel, H. A1 - Tentschert, J. A1 - Pfaff, K. A1 - Luch, A. A1 - Jakubowski, Norbert T1 - Laserablation-ICP-MS analysis of cell lysates after silver nanoparticle treatment: Is quantification possible? T2 - European Winter Conference on Plasma Spectrochemistry CY - Kraków, Poland DA - 2013-02-10 PY - 2013 AN - OPUS4-28036 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bierkandt, Frank A1 - Müller, Larissa A1 - Techritz, Sandra A1 - Jakubowski, Norbert A1 - Roos, Peter H. A1 - Linscheid, M. T1 - Quantitative Analyse phosphorylierter Proteine mittels LA-ICP-MS T2 - 46. Jahrestagung der Deutschen Gesellschaft für Massenspektrometrie CY - Berlin, Germany DA - 2013-03-10 PY - 2013 N1 - Geburtsname von Müller, Larissa: Wäntig, L. - Birth name of Müller, Larissa: Wäntig, L. AN - OPUS4-28038 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bierkandt, Frank A1 - Jakubowski, Norbert A1 - Linscheid, M. T1 - Quantitative Analysis of Phosphorylated Proteins with LA-ICP-MS T2 - European Winter Conference on Plasma Spectrochemistry 2013 CY - Kraków, Poland DA - 2013-02-10 PY - 2013 AN - OPUS4-27898 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Esteban-Fernández, D. A1 - Bierkandt, Frank A1 - Linscheid, M.W. T1 - MeCAT labeling for absolute quantification of intact proteins using labelspecific isotope dilution ICP-MS N2 - Sensitive, accurate and fast absolute quantification of intact proteins is reported using metal coded affinity tags (MeCATs) combined with gel electrophoresis (GE) separation, inductively coupled plasma mass spectrometry (ICP-MS) detection and label-specific isotope dilution analysis quantification. Two different approaches were investigated concerning the introduction of the sample into ICP-MS, mineralization of the gel and direct laser ablation (LA) of the spot. Three major advantages are remarkable in the proposed method. First, not only heteroatom-containing proteins but also all labeled proteins in the sample can be absolutely quantified preparing an isotopically enriched tracer. On the other hand, highly sensitive determination in the amol range can be performed, considerably reducing the analysis time due to the straightforward measurements by ICP-MS. Furthermore, the studied method allows accurate quantifications with different sample-to-spike ratios and using stock spikes stored for months. After the first characterization using standard proteins, human serum albumin (HSA) and transferrin (Tf) were determined in human serum to test the applicability of the method to biological samples. The results show satisfactory quantifications for the studied proteins despite the difference in concentration and the similarity in migration distances. PY - 2012 U6 - https://doi.org/10.1039/c2ja30137g SN - 0267-9477 SN - 1364-5544 VL - 27 IS - 10 SP - 1701 EP - 1708 PB - Royal Society of Chemistry CY - London AN - OPUS4-27777 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bierkandt, Frank A1 - Reichardt, Ph. A1 - Haase, A. A1 - Jungnickel, H. A1 - Tentschert, J. A1 - Luch, A. A1 - Jakubowski, Norbert T1 - Quantitative Analyse der Silbernanopartikelaufnahme durch Zellen mittels LA-ICP-MS T2 - Adlershofer Forschungsforum CY - Berlin, Germany DA - 2013-11-12 PY - 2013 AN - OPUS4-29551 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bierkandt, Frank A1 - Jakubowski, Norbert A1 - Linscheid, M. T1 - Quantitative Analysis of Phosphorylated Proteins with LA-ICP-MS T2 - 11th European Workshop on Laser Ablation CY - Gijón, Spain DA - 2012-06-16 PY - 2012 AN - OPUS4-26476 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hsiao, I.-L. A1 - Bierkandt, Frank A1 - Reichardt, Ph. A1 - Luch, A. A1 - Huang, Y.-J. A1 - Jakubowski, Norbert A1 - Tentschert, J. A1 - Haase, A. T1 - Quantification and visualization of cellular uptake of TiO2 and Ag nanoparticles: comparison of different ICP-MS techniques N2 - Safety assessment of nanoparticles (NPs) requires techniques that are suitable to quantify tissue and cellular uptake of NPs. The most commonly applied techniques for this purpose are based on inductively coupled plasma mass spectrometry (ICP-MS). Here we apply and compare three different ICP-MS methods to investigate the cellular uptake of TiO2 (diameter 7 or 20 nm, respectively) and Ag (diameter 50 or 75 nm, respectively) NPs into differentiated mouse neuroblastoma cells (Neuro-2a cells). Cells were incubated with different amounts of the NPs. Thereafter they were either directly analyzed by laser ablation ICP-MS (LA-ICP-MS) or were lysed and lysates were analyzed by ICP-MS and by single particle ICP-MS (SP-ICP-MS). KW - Nanoparticles KW - Single particle ICP-MS KW - Laser ablation ICP-MS KW - Cellular internalization KW - Neurons PY - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-371620 SN - 1477-3155 VL - 14 SP - Article 50 AN - OPUS4-37162 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 U6 - 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 - CONF A1 - Bierkandt, Frank A1 - Reichardt, Ph. A1 - Haase, A. A1 - Jungnickel, H. A1 - Tentschert, J. A1 - Luch, A. A1 - Jakubowski, Norbert T1 - Quantitative Analyse der Silbernanopartikelaufnahme durch Zellen mittels LA-ICP-MS T2 - Anwendertreffen Plasmaspektrometrie 2014 CY - Hamburg, Germany DA - 2014-02-11 PY - 2014 AN - OPUS4-30363 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sötebier, Carina A1 - Bierkandt, Frank A1 - Rades, Steffi A1 - Jakubowski, Norbert A1 - Panne, Ulrich A1 - Weidner, Steffen T1 - Sample loss in asymmetric flow field-flow fractionation coupled to inductively coupled plasma-mass spectrometry of silver nanoparticles N2 - In this work, sample losses of silver nanoparticles (Ag NPs) in asymmetrical flow field-flow fractionation (AF4) have been systematically investigated with the main focus on instrumental conditions like focusing and cross-flow parameters as well as sample concentration and buffer composition. Special attention was drawn to the AF4 membrane. For monitoring possible silver depositions on the membrane, imaging laser ablation coupled to inductively coupled plasma mass spectrometry (LA-ICP-MS) was used. Our results show that the sample residue on the membrane was below 0.6% of the total injected amount and therefore could be almost completely avoided at low sample concentrations and optimized conditions. By investigation of the AF4 flows using inductively coupled plasma mass spectrometry (ICP-MS), we found the recovery rate in the detector flow under optimized conditions to be nearly 90%, while the cross-flow, slot-outlet flow and purge flow showed negligible amounts of under 0.5%. The analysis of an aqueous ionic Ag standard solution resulted in recovery rates of over 6% and the ionic Ag content in the sample was found to be nearly 8%. Therefore, we were able to indicate the ionic Ag content as the most important source of sample loss in this study. KW - Asymmetric flow filed-flow fractionation KW - ICP-MS KW - Nanoparticles KW - Sample loss KW - Quantification PY - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-336171 SN - 0267-9477 SN - 1364-5544 VL - 30 IS - 10 SP - 2214 EP - 2222 PB - Royal Society of Chemistry CY - London AN - OPUS4-33617 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hea, Y. A1 - Esteban-Fernandez, Diego A1 - Neumann, B. A1 - Bergmann, U. A1 - Bierkandt, Frank A1 - Linscheid, M. W. T1 - Application of MeCAT-Click labeling for protein abundance characterization of E. coli after heat shock experiments N2 - In a proof of concept study, metal-coded affinity tags based on click chemistry (MeCAT-Click) were used to analyze the proteome of Escherichia coli (E. coli) in response to heat stress. This allows high labeling efficiency, high detection sensitivity, and multiplex capabilities, which are pivotal for its application to protein quantification. Two approaches are presented for relative quantification of differentially lanthanide-labeled proteins. The first approach uses isotope-labeling, where ESI-MS was utilized to quantify the differentially labeled proteins from different states of E. coli. With this approach, 14 proteins were found with changed abundance, among them five proteins upregulated. In the second approach, differentially labeled samples were separated by two dimensional gel electrophoresis (2 DE) and scanned by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Comparison of the signal intensities of the different lanthanides was used to quantify different sample states. Based on this information, ESI-MS was used to identify the proteins with different abundance. The sensitivity of LA-ICP-MS allowed us to find one upregulated protein that was nearly invisible by silver staining ("Probable replication endonuclease from retron EC67"). The advantage of this approach is to locate low abundant proteins with differential expression using LA-ICP-MS, which may be overlooked otherwise. Biological significance: This paper demonstrates the successful application of a novel metal labeling strategy to quantify the proteins from complex biological samples. In comparison with former metal labeling strategies, it reduces the steric hindrance and improves the labeling efficiency during the labeling process, which ensure its successful application. This methodology is compatible with both molecular and elemental mass spectrometry. ESI-MS/MS in combination with software-based search allows the identification and relative quantification of labeled proteins. In addition, LA-ICP-MS helps to locate the labeled proteins in 2-DE gels with superior detection capability, thus, target proteins with low abundance can be precisely followed. Its excellent sensitivity allows one to track the proteins of interest that are barely visible by silver staining. KW - Protein quantification KW - Heat shock response KW - Ln-MeCAT-Click labeling KW - nanoLC-ESI-MS/MS KW - 2-D electrophoresis KW - LA-ICP-MS PY - 2016 U6 - https://doi.org/10.1016/j.jprot.2015.12.010 SN - 1874-3919 VL - 136 SP - 68 EP - 76 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-35837 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -