TY - JOUR A1 - Michalik-Onichimowska, Aleksandra A1 - Kern, Simon A1 - Riedel, Jens A1 - Panne, Ulrich A1 - King, R. A1 - Maiwald, Michael T1 - ‘‘Click” analytics for ‘‘click” chemistry – A simple method for calibration–free evaluation of online NMR spectra N2 - Driven mostly by the search for chemical syntheses under biocompatible conditions, so called "click" chemistry rapidly became a growing field of research. The resulting simple one-pot reactions are so far only scarcely accompanied by an adequate optimization via comparably straightforward and robust analysis techniques possessing short set-up times. Here, we report on a fast and reliable calibration-free online NMR monitoring approach for technical mixtures. It combines a versatile fluidic system, continuous-flow measurement of 1H spectra with a time interval of 20 s per spectrum, and a robust, fully automated algorithm to interpret the obtained data. As a proof-of-concept, the thiol-ene coupling between N-boc cysteine methyl ester and allyl alcohol was conducted in a variety of non-deuterated solvents while its time-resolved behaviour was characterized with step tracer experiments. Overlapping signals in online spectra during thiol-ene coupling could be deconvoluted with a spectral model using indirect hard modeling and were subsequently converted to either molar ratios (using a calibrationfree approach) or absolute concentrations (using 1-point calibration). For various solvents the kinetic constant k for pseudo-first order reaction was estimated to be 3.9 h-1 at 25 °C. The obtained results were compared with direct integration of non-overlapping signals and showed good agreement with the implemented mass balance. KW - Online NMR Spectroscopy KW - Reaction Monitoring KW - Automated Data Evaluation KW - Thiol-ene click chemistry KW - Click Chemistry KW - Process Analytical Technology PY - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-393232 UR - http://www.sciencedirect.com/science/article/pii/S1090780717300575 VL - 277 SP - 154 EP - 161 PB - Elsevier Inc. CY - Oxford AN - OPUS4-39323 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Abad Andrade, Carlos Enrique A1 - Florek, S. A1 - Becker-Ross, H. A1 - Huang, M.-D. A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin A1 - Lippitz, Andreas A1 - Hodoroaba, Vasile-Dan A1 - Schmid, Thomas A1 - Heinrich, Hans-Joachim A1 - Recknagel, Sebastian A1 - Jakubowski, Norbert A1 - Panne, Ulrich T1 - Zirconium permanent modifiers for graphite furnaces used in absorption spectrometry: understanding their structure and mechanism of action N2 - The mechanism of action of zirconium permanent modifiers on graphite surfaces was investigated in order to understand its influence on the analytical signal in atomic and molecular absorption spectrometry (AAS/MAS). For this, the molecule formation of CaF was studied, which is used for the indirect analytical determination of fluorine in high-resolution continuum source graphite furnace molecular absorption spectrometry (HR-CS-GFMAS). The kinetics of this reaction was established by monitoring its molecular spectrum at different atomisation temperatures. An Arrhenius plot showed a pseudo-first order reaction with respect to fluorine (n = 1). An intermediate state was isolated, and its structure was elucidated by spectroscopic methods: scanning electron microscopy with energy dispersive X-ray spectroscopy (SEMEDX), X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XANES and EXAFS), and Raman microspectroscopy. We propose here a mechanism, where ZrO2 acts as a heterogeneous catalyst: after a pyrolytic step, an intermediate state of ZrO(OCaF) is activated, and at higher temperatures, CaF(g) is released from the zirconium-coated graphite surface. No evidence of the formation of zirconium carbide was found. Consequently, as the CaF formation is catalysed by a heterogeneous catalyst, surface modifications with ZrO2 nanoparticles and ZrO xerogels were investigated in order to increase the surface area. Their influence was evaluated in the molecule formation of CaF, CaCl, CaBr, and CaI. Graphite furnace modification with zirconium oxide nanoparticles proves to be the best choice for fluorine analysis with a signal enhancement of more than eleven times with respect a non-coated graphite furnace. However, the influence of zirconium modifications in the analytical signals of Cl, and I is lower than the F signals or even negative in case of the Br. Understanding zirconium modifiers as heterogeneous catalysts offers a new perspective to AAS and MAS, and reveals the potential of surface analytical methods for development of improved permanent modifiers and graphite furnace coatings. KW - Zirconium KW - HR-CS-MAS KW - Graphite furnace KW - Nanoparticles KW - Xerogel KW - Calcium monofluoride KW - Absorption spectrometry PY - 2018 UR - https://pubs.rsc.org/en/content/articlelanding/2018/ja/c8ja00190a U6 - https://doi.org/10.1039/C8JA00190A SN - 0267-9477 VL - 33 IS - 12 SP - 2034 EP - 2042 PB - Royal Society of Chemistry AN - OPUS4-46775 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rosenkranz, D. A1 - Kriegel, F. L. A1 - Mavrakis, E. A1 - Pergantis, S. A. A1 - Reichardt, P. A1 - Tentschert, J. A1 - Jakubowski, N. A1 - Laux, P. A1 - Panne, Ulrich A1 - Luch, A. T1 - Versatile dual-inlet sample introduction system for multi-mode single particle inductively coupled plasma mass spectrometry N2 - Metal-containing nanoparticles (NP) can be characterized with inductively coupled plasma mass spectrometers (ICP-MS) in terms of their size and number concentration by using the single-particle mode of the instrument (spICP-MS). The accuracy of measurement depends on the setup, operational conditions of the instrument and specific parameters that are set by the user. The transport efficiency of the ICP-MS is crucial for the quantification of the NP and usually requires a reference material with homogenous size distribution and a known particle number concentration. Currently, NP reference materials are available for only a few metals and in limited sizes. If particles are characterized without a reference standard, the results of both size and particle number may be biased. Therefore, a dual-inlet Setup for characterizing nanoparticles with spICP-MS was developed to overcome this problem. This setup is based on a conventional introduction system consisting of a pneumatic nebulizer (PN) for nanoparticle solutions and a microdroplet Generator (μDG) for ionic calibration solutions. A new and flexible interface was developed to facilitate the coupling of μDG, PN and the ICP-MS system. The interface consists of available laboratory components and allows for the calibration, nanoparticle (NP) characterization and cleaning of the arrangement, while the ICP-MS instrument is still running. Three independent analysis modes are available for determining particle size and number concentration. Each mode is based on a different calibration principle. While mode I (counting) and mode III (μDG) are known from the literature, mode II (sensitivity), is used to determine the transport efficiency by inorganic ionic Standard solutions only. It is independent of NP reference materials. The μDG based inlet system described here guarantees superior analyte sensitivities and, therefore, lower detection limits (LOD). The size dependent LODs achieved are less than 15 nm for all NP (Au, Ag, CeO2) investigated. KW - Spectrometer KW - Reference KW - Calibration PY - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-536121 SN - 1940-087X IS - 163 SP - 1 EP - 19 PB - MyJoVE Corporation CY - Cambridge, MA, USA AN - OPUS4-53612 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gopala, Anil A1 - Kipphardt, Heinrich A1 - Matschat, Ralf A1 - Panne, Ulrich T1 - Use of mass spectrometric detection as a versatile process monitoring tool: reduction patterns in a milled ZnO/Al mixture N2 - Mass spectrometric detection can play a prominent role in the assessment of different reactions occurring at varied temperatures in a milled ZnO/Al mixture. This is the first time that online mass spectrometric information was used as a tool for monitoring and understanding the chemical reduction process mechanism. We have observed four different types of reaction taking place: (1) distillation of Zn metal, (2) reduction of ZnO by activated Al, (3) melting of Al and finally (4) reduction of ZnO by inactivated Al. The experimental conditions and results observed by QMS were supported with literature data and physical measurement data from X-Ray Diffraction (XRD) which gave us an idea about the complex reaction cascade which occurred during the formation of the zinc metal. PY - 2010 U6 - https://doi.org/10.1039/c0ay00057d SN - 1759-9660 SN - 1759-9679 VL - 2 SP - 451 EP - 454 PB - RSC Publ. CY - Cambridge AN - OPUS4-21291 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Walter, Astrid A1 - Pfeifer, Dietmar A1 - Kraus, Werner A1 - Emmerling, Franziska A1 - Schneider, Rudolf A1 - Panne, Ulrich A1 - Weller, Michael G. T1 - Triacetone Triperoxide (TATP): Hapten design and development of antibodies N2 - Triacetone triperoxide (TATP), an improvised explosive, is a potential security threat because of its cost-efficient synthesis and the difficulty in detecting it. A highly selective antibody could provide the necessary specificity to the detection process. To obtain antibodies, a hapten made from acetone, hydrogen peroxide, and 7-oxooctanoic acid has been designed, synthesized, and confirmed by NMR that displays the utmost similarity to the analyte. The single-crystal X-ray structures of the solvated species TATP·methanol (1:1) and the TATP derivate were determined. In both compounds, the molecules exhibit D3 symmetry and adopt a twisted boat-chair conformation. The hapten was coupled to bovine serum albumin, and mice were immunized. An immune response against TATP was elicited, and selective antibodies were detected in the mouse serum, which should be very useful for the development of a TATP biosensor system. An ELISA with a limit of detection for TATP of 65 µg L-1 is shown. KW - TATP KW - Triacetone triperoxide KW - Explosive KW - Antibody KW - Hapten immunoassay KW - Structure PY - 2010 U6 - https://doi.org/10.1021/la1018339 SN - 0743-7463 SN - 1520-5827 VL - 26 IS - 19 SP - 15418 EP - 15423 PB - American Chemical Society CY - Washington, DC AN - OPUS4-22469 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Leiterer, Jork A1 - Emmerling, Franziska A1 - Panne, Ulrich A1 - Christen, W. A1 - Rademann, K. T1 - Tracing Coffee Tabletop Traces N2 - Crystallization processes under different conditions are of fundamental interest in chemistry, pharmacy, and medicine. Therefore, we have studied the formation of micro- and nanosized crystals using water-caffeine (1,3,7-trimethyl-1H-purine-2,6(3H,7H)-dione) solutions under ambient conditions as a relevant model system. When droplets of an aqueous caffeine solution evaporate and eventually dry on surfaces (glass, polystyrene, and polyester), stable “coffee tabletop” rings with a perimeter of typically 3 mm are formed after 20 to 50 min. Using a micro focus X-ray beam available at the BESSY µSpot-beamline, the fine structure of different caffeine needles can be distinguished. Unexpectedly, both crystal modifications (α- and β-caffeine) are present, but locally separated in these rings. Furthermore, AFM studies reveal the presence of even smaller particles on a nanometer length scale. To eliminate influences of surface irregularities from the crystallization process, acoustic levitation of liquid samples was employed. Such levitated droplets are trapped in a stable position and only surrounded by air. The solvent in an ultrasonically levitated drop evaporates completely, and the resulting crystallization of caffeine was followed in situ by synchrotron X-ray diffraction. In this case, the diffraction pattern is in accordance with pure α-caffeine and does not indicate the formation of the room temperature polymorph β-caffeine. Hence, our investigations open new vistas that may lead to a controlled formation of cocrystals and novel polymorphs of micro- and nanocrystalline materials, which are of relevance for fundamental studies as well as for pharmaceutical and medical applications. KW - Polymorphism KW - Crystallization KW - Acoustic levitation KW - Evaporation of droplets KW - µSpot KW - Micro spot KW - Synchrotron radiation PY - 2008 U6 - https://doi.org/10.1021/la800768v SN - 0743-7463 SN - 1520-5827 VL - 24 IS - 15 SP - 7970 EP - 7978 PB - American Chemical Society CY - Washington, DC AN - OPUS4-17818 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gornushkin, Igor B. A1 - Merk, Sven A1 - Demidov, Alexandr A1 - Panne, Ulrich A1 - Shabanov, Sergej V. A1 - Smith, B.W. A1 - Omenetto, N. T1 - Tomography of single and double pulse laser-induced plasma using Radon transform technique N2 - The Radon transform tomography is used for reconstruction of the emissivity distribution in single- (SP) and double-pulse (DP) laser induced plasmas in orthogonal geometry. The orthogonal DP plasma is intrinsically asymmetric and thus suitable for the Radon reconstruction. The DP plasma consists of two plasmas separated by a short time interval of ~ 1 µs. The first plasma is created in air near the surface of a Si wafer and is followed (pre-ablation mode) or preceded (post-ablation mode) by the second plasma induced on this surface. A spectrometer moves in a semi-circular path around the plasma keeping the plasma in the rotation center. The optical detection is arranged so that a thin plasma layer parallel to the target surface is monitored. The axial symmetry of the SP plasma is investigated by comparing data from the Abel inversion taken at different angles and Radon reconstruction. The multi-angle measurements are used to estimate errors of the Abel reconstruction due to asymmetries of the plasma. Time-resolved Radon reconstruction in white light is performed for the DP plasma in both pre- and post-ablation modes. In the former case, the effect of ablated aerosol on the formation of the air plasma is monitored. In the latter case, a formation of an asymmetric compression shock created by the target plasma inside the air plasma is visualized. This observation is supported by computer simulations. An interaction of the two plasmas is studied by spectrally resolved Radon reconstruction revealing a complex distribution of target and ambient species inside the plasma at all studied delay times. Overall, it is demonstrated that Radon-based tomography is an informative tool to study transient asymmetric laser induced plasmas. KW - Radon transform tomography of SP KW - DP laser induced plasma KW - LIBS KW - Orthogonal double pulse plasma PY - 2012 U6 - https://doi.org/10.1016/j.sab.2012.06.033 SN - 0584-8547 SN - 0038-6987 VL - 76 SP - 203 EP - 213 PB - Elsevier CY - Amsterdam AN - OPUS4-27438 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Eschlböck-Fuchs, S. A1 - Demidov, Alexander A1 - Gornushkin, Igor B. A1 - Schmid, Thomas A1 - Rössler, R. A1 - Huber, N. A1 - Panne, Ulrich A1 - Pedarnig, J. D. T1 - Tomography of homogenized laser-induced plasma by Radon transform technique N2 - Tomography of a laser-induced plasma in air is performed by inverse Radon transform of angle-resolved plasma images. Plasmas were induced by single laser pulses (SP), double pulses (DP) in collinear geometry, and by a combination of single laser pulses with pulsed arc discharges (SP-AD). Images of plasmas on metallurgical steel slags were taken at delay times suitable for calibration-free laser-induced breakdown spectroscopy (CFLIBS). Delays ranged from few microseconds for SP and DP up to tens of microseconds for SP-AD excitation. The white-light and the spectrally resolved emissivity ε(x,y,z) was reconstructed for the three plasma excitation schemes. The electron number density Ne(x,y,z) and plasma temperature Te(x,y,z) were determined from Mg and Mn emission lines in reconstructed spectra employing the Saha-Boltzmann plot method. The SP plasma revealed strongly inhomogeneous emissivity and plasma temperature. Re-excitation of plasma by a second laser pulse (DP) and by an arc discharge (SP-AD) homogenized the plasma and reduced the spatial variation of ε and Te. The homogenization of a plasma is a promising approach to increase the accuracy of calibration-free LIBS analysis of complex materials. KW - Plasma tomography KW - Laser induced plasma KW - Radon transform technique KW - Laser induced breakdown spectroscopy (LIBS) KW - Steel slag KW - Calibration-free analysis PY - 2016 U6 - https://doi.org/10.1016/j.sab.2016.07.007 VL - 123 SP - 59 EP - 67 PB - Elsevier B.V. AN - OPUS4-37452 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Leiterer, Jork A1 - Leitenberger, W. A1 - Emmerling, Franziska A1 - Thünemann, Andreas A1 - Panne, Ulrich T1 - The use of an acoustic levitator to follow crystallization in small droplets by energy-dispersive X-ray diffraction N2 - For the investigation of small sample volumes, the use of an acoustic levitator was tested as a `sample holder' for hovering droplets in a synchrotron beam. It might be advantageous to use levitated droplets instead of samples confined in solid holders, especially for the study of crystallization processes where the influence of containing walls has to be minimized. In a first experiment, the crystallization of sodium chloride in a small droplet of aqueous solution has been followed with a time resolution of 30 s. The collected diffraction peaks are compared with data in the ICSD database. KW - EDXD KW - Noncontact measurement technique KW - X-ray-scattering KW - Synchrotron-radiation KW - Acoustic levitation PY - 2006 U6 - https://doi.org/10.1107/S0021889806024915 SN - 0021-8898 SN - 1600-5767 VL - 39 IS - 5 SP - 771 EP - 773 PB - Blackwell CY - Oxford AN - OPUS4-13516 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - García-Fernández, J. A1 - Bettmer, J. A1 - Jakubowski, Norbert A1 - Panne, Ulrich A1 - Añón, E. A1 - Montes-Bayón, M. A1 - Sanz-Medel, A. T1 - The fate of iron nanoparticles used for treatment of iron deficiency in blood using mass-spectrometry based strategies N2 - The release of iron from iron nanoparticles (NPs) used as parenteral formulations appears to be influenced by the size and surface properties of the colloidal iron complex and the matrix. A clinically applied product Venofer® has been used as a model formulation to establish adequate analytical strategies to evaluate the fate of iron nanoparticles (NPs) in blood. First, the preparation was characterized by high resolution transmission electron microscopy (HRTEM), dynamic light scattering (DLS) and UV-vis absorption spectroscopy. This revealed the presence of monodisperse iron NPs with a hydrodynamic diameter of ∼15 nm and an iron core of ∼4 nm. Venofer® was then incubated with serum and whole blood in a quantitative study on the iron bioavailability from these NPs. Iron was speciated and quantified by using inductively coupled plasma mass spectrometry (ICP-MS). Iron solubilization levels of up to 42% were found in both fluids using isotope dilution of iron for quantification within the first hour of incubation even in the absence of the reticuloendothelial system. The monitoring of the iron-containing proteins present in serum was conducted by highperformance liquid chromatography with ICP-MS detection. It indicated that the dissolved iron ions are bound to transferrin. Quantitative speciation studies using isotope pattern deconvolution experiments concluded that the released iron saturated almost completely (up to 90%) the metal binding sites of transferrin. The remaining iron appeared also associated to albumin and, to a lesser extent, forming smaller sized particles. Thus, the methods presented here provide new insights into the fate of Venofer® nanoparticles and may be applied to other formulations. KW - Iron-sucrose nanoparticles KW - Serum KW - Bioavailability KW - Speciation KW - HPLC KW - ICP-MS PY - 2017 U6 - https://doi.org/10.1007/s00604-017-2388-8 SN - 0026-3672 SN - 1436-5073 VL - 184 IS - 10 SP - 3673 EP - 3680 AN - OPUS4-43128 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Shelby, D. A1 - Merk, Sven A1 - Smith, B.W. A1 - Gornushkin, Igor B. A1 - Panne, Ulrich A1 - Omenetto, N. T1 - Temperature evaluation by simultaneous emission and saturated fluorescence measurements: A critical theoretical and experimental appraisal of the approach N2 - Temperature is one of the most important physical parameters of plasmas induced by a focused laser beam on solid targets, and its experimental evaluation has received considerable attention. An intriguing approach, first proposed by Kunze (H.-J. Kunze, Experimental check of local thermodynamic equilibrium in discharges, Appl. Opt., 25 (1986) 13–13.) as a check of the existence of local thermodynamic equilibrium, is based upon the simultaneous measurement of the thermal emission and the optically saturated fluorescence of the same selected atomic transition. The approach, whose appealing feature is that neither the calibration of the set-up nor the spontaneous radiative probability of the transitions is needed, has not yet been applied, to our knowledge, to analytical flames and plasmas. A critical discussion of the basic requirements for the application of the method, its advantages, and its experimental limitations, is therefore presented here. For our study, Ba+ transitions in a plasma formed by focusing a pulsed Nd:YAG laser (1064 nm) on a glass sample containing BaO are selected. At various delay times from the plasma initiation, a pulsed, excimer-pumped dye laser tuned at the center of two Ba transitions (6s ²S1/2 → 6p ²P°3/2; 455.403 nm and 6p ²P°1/2 → 6d ²S1/2; 452.493 nm) is used to enhance the populations of the excited levels (6p ²P°3/2 and 6d ²S1/2) above their thermal values. The measured ratio of the emission and direct line fluorescence signals observed at 614.171 nm (6p ²P°3/2 → 5d ²D5/2) and 489.997 nm (6d ²S1/2 → 6p ²P°3/2) is then related to the excitation temperature of the plasma. Our conclusion is that the approach, despite being indeed attractive and clever, does not seem to be easily applicable to flames and plasmas, in particular to transient and inhomogeneous plasmas such as those induced by lasers on solids. KW - Plasma temperature KW - Optically saturated fluorescence KW - Laser induced plasma KW - Barium ion emission KW - Emission/fluorescence ratio PY - 2013 U6 - https://doi.org/10.1016/j.sab.2013.09.002 SN - 0584-8547 SN - 0038-6987 VL - 89 SP - 50 EP - 59 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-30436 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Seifert, Stephan A1 - Weidner, Steffen A1 - Panne, Ulrich A1 - Kneipp, Janina T1 - Taxonomic relationship of pollen from MALDI TOF MS data using multivariate statistics N2 - Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been suggested as a promising tool for the investigation of pollen, but the usefulness of this approach for classification and identification of pollen species has to be proven by an application to samples of varying taxonomic relations. KW - MALDI mass spectrometry KW - Pollen KW - Multivariate statistics PY - 2015 U6 - https://doi.org/10.1002/rcm.7207 SN - 0951-4198 SN - 1097-0231 VL - 29 SP - 1145 EP - 1154 PB - Wiley CY - Chichester AN - OPUS4-35296 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nadejde, C. A1 - Neamtu, M. A1 - Hodoroaba, Vasile-Dan A1 - Schneider, Rudolf A1 - Paul, Andrea A1 - Ababei, G. A1 - Panne, Ulrich T1 - Tannic acid- and natural organic matter-coated magnetite as green Fenton-like catalysts for the removal of water pollutants N2 - The use of magnetic materials as heterogeneous catalysts has attracted increasing attention in the last years since they proved to be promising candidates for water treatment. In the present study, two types of surface-modified magnetite (Fe3O4) nanoparticles, coated with non-hazardous naturally occurring agents—either tannic acid (TA) or dissolved natural organic matter—were evaluated as magnetic heterogeneous catalysts. Chemical synthesis (co-precipitation) was chosen to yield the nanocatalysts due to its well-established simplicity and efficiency. Subsequently, the properties of the final products were fully assessed by various characterization techniques. The catalytic activity in heterogeneous oxidation of aqueous solutions containing a model pollutant, Bisphenol A (BPA), was comparatively studied. The effect of operational parameters (catalyst loading, H2O2 dosage, and UV light irradiation) on the Degradation performance of the oxidation process was investigated. The optimum experimental parameters were found to be 1.0 g/L of catalysts and 10 mM H2O2, under UV irradiation. The highest mineralization rates were observed for Fe3O4-TA catalyst. More than 80 % of BPA was removed after 30 min of reaction time under the specified experimental conditions. The obtained results showed that the two catalysts studied here are suitable candidates for the removal of pollutants in wastewaters by means of heterogeneous reaction using a green sustainable treatment method. KW - Nanocatalysts KW - Photo-Fenton oxidation KW - Wastewater KW - Bisphenol A degradation KW - Environment KW - Mitigation PY - 2015 UR - http://link.springer.com/article/10.1007/s11051-015-3290-0 U6 - https://doi.org/10.1007/s11051-015-3290-0 VL - 17 IS - 12 SP - 476 (1) EP - 476 (10) PB - Springer AN - OPUS4-38758 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hachenberger, Y. U. A1 - Rosenkranz, D. A1 - Kriegel, Fabian L. A1 - Krause, B. A1 - Matschaß, René A1 - Reichardt, P. A1 - Tentschert, J. A1 - Laux, P. A1 - Jakubowski, Norbert A1 - Panne, Ulrich A1 - Luch, A. T1 - Tackling Complex Analytical Tasks: An ISO/TS-Based Validation Approach for Hydrodynamic Chromatography Single Particle Inductively Coupled Plasma Mass Spectrometry N2 - Nano-carrier systems such as liposomes have promising biomedical applications. Nevertheless, characterization of these complex samples is a challenging analytical task. In this study a coupled hydrodynamic chromatography-single particle-inductively coupled plasma mass spectrometry (HDC-spICP-MS) approach was validated based on the technical specification (TS) 19590:2017 of the international organization for standardization (ISO). The TS has been adapted to the hyphenated setup. The quality criteria (QC), e.g., linearity of the calibration, transport efficiency, were investigated. Furthermore, a cross calibration of the particle size was performed with values from dynamic light scattering (DLS) and transmission electron microscopy (TEM). Due to an additional Y-piece, an online-calibration routine was implemented. This approach allows the calibration of the ICP-MS during the dead time of the chromatography run, to reduce the required time and enhance the robustness of the results. The optimized method was tested with different gold nanoparticle (Au-NP) mixtures to investigate the characterization properties of HDC separations for samples with increasing complexity. Additionally, the technique was successfully applied to simultaneously determine both the hydrodynamic radius and the Au-NP content in liposomes. With the established hyphenated setup, it was possible to distinguish between different subpopulations with various NP loads and different hydrodynamic diameters inside the liposome carriers. KW - Single particle ICP-MS KW - Nanoparticle characterization KW - Nano-carrier KW - Iposomes KW - Hydrodynamic chromatography (HDC) KW - Validation PY - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-506609 VL - 13 IS - 6 SP - 1 EP - 14 CY - Basel, Switzerland AN - OPUS4-50660 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Merk, Virginia A1 - Schulte, Franziska A1 - Rooch, Heidemarie A1 - Feldmann, Ines A1 - Dörfel, Ilona A1 - Österle, Werner A1 - Panne, Ulrich A1 - Kneipp, Janina T1 - Surface-enhanced Raman scattering with silver nanostructures generated in situ in a sporopollenin biopolymer matrix N2 - Silver nanoparticles were generated based on citrate reduction in the ultrastructure of the sporopollenin biopolymer of Ambrosia artemisiifolia (ragweed) and Secale cereale (rye). The nanoparticles enable the acquisition of SERS spectra and thereby a vibrational characterization of the local molecular structure of sporopollenin. PY - 2011 U6 - https://doi.org/10.1039/c0cc05326k SN - 0022-4936 SN - 0009-241x SN - 1359-7345 SN - 1364-548x N1 - Geburtsname von Merk, Virginia: Joseph, V. - Birth name of Merk, Virginia: Joseph, V. VL - 47 IS - 11 SP - 3236 EP - 3238 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-23482 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nietzold, Carolin A1 - Dietrich, Paul A1 - Holzweber, M. A1 - Lippitz, Andreas A1 - Kamalakumar, A. A1 - Blanchard, V. A1 - Ivanov-Pankov, S. A1 - Weigel, W. A1 - Panne, Ulrich A1 - Unger, Wolfgang T1 - Surface chemical characterization of model glycan surfaces and shelf life studies of glycan microarrays using XPS, NEXAFS spectroscopy, ToF-SIMS and fluorescence scanning N2 - Biomedical applications, including functional biomaterials, carbohydrate-arrays, and glycan-based biosensors. The chemistry of glycan immobilization plays an essential role in the bioavailability and function of surface bound carbohydrate moieties. For biomedical applications the stability over time (shelf life) of glycan arrays is a crucial factor. Herein we report on approaches for surface and interface characterization relevant to the needs of production of glycan microarrays which were tested using model carbohydrate surfaces. For detailed characterization of glycan model surfaces we used a combination of X-ray photoelectron spectroscopy (XPS), near edge X-ray absorption fine structure spectroscopy (NEXAFS) and ToF SIMS which are complementary techniques of surface chemical analysis. Links to fluorescence spectroscopy often used for characterization in the microarray community were established as well. In detail, amine-reactive silicon oxide and glass surfaces were used for anchoring oligosaccharides with an amino linker. The amount of surface bound carbohydrates was estimated by X-ray photoelectron spectroscopy (XPS). Glycan immobilization was investigated using lectins, which are glycan-binding molecules. A shelf life study of model glycan microarrays on epoxy-coated glass surfaces was done over a period of 160 days under different storage conditions utilizing fluorescence, ToF-SIMS and XPS analysis. It was shown that glycan activity of the models used can be maintained at least for half a year of storage at 4 °C. KW - Glycan microarray KW - XPS KW - NEXAFS KW - ToF-SIMS KW - Fluorescence PY - 2018 UR - https://www.sciencedirect.com/science/article/pii/S0169433218320300?via%3Dihub U6 - https://doi.org/10.1016/j.apsusc.2018.07.133 SN - 0169-4332 SN - 1873-5584 VL - 459 SP - 860 EP - 873 PB - Elsevier B.V. AN - OPUS4-46212 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hoffmann, Holger A1 - Baldofski, Stefanie A1 - Hoffmann, Kristin A1 - Flemig, Sabine A1 - Silva, C. P. A1 - Esteves, V. I. A1 - Emmerling, Franziska A1 - Panne, Ulrich A1 - Schneider, Rudolf T1 - Structural considerations on the selectivity of an immunoassay for sulfamethoxazole N2 - Sulfamethoxazol (SMX),a sulfonamide, is a widely used bacteriostatic antibiotic and therefore a promising marker for the entry of anthropogenic Pollution in the environment. SMX is frequently found in wastewater and surface water. This study presents the production of high affinity and selective polyclonal antibodies for SMX and the development and Evaluation of a direct competitive enzyme-linked immunosorbent assay(ELISA)for the quantification of SMX in environmental watersamples. The crystal structures of the cross-reacting compounds sulfamethizole, N4-acetyl-SMX andsuccinimidyl-SMX were determined by x-ray diffraction aiming to explain their high cross-reactivity. These crystal structures are described for the first time. The quantification range of the ELISA is 0.82–63 µg/L. To verify our results, the SMX concentration in 20 environmental samples,including wastewater and surfacewater,was determined by ELISA and tandem mass spectrometry(MS/MS).A good Agreement of the measured SMX concentrations was found with average recoveries of 97–113%for the results of ELISA compared to LC-MS/MS. KW - X-Ray diffraction KW - Sulfamethoxazole KW - ELISA KW - LC-MS/MS PY - 2016 U6 - https://doi.org/10.1016/j.talanta.2016.05.049 SN - 0039-9140 SN - 1873-3573 IS - 158 SP - 198 EP - 207 PB - Elsevier B.V. CY - Amsterdam, Netherlands AN - OPUS4-36676 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hoffmann, Holger A1 - Baldofski, Stefanie A1 - Hoffmann, Kristin A1 - Flemig, Sabine A1 - Silva, C. P. A1 - Esteves, V. I. A1 - Emmerling, Franziska A1 - Panne, Ulrich A1 - Schneider, Rudolf T1 - Structural considerations on the selectivity of an immunoassay for sulfamethoxazole N2 - Sulfamethoxazol (SMX),a sulfonamide, is a widely used bacteriostatic antibiotic and therefore a promising marker for the entry of anthropogenic Pollution in the environment. SMX is frequently found in wastewater and surface water. This study presents the production of high affinity and selective polyclonal antibodies for SMX and the development and Evaluation of a direct competitive enzyme-linked immunosorbent assay(ELISA)for the quantification of SMX in environmental watersamples. The crystal structures of the cross-reacting compounds sulfamethizole, N4-acetyl-SMX andsuccinimidyl-SMX were determined by x-ray diffraction aiming to explain their high cross-reactivity. These crystal structures are described for the first time. The quantification range of the ELISA is 0.82–63 µg/L. To verify our results, the SMX concentration in 20 environmental samples,including wastewater and surfacewater,was determined by ELISA and tandem mass spectrometry(MS/MS).A good Agreement of the measured SMX concentrations was found with average recoveries of 97–113%for the results of ELISA compared to LC-MS/MS. KW - X-Ray diffraction KW - ELISA KW - LC-MS/MS KW - Sulfamethoxazole PY - 2016 U6 - https://doi.org/10.1016/j.talanta.2016.05.049 SN - 0039-9140 SN - 1873-3573 IS - 158 SP - 198 EP - 207 PB - Elsevier B.V. CY - Amsterdam, Netherlands AN - OPUS4-38530 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bremser, Wolfram A1 - Becker, Roland A1 - Kipphardt, Heinrich A1 - Lehnik-Habrink, Petra A1 - Panne, Ulrich A1 - Töpfer, Antje T1 - Stability testing in an integrated scheme N2 - ISO Guide 35 deals with RM stability issues and scrutinizes the evaluation of stability testing results under the assumption that either there is no trend at all (a rather rare situation), or any observed deterministic change is insignificant and thus can be neglected. However, market demands for reliable reference materials are obviously not limited to stable or at least seemingly stable materials. In many analytical applications, analytes and measurands under consideration are known, or at least suspected, to be unstable on time scales that may vary widely from measurand to measurand. The Federal Institute for Materials Research and Testing (BAM) has developed (and successfully uses) an integrated approach in its certification practice. The approach is based on an initial stability study and subsequent post-certification monitoring. Data evaluation is model-based and takes advantage of all information collected in the stability testing scheme(s). It thus allows one to deal with any kind of instability observed, to assess limiting time intervals at any stress condition in the range tested, to estimate a final expiry date for materials with detected instabilities or the maximum admissible re-testing interval for seemingly stable materials, and to assess maximum admissible stress loads during delivery of the material to the customer. The article describes (and exemplifies) typical study layout, the model selection, and the integrated data assessment. KW - Certified reference materials KW - Stability KW - Shelf life KW - Arrhenius model KW - ERM PY - 2006 U6 - https://doi.org/10.1007/s00769-006-0152-6 SN - 0949-1775 SN - 1432-0517 VL - 11 IS - 10 SP - 489 EP - 495 PB - Springer CY - Berlin AN - OPUS4-14063 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bauer, M. A1 - Remmler, D. A1 - Dallmann, A. A1 - Jakubowski, Norbert A1 - Börner, H. G. A1 - Panne, Ulrich A1 - Limberg, C. T1 - Specific Decoration of a Discrete Bismuth Oxido Cluster by Selected Peptides towards the Design of Metal Tags N2 - Metal tags find application in a multitude of biomedical systems and the combination with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) offers an opportunity for multiplexing. To lay the foundation for an increase of the signal intensities in such processes, we herein present a general approach for efficient functionalization of a well-defined metal oxido cluster [Bi6O4(OH)(4)(SO3CF3)(6)(CH3CN)(6)].2 CH3CN (1), which can be realized by selecting 7mer peptide sequences via combinatorial means from large one-bead one-compound peptide libraries. Selective cluster-binding peptide sequences (CBS) for 1 were discriminated from non-binders by treatment with H2S gas to form the reduction product Bi2S3, clearly visible to the naked eye. Interactions were further confirmed by NMR experiments. Extension of a binding peptide with a maleimide linker (Mal) introduces the possibility to covalently attach thiol-bearing moieties such as biological probes and for their analysis the presence of the cluster instead of mononuclear entities should lead to an increase of signal intensities in LA-ICP-MS measurements. To prove this, CBS-Mal was covalently bound onto thiol-presenting glass substrates, which then captured 1 effectively, so that LA-ICP-MS measurements demonstrated drastic signal amplification compared to single lanthanide tags. KW - Peptide library KW - Mass spectrometry KW - Laser ablation KW - Cluster KW - Bioconjugation PY - 2019 U6 - https://doi.org/10.1002/chem.201805234 SN - 0947-6539 VL - 25 IS - 3 SP - 759 EP - 763 PB - John Wiley & Sons, Inc. AN - OPUS4-47324 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lindner, Uwe A1 - Lingott, Jana A1 - Richter, Silke A1 - Jakubowski, Norbert A1 - Panne, Ulrich T1 - Speciation of gadolinium in surface water samples and plants by hydrophilic interaction chromatography hyphenated with inductively coupled plasma mass spectrometry N2 - Hydrophilic interaction chromatography (HILIC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) was optimized for speciation analysis of gadolinium-based contrast agents in environmental samples, in particular surface river waters and plants. Surface water samples from the Teltow channel, near Berlin, were investigated over a distance of 5 km downstream from the influx of a wastewater treatment plant. The total concentration of gadolinium increased significantly from 50 to 990 ngL-1 due to the influx of the contrast agents. After complete mixing with the river water, the concentration remained constant over a distance of at least 4 km. Two main substances [Dotarem® (Gd-DOTA) and Gadovist® (Gd-BT-DO3A)] have been identified in the river water using standards. A gadolinium-based contrast agent, possibly Gd-DOTA (Dotarem®), was also detected in water plant samples taken from the Teltow channel. Therefore, uptake of contrast agents [Gadovist® (Gd-BTDO3A), Magnevist® (Gd-DTPA), Omniscan® (Gd-DTPA-BMA), Dotarem® (Gd-DOTA), and Multihance® (Gd-BOPTA)] by plants was investigated in a model experiment using Lepidium sativum (cress plants). HILIC–ICP-MS was used for identification of different contrast agents, and a first approach for quantification using aqueous standard solutions was tested. For speciation analysis, all investigated contrast agents could be extracted from the plant tissues with a recovery of about 54 % for Multihance® (Gd-BOPTA) up to 106 % for Gadovist® (Gd-BT-DO3A). These experiments demonstrate that all contrast agents investigated are transported from the roots to the leaves where the highest content was measured. KW - Gadolinium-based contrast agents KW - Hydrophilic interaction chromatography (HILIC) KW - Speciation KW - Inductively coupled plasma mass spectrometry (ICP-MS) KW - Plants KW - Surface water PY - 2013 U6 - https://doi.org/10.1007/s00216-012-6643-x SN - 1618-2642 SN - 1618-2650 VL - 405 IS - 6 SP - 1865 EP - 1873 PB - Springer CY - Berlin AN - OPUS4-27929 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chinthalapati, Siva Kesava Raju A1 - Cossmer, Antje A1 - Scharf, Holger A1 - Panne, Ulrich A1 - Lück, Detlef T1 - Speciation of gadolinium based MRI contrast agents in environmental water samples using hydrophilic interaction chromatography hyphenated with inductively coupled plasma mass spectrometry KW - HPLC-ICP-MS KW - HILIC chromatography KW - Speciation KW - Gadolinium KW - MRI contrast agent PY - 2010 U6 - https://doi.org/10.1039/b919959d SN - 0267-9477 SN - 1364-5544 VL - 25 SP - 55 EP - 61 PB - Royal Society of Chemistry CY - London AN - OPUS4-20705 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schlegel, Moritz-Caspar A1 - Müller, Urs A1 - Malaga, Katarina A1 - Panne, Ulrich A1 - Emmerling, Franziska T1 - Spatially resolved investigation of complex multi-phase systems using muXRF, SEM-EDX and high resolution SyXRD N2 - Spatially resolved analysis of complex multi-phase systems can be validated through different analytical methods. This study compares investigations by scanning electron microscopy coupled with energy dispersive X-ray fluorescence analysis and high resolution X-ray diffraction. The studied sulfate attacked cement paste containing fly ashes consists of different interacting crystalline and amorphous phases. The complementary methods revealed in detail changes in phase composition due to the chemical attack. The advantages and disadvantages of both methods are discussed and suggestions are given for combining them with additional methods to maximize the information content. KW - EDX-SEM KW - SyXRD KW - Spatial investigations KW - Comparison KW - High resolution KW - Cement paste KW - Sulfate attack KW - Damaging mechanism PY - 2013 U6 - https://doi.org/10.1016/j.cemconcomp.2012.08.018 SN - 0958-9465 SN - 1873-393X VL - 37 SP - 241 EP - 245 PB - Elsevier Ltd. CY - Barking, Essex AN - OPUS4-29111 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neamtu, M. A1 - Nadejde, C. A1 - Hodoroaba, Vasile-Dan A1 - Schneider, Rudolf A1 - Panne, Ulrich T1 - Singlet oxygen generation potential of porphyrin-sensitized magnetite nanoparticles: Synthesis, characterization and photocatalytic application N2 - Singlet oxygen generation potential of two novel free-base-porphyrin photocatalysts was investigated. The freebase-porphyrin-sensitized Fe3O4 magnetic nanoparticles (MNPs) were tested for the degradation of the model pollutant Bisphenol A (BPA) in aqueous solution, for the first time. MNPs with either cubic or spherical shape were synthesized using the sonochemical approach, followed by sensitizing with photoactive 4,4′,4′′,4′′′- (Porphine-5,10,15,20-tetrayl)tetrakis(benzoic acid) (TCPP). The resulted photocatalysts were characterized in detail by scanning and transmission electron microscopy, Brunauer–Emmett–Teller analysis, spectral techniques and vibrating sample magnetometry. The electron spin resonance experiments have confirmed the high activity of the photocatalysts through the efficient formation of singlet oxygen in solution. The optimum operational parameters for BPA degradation were established as follows: 1.0 μmol L−1 BPA, 1.0 g L−1 of photocatalyst, 100 μmol L−1 H2O2, under UVA irradiation. In these conditions, the results for both photocatalysts revealed that after only 10 min of reaction, over 64% and ca. 90% of BPA have been removed from solution in the absence and presence of H2O2, respectively. Whereas after 60 minutes of treatment, only 24% of BPA in real wastewater effluent samples were removed under UVA irradiation in the absence of H2O2, showing the high complexity of real wastewater. Moreover, both photocatalysts were successfully used for BPA removal in three consecutive runs, without significant loss of catalytic features. KW - Bisphenol A KW - Magnetpartikel KW - Photooxidation KW - Singulettsauerstoff KW - TEM KW - SEM KW - Brunauer-Emmett-Teller KW - Katalysator KW - Abwasser KW - ESR PY - 2018 U6 - https://doi.org/10.1016/j.apcatb.2018.03.079 SN - 0926-3373 VL - 232 SP - 553 EP - 561 PB - Elsevier B.V. CY - Amsterdam, NL AN - OPUS4-45267 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schenk, Jonas A1 - Batzdorf, Lisa A1 - Emmerling, Franziska A1 - Kneipp, Janina A1 - Panne, Ulrich A1 - Buurman, Merwe T1 - Simultaneous UV/Vis spectroscopy and surface enhanced raman scattering of nanoparticle formation and aggregation in levitated droplets N2 - The formation and growth of hydroxylamine reduced silver nanoparticles were investigated by simultaneous Raman and UV/Vis spectroscopy coupled to an acoustic levitator as a sample holder. Based on the UV/Vis spectra, a two step particle formation mechanism with fast initial formation and adjacent coalescence can be proposed for the reduction of silver nitrate with hydroxylamine. The presence of the analyte adenine during particle formation resulted in differences in the adenine SERS signature compared to experiments, where adenine was added after particle synthesis. It was possible to monitor the adenine and sodium chloride induced aggregation of the nanoparticles and its dynamics based on both the extinction spectra and the SERS data. Correlating the information from the extinction spectra with the SERS intensity, the maximum SERS signals were observed at maximum extinction of the aggregated nanoparticle solution at the Raman excitation wavelength. PY - 2012 U6 - https://doi.org/10.1039/c2ay05744a SN - 1759-9660 SN - 1759-9679 N1 - Geburtsname von Batzdorf, Lisa: Tröbs, L. - Birth name of Batzdorf, Lisa: Tröbs, L. N1 - Geburtsname von Buurman, Merwe: Albrecht, M. - Birth name of Buurman, Merwe: Albrecht, M. VL - 4 IS - 5 SP - 1252 EP - 1258 PB - RSC Publ. CY - Cambridge AN - OPUS4-25742 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Epping, Ruben A1 - Falkenhagen, Jana A1 - Panne, Ulrich A1 - Hiller, W. A1 - Gruendling, T. A1 - Staal, B. A1 - Lang, C. A1 - Lamprou, A. T1 - Simultaneous characterization of poly(acrylic acid) andpolysaccharide polymers and copolymers N2 - Copolymer products that result from grafting acrylic acid and other hydrophilicmonomers onto polysaccharides have recently gained significant interest in researchand industry. Originating from renewable sources, these biodegradable, low toxicity,and polar copolymer products exhibit potential to replace polymers from fossil sourcesin several applications and industries. The methods usually employed to character-ize these copolymers are, however, quite limited, especially for the measurement ofbulk properties. With more sophisticated applications, for example, in pharmaceu-tics requiring a more detailed analysis of the chemical structure, we describe a newapproach for this kind of complex polymers. Our approach utilizes chromatographyin combination with several detection methods to separate and characterize reactionproducts of the copolymerization of acrylic acid and chemically hydrolyzed starch.These samples consisted of a mixture of homopolymer poly (acrylic acid), homopoly-mer hydrolyzed starch, and – in a lower amount – the formed copolymers. Several chro-matographic methods exist that are capable of characterizing either poly (acrylic acid)or hydrolyzed starch. In contrast, our approach offers simultaneous characterization ofboth polymers. The combination of LC and UV/RI offered insight into the compositionand copolymer content of the samples. Size exclusion chromatography experimentsrevealed the molar mass distribution of homopolymers and copolymers. FTIR inves-tigations confirmed the formation of copolymers while ESI-MS gave more details onthe end groups of hydrolyzed starches and poly (acrylic acids). Evidence of copolymerstructures was obtained through NMR measurements. Finally, two-dimensional chro-matography led to the separation of the copolymers from both homopolymers as wellas the additional separation of sodium clusters. The methods described in this work area powerful toolset to characterize copolymerization products of hydrolyzed starch andpoly(acrylic acid). Together, our approach successfully correlates the physicochemicalproperties of such complex mixtures with their actual composition. KW - 2D chromatography KW - LC-MS KW - SEC KW - Renewable copolymers KW - Grafting PY - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-508873 SP - 1 EP - 12 PB - Wiley-VCH Verlag-GmbH&Co. KGaA CY - Weinheim AN - OPUS4-50887 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Phukphatthanachai, Pranee A1 - Panne, Ulrich A1 - Jakubowski, Norbert A1 - Vogl, Jochen T1 - SI-traceable quantification of sulphur in copper metal and its alloys by ICP-IDMS N2 - Previously applied methods for the quantification of sulphur in copper and other pure metals revealed a lack of SI-traceability and additionally showed inconsistent results, when different methods were compared. Therefore, a reference procedure is required which allows SI-traceable values accompanied by a Sound uncertainty budget. In this study a procedure was developed for the quantification of total sulphur in copper at low concentration levels using inductively coupled plasma-isotope dilution mass spectrometry (ICP-IDMS). The major part of the copper matrix was separated by adding ammonia which forms a complex with the copper while releasing the sulphur followed by chromatographic separation using a weak cation resin. After that the sulphur fraction was further purified by chromatographic means using first an anion exchange method and second a chelating resin. The developed procedure shows high performance, especially concerning high efficiency in matrix removal (>99.999%) while keeping the recovery of sulphur above 80%. Procedure blanks are in the order of 3–53 ng resulting in LOD and LOQ values of 0.2 mg g1 and 0.54 mg g1, respectively. The procedure is sufficient to facilitate value assignment of the total sulphur mass fraction in reference materials. Additionally, relative measurement uncertainties were calculated to be below 1% and the measurement results were traceable to the SI. The procedure reported in this study is a new reference procedure for sulphur measurement in copper, being fit for two major purposes, certification of reference materials and assignment of reference values for inter-laboratory comparison. KW - Traceability KW - Measuremment uncertainty KW - Isotope dilution mass spectrometry KW - Reference measurements PY - 2018 U6 - https://doi.org/10.1039/c7ja00338b SN - 0267-9477 SN - 1364-5544 VL - 33 IS - 1 SP - 90 EP - 101 PB - Royal Society of Chemistry CY - Cambridge, UK AN - OPUS4-43614 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Abad Andrade, Carlos Enrique A1 - Florek, S. A1 - Becker-Ross, H. A1 - Huang, M.-D. A1 - Lopez-Linares, F. A1 - Poirier, L. A1 - Jakubowski, Norbert A1 - Recknagel, Sebastian A1 - Panne, Ulrich T1 - Shake, shut, and go – A fast screening of sulfur in heavy crude oils by highresolution continuum source graphite furnace molecular absorption spectrometry via GeS molecule detection N2 - A fast and simple method for sulfur quantification in crude oils was developed by using high-resolution continuum source graphite furnace molecular absorption spectrometry (HR-CS-GFMAS). For this, heavy crude oil samples were prepared as microemulsion (shake) and injected into a graphite furnace (shut). Finally, the concentration of sulfur was determined by monitoring in situ the transient molecular spectrum of GeS at wavelength 295.205nm after adding a germanium solution as molecular forming agent (and go). Zirconium dioxide in the form of nanoparticles (45–55nm) was employed as a permanent modifier of the graphite furnace. Calibration was done with an aqueous solution standard of ammonium sulfate, and a characteristic mass (m0) of 7.5ng was achieved. The effectiveness of the proposed method was evaluated analizing, ten heavy crude oil samples with Sulfur amounts ranging between 0.3 and 4.5% as well as two NIST standard reference materials, 1620c and 1622e. Results were compared with those obtained by routine ICP-OES analysis, and no statistical relevant differences were found. KW - Heavy crude oil KW - Sulfur KW - HR-CS-MAS KW - Germanium sulfide KW - Microemulsion PY - 2019 U6 - https://doi.org/10.1016/j.sab.2019.105671 SN - 0584-8547 VL - 160 SP - 105671 PB - Elsevier B.V. CY - Amsterdam, Netherlands AN - OPUS4-48747 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Eichelbaum, M. A1 - Kneipp, Janina A1 - Schmidt, B.E. A1 - Panne, Ulrich A1 - Rademann, K. T1 - SERS and Multiphoton-Induced Luminescence of Gold Micro- and Nanostructures Fabricated by NIR Femtosecond-Laser Irradiation KW - Gold KW - Luminescence KW - Multiphoton fabrication KW - Sol-gel processes KW - Surface-enhanced Raman scattering PY - 2008 U6 - https://doi.org/10.1002/cphc.200800417 SN - 1439-4235 SN - 1439-7641 VL - 9 IS - 15 SP - 2163 EP - 2167 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-18233 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - You, Zengchao A1 - Jakubowski, Norbert A1 - Panne, Ulrich A1 - Weidner, Steffen T1 - Separation of polystyrene nanoparticles with different coatings using two-dimensional off-line coupling of asymmetrical flow field flow fractionation and capillary electrophoresis N2 - The successful off-line coupling of asymmetrical flow field flow fractionation (AF4) and capillary electrophoresis (CE) for separation of nanoparticles (NPs) with different surface coatings was shown. We could successfully demonstrate that, in a certain NP size range, hyphenation of both techniques significantly improved the separation of differently coated NPs. Three mixtures of polystyrene nanoparticles (PS-NPs) with comparable core sizes but different coatings (no coating/carboxyl-coated) were studied. Separation in either method resulted in non-baseline resolved or non-separated peaks. In contrast, two-dimensional off-line coupling of AF4 and CE resulted in clearly separated regions in their 2 D plots in case of 20 and 50 nm particle mixtures, whereas the 100 nm NP mixture could not be separated at all. Various factors affecting the separation like hydrodynamic diameter or SDS concentration were discussed. KW - Capillary electrophoresis (CE) KW - Nanoparticles with same nominal diameter KW - Surface coating KW - Two-dimensional off-line coupling KW - Asymmetrical flow field flow fractionation (AF4) PY - 2019 U6 - https://doi.org/10.1016/j.chroma.2019.01.056 VL - 1593 SP - 119 EP - 126 PB - Elsevier AN - OPUS4-47363 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - You, Zengchao A1 - Nirmalananthan-Budau, Nithiya A1 - Resch-Genger, Ute A1 - Panne, Ulrich A1 - Weidner, Steffen T1 - Separation of polystyrene nanoparticles bearing different carboxyl group densities and functional groups quantification with capillary electrophoresis and asymmetrical flow field flow fractionation N2 - Two sets of polystyrene nanoparticles (PSNPs) with comparable core sizes but different carboxyl group densities were made and separated using asymmetric flow field flow fractionation (AF4), capillary electrophoresis (CE), and the off-line hyphenation of both methods. Our results revealed the significant potential of two-dimensional off-line AF4-CE hyphenation to improve the separation and demonstrated for the first time, the applicability of CE to determine the functional group density of nanoparticles (NPs). Compared to the result acquired with conductometric titration, the result obtained with synthesized 100 nm sized PSNPs revealed only a slight deviation of 1.7%. Commercial 100 nm sized PSNPs yielded a deviation of 4.6 %. For 60 nm sized PSNPs, a larger deviation of 10.6 % between both methods was observed, which is attributed to the lower separation resolution. KW - Nanoparticle KW - A4F KW - Capillary electrophoresis KW - Carboxyl group PY - 2020 U6 - https://doi.org/10.1016/j.chroma.2020.461392 VL - 1626 SP - 461392 PB - Elsevier B.V. AN - OPUS4-51080 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sötebier, Carina A. A1 - Weidner, Steffen A1 - Jakubowski, Norbert A1 - Panne, Ulrich A1 - Bettmer, J. T1 - Separation and quantification of silver nanoparticles and silver ions using reversed phase high performance liquid chromatography coupled to inductively coupled plasma mass spectrometry in combination with isotope dilution analysis N2 - A reversed phase high performance liquid chromatography coupled to an inductively coupled Plasma mass spectrometer (HPLC–ICP-MS) approach in combination with isotope dilution analysis (IDA) for the separation and parallel quantification of nanostructured and ionic silver (Ag) is presented. The main Focus of this work was the determination of the ionic Ag concentration. For a sufficient stabilization of the Ions without dissolving the nanoparticles (NPs), the eluent had to be initially optimized. The determined Ag ion concentration was in a good agreement with results obtained using ultrafiltration. Further, the mechanism of the NP separation in the HPLC column was investigated. Typical size exclusion effects were found by comparing results from columns with different pore sizes. Since the recovery rates decreased with increasing Ag NP size and large Ag NPs did not elute from the column, additional interactions of the particles with the stationary phase were assumed. Our results reveal that the presented method is not only applicable to Ag NPs, but also to gold and polystyrene NPs. Finally, IDA-HPLC-ICP-MS experiments in single particle mode were performed to determine the particle cut-off size. The comparison with conventional spICP-MS experiments resulted in a similar diameter and particle size distribution. KW - ICP-MS KW - Silver nanoparticles KW - Speciation KW - High performance liquid chromatography KW - Isotope dilution analysis PY - 2016 U6 - https://doi.org/10.1016/j.chroma.2016.09.028 SN - 0021-9673 VL - 1468 SP - 102 EP - 108 AN - OPUS4-37652 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sötebier, Carina A1 - Weidner, Steffen A1 - Jakubowski, Norbert A1 - Panne, Ulrich A1 - Bettmer, J. T1 - Separation and quantification of silver nanoparticles and silver ions using reversed phase high performance liquid chromatography coupled to inductively coupled plasma mass spectrometry in combination with isotope dilution analysis N2 - A reversed phase high performance liquid chromatography coupled to an inductively coupled plasma mass spectrometer (HPLC-ICP-MS) approach in combination with isotope dilution analysis (IDA) for the separation and parallel quantification of nanostructured and ionic silver (Ag) is presented. The main focus of this work was the determination of the ionic Ag concentration. For a sufficient stabilization of the ions without dissolving the nanoparticles (NPs), the eluent had to be initially optimized. The determined Ag ion concentration was in a good agreement with results obtained using ultrafiltration. Further, the mechanism of the NP separation in the HPLC column was investigated. Typical size exclusion effects were found by comparing results from columns with different pore sizes. Since the recovery rates decreased with increasing Ag NP size and large Ag NPs did not elute from the column, additional interactions of the particles with the stationary phase were assumed. Our results reveal that the presented method is not only applicable to Ag NPs, but also to gold and polystyrene NPs. Finally, IDA-HPLC-ICP-MS experiments in single particle mode were performed to determine the particle cut-off size. The comparison with conventional spICP-MS experiments resulted in a similar diameter and particle size distribution. KW - ICP-MS KW - Silver nanoparticles KW - HPLC KW - Isotope dilution analysis KW - Field flow fractionation KW - Toxicology PY - 2016 U6 - https://doi.org/10.1016/j.chroma.2016.09.028 SN - 0021-9673 VL - 1468 SP - 102 EP - 108 PB - Elsevier B.V. AN - OPUS4-38642 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Abdelshafi, Nahla A. A1 - Panne, Ulrich A1 - Schneider, Rudolf T1 - Screening for cocaine on Euro banknotes by a highly sensitive enzyme immunoassay N2 - This study focused on quantitative detection of cocaine on Euro banknotes in Germany. A sensitive direct competitive immunoassay was developed and optimized with a limit of detection (LOD) of 5.6 ng/L. Exhaustive cocaine extraction by solvent was tested using different methanol concentrations and buffered solutions. Crossreactivity studies were performed to determine the degree of interference of cocaine metabolites with the immunoassay. Sixty-five Euro banknotes obtained from different districts in Berlin were evaluated. A 100% contamination frequency with cocaine was detected. A comparison between the amount of cocaine extracted by cotton swabbing of one square centimeter of the banknote showed a good correlation for lower contamination levels. This assay showed high sensitivity of detecting pg of cocaine per 1 cm2 of one banknote by swabbing 1 cm2: 0, 14, and 21 pg/cm2. Moreover, three notes of different denominations revealed high cocaine concentration; 1.1 mg/note, and twice 55 μg/note. KW - Cocaine KW - Euro banknotes KW - Drugs on bills KW - Enzyme-Linked Immunosorbent Assay KW - ELISA PY - 2017 U6 - https://doi.org/10.1016/j.talanta.2017.01.004 SN - 0039-9140 SN - 1873-3573 VL - 165 SP - 619 EP - 624 PB - Elsevier AN - OPUS4-39150 LA - eng 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 - Shigeta, K. A1 - Koellensperger, G. A1 - Rampler, E. A1 - Traub, Heike A1 - Rottmann, L. A1 - Panne, Ulrich A1 - Okino, A. A1 - Jakubowski, Norbert T1 - Sample introduction of single selenized yeast cells (Saccharomyces cerevisiae) by micro droplet generation into an ICP-sector field mass spectrometer for label-free detection of trace elements N2 - We have applied a micro droplet generator (µDG) for sample introduction of single selenized yeast cells into a sector field ICP-MS, which was operated in a fast scanning mode with sampling rates of up to 10 kHz, to measure single cells time resolved with 100 µs integration time. Selenized yeast cells have been used as a model system for preliminary investigation. The single cells to be measured have been embedded into droplets and it will be shown that the time duration of a single cell event always is about 400 to 500 µs, and thus comparable to the time duration of a droplet without a cell. A fixed droplet generation rate of 50 Hz produced equidistant signals in time of each droplet event and was advantageous to separate contribution from background and blank from the analytical signal. Open vessel digestion and a multielement analysis were performed with washed yeast cells and absolute amounts per single cell were determined for Na (0.91 fg), Mg (9.4 fg), Fe (5.9 fg), Cu (0.54 fg), Zn (1.2 fg) and Se (72 fg). Signal intensities from single cells have been measured for the elements Cu, Zn and Se, and histograms were calculated for about 1000 cell events. The mean elemental sensitivities measured here range from 0.7 counts per ag (Se) to 10 counts per ag (Zn) with RSD's from 49% (Zn) to 69% (Se) for about 1000 cell events. PY - 2013 U6 - https://doi.org/10.1039/c3ja30370e SN - 0267-9477 SN - 1364-5544 VL - 28 IS - 5 SP - 637 EP - 645 PB - Royal Society of Chemistry CY - London AN - OPUS4-29448 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neamtu, M. A1 - Macaev, F. A1 - Boldescu, V. A1 - Hodoroaba, Vasile-Dan A1 - Nadejde, C. A1 - Schneider, Rudolf A1 - Paul, Andrea A1 - Ababei, G. A1 - Panne, Ulrich T1 - Removal of pollutants by the new Fenton-like highly active catalysts containing an imidazolium salt and a Schiff base N2 - Two iron-based molten salts comprising an imidazolium and Schiff base were evaluated as catalysts for removal of carbamazepine (CBZ) from water. The catalysts were fully characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDX), nuclear magnetic resonance spectroscopy (NMR), electrospray ionisation–mass spectrometry (ESI–MS), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and nitrogen adsorption–desorption isotherms (BET). Additionally, the formation of photo-sensitized oxygen was investigated by spin-trapping using electron spin resonance (ESR). The catalytic activity in heterogeneous oxidation of the micropollutant (CBZ) was also evaluated. The effects of catalyst loading, pH, H2O2 dosage and UV light on the oxidation of the selected compound were investigated. After 15 min of UVA irradiation in the presence of 200 μM H2O2, CBZ was completely removed over both catalysts. KW - Fe-based highly active ionic liquids KW - Characterization of catalysts KW - Removal KW - Singlet oxygen KW - Carbamazepine PY - 2016 U6 - https://doi.org/10.1016/j.apcatb.2015.10.032 SN - 0926-3373 VL - 183 SP - 335 EP - 342 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-35382 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gopala, Anil A1 - Jakubowski, Norbert A1 - Panne, Ulrich A1 - Kipphardt, Heinrich T1 - Real time monitoring of chemical transformations during catalytic reduction using gas source mass spectrometry: carbon/zinc carbonate hydroxide N2 - We report herein the utilization of a vacuum reduction distillation system (VRDS) coupled with mass spectrometry (MS) to characterize chemical transformations in thermal analysis. The system initially designed to monitor metal purification by distillation is applied for the first time to the catalytic reaction of in situ formed nickel oxide during the carbothermic reduction of zinc oxide. PY - 2010 U6 - https://doi.org/10.1039/c004179c SN - 0267-9477 SN - 1364-5544 VL - 25 SP - 1378 EP - 1380 PB - Royal Society of Chemistry CY - London AN - OPUS4-21911 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schulte, Franziska A1 - Brzezinka, K.-W. A1 - Lutzenberger, K. A1 - Stege, H. A1 - Panne, Ulrich T1 - Raman spectroscopy of synthetic organic pigments used in 20th century works of art N2 - Raman microscopy allows a non-destructive characterisation of inorganic and organic painting materials such as pigments and organic dyestuffs. The objectives of this study are the more recent organic pigments typically present in paintings and other art works from the 20th century. More than 20 organic synthetic pigments from different chemical classes could be identified by Raman spectroscopy using different excitation wavelengths (457.9, 476.5, 487.9, 514.5, 632.8, and 1064 nm). To evaluate the performance for real paint samples, varying paint mixtures of the Hansa Yellow pigment PY 3 and the binding medium Mowilith, a polyvinyl acetate (PVAC) compound, were characterised; PY 3 was determined at a 1 wt% level in the binder. In addition, commercial tube paints containing the quinacridone violet PV 19 were studied. The pigment was clearly identified in all of these more complex oil and acrylic paints. Finally, alizarin (PR 83) and a green copper phthalocyanine pigment (PG 7) could unambiguously be identified by Raman microscopy in the painting Woman with mandolin in yellow and red of Max Beckmann dating 1950. The discovery of a red naphthol AS pigment by Raman spectroscopy in a sample from the Three field workers by Georg Baselitz (1964/1965) demonstrated that in some cases complementary chromatographic methods are needed for a comprehensive identification of the organic pigments. KW - Raman microscopy KW - FT-Raman spectroscopy KW - Synthetic organic pigments KW - Modern art PY - 2008 U6 - https://doi.org/10.1002/jrs.2021 SN - 0377-0486 SN - 1097-4555 VL - 39 IS - 10 SP - 1455 EP - 1463 PB - Wiley CY - Chichester AN - OPUS4-18401 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gornushkin, Igor B. A1 - Panne, Ulrich T1 - Radiative models of laser-induced plasma and pump-probe diagnostics relevant to laser-induced breakdown spectroscopy N2 - The paper describes past and present efforts in modeling of laser-induced plasma and overviews plasma diagnostics carried out by pump-probe techniques. Besides general information on existing plasma models, the emphasis is given to models relevant to spectrochemical analysis, i.e. models of radiating plasma. Special attention is paid to collisional-radiative (CR) and collisional-dominated (CD) plasma models where radiative processes play an important role. Also, calibration-free (CF) models are considered which may endow with the possibility for standardless spectroscopic analysis. In the diagnostic part, only methods based on the use of additional diagnostic tools (auxiliary lasers, optics, and probes) are described omitting those based on plasma own radiation. A short review is provided on image-based diagnostics (shadowgraphy, schlieren, and interferometry), absorption and fluorescence, Langmuir probe, and less frequently used cavity ringdown and Thomson scattering methods. KW - Laser ablation KW - Modeling KW - Plasma diagnostics KW - Laser-induced breakdown spectroscopy PY - 2010 U6 - https://doi.org/10.1016/j.sab.2010.03.021 SN - 0584-8547 SN - 0038-6987 VL - 65 IS - 5 SP - 345 EP - 359 PB - Elsevier CY - Amsterdam AN - OPUS4-24003 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meyer, Klas A1 - Rademann, K. A1 - Panne, Ulrich A1 - Maiwald, Michael T1 - Quantitative NMR spectroscopy for gas analysis for production of primary reference gas mixtures N2 - Due to its direct correlation to the number of spins within a sample quantitative NMR spectroscopy (qNMR) is a promising method with absolute comparison abilities in complex systems in technical, as well as metrological applications. Most of the samples studied with qNMR are in liquid state in diluted solutions, while gas-phase applications represent a rarely applied case. Commercially available NMR equipment was used for purity assessment of liquid and liquefied hydrocarbons serving as raw materials for production of primary reference gas standards. Additionally, gas-phase studies were performed within an online NMR flow probe, as well as in a high-pressure NMR setup to check feasibility as verification method for the composition of gas mixtures. KW - Quantitative NMR spectroscopy KW - Gas-phase NMR spectroscopy KW - Primary reference gas mixtures PY - 2017 UR - http://www.sciencedirect.com/science/article/pii/S1090780716302518 U6 - https://doi.org/10.1016/j.jmr.2016.11.016 SN - 1090-7807 SN - 1096-0856 VL - 275 SP - 1 EP - 10 AN - OPUS4-38803 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Drescher, Daniela A1 - Giesen, Charlotte A1 - Traub, Heike A1 - Panne, Ulrich A1 - Kneipp, Janina A1 - Jakubowski, Norbert T1 - Quantitative imaging of gold and silver nanoparticles in single eukaryotic cells by laser ablation ICP-MS N2 - Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was utilized for spatially resolved bioimaging of the distribution of silver and gold nanoparticles in individual fibroblast cells upon different incubation experiments. High spatial resolution was achieved by optimization of scan speed, ablation frequency, and laser energy. Nanoparticles are visualized with respect to cellular substructures and are found to accumulate in the perinuclear region with increasing incubation time. On the basis of matrix-matched calibration, we developed a method for quantification of the number of metal nanoparticles at the single-cell level. The results provide insight into nanoparticle/cell interactions and have implications for the development of analytical methods in tissue diagnostics and therapeutics. KW - Imaging KW - Cell KW - Nanoparticles KW - Laser ablation KW - ICP-MS PY - 2012 U6 - https://doi.org/10.1021/ac302639c SN - 0003-2700 SN - 1520-6882 VL - 84 IS - 22 SP - 9684 EP - 9688 PB - American Chemical Society CY - Washington, DC AN - OPUS4-27440 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Larissa A1 - Herrmann, Antje Jutta A1 - Techritz, Sandra A1 - Panne, Ulrich A1 - Jakubowski, Norbert T1 - Quantitative characterization of single cells by use of immunocytochemistry combined with multiplex LA-ICP-MS N2 - Actual research demonstrates that LA-ICP-MS is capable of being used as an imaging tool with cellular resolution. The aim of this investigation was the method development for LA-ICP-MS to extend the versatility to quantitative and multiplexing imaging of single eukaryotic cells. For visualization of individual cells selected, lanthanide-labeled antibodies were optimized for immuno-imaging of single cells with LA-ICP-MS. The molar content of the artificial introduced labels per cell was quantified using self-made nitrocellulose-coated slides for matrix-matched calibration and calculated amounts were in the range of 3.1 to 17.8 atmol per cell. Furthermore, the quantification strategy allows a conversion of 2D intensity profiles based on counts per second (cps) to quantitative 2D profiles representing the molar amount of the artificial introduced elemental probes per pixel for each individual cell. KW - Single cell analysis KW - Bioimaging by LA-ICP-MS KW - Immunoassays PY - 2017 U6 - https://doi.org/10.1007/s00216-017-0310-1 SN - 1618-2642 SN - 1618-2650 VL - 409 IS - 14 SP - 3667 EP - 3676 PB - Springer AN - OPUS4-40068 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - García Fernández, J. A1 - Sánchez-González, C. A1 - Bettmer, J. A1 - Llopi, J. A1 - Jakubowski, Norbert A1 - Panne, Ulrich A1 - Montes-Bayón, M. T1 - Quantitative assessment of the metabolic products of iron oxide nanoparticles to be used as iron supplements in cell cultures N2 - Iron nanoparticles (NPs) metabolism is directly associated to human health due to their use as anemia treatment and should be studied in detail in cells. Here we present a speciation strategy for the determination of the metabolic products of iron oxide nanoparticles coated by tartaric and adipic acids in enterocytes-like cell models (Caco-2 and HT-29). Such methodology is based on the use of SDS-modified reversed phase high performance liquid chromatography (HPLC) separation using inductively coupled plasma-mass spectrometry (ICP-MS) as Fe selective detector. Post-column isotope dilution analysis is used as quantification tool by adding Fe-57 as isotopically enriched standard. To assess the separation capability of the method, two different iron nanostructures: iron sucrose nanoparticles -Venofer®- used as model suspension and iron tartrate/adipate-modified nanoparticles, both of about 4 nm (core size) were evaluated. The two nanostructures were injected into the system showing good peak profiles and quantitative elution recoveries (>80%) in both cases. In addition, both nanoparticulate fractions could be based-line separated from ionic iron species, which needed to be complexed with 1mM citrate to elute from the column. Exposed cells up to 0.5mM of iron tartrate/adipate-modified nanoparticles were specifically treated to extract the internalized NPs and the extracts examined using the proposed strategy. The obtained results revealed the presence of three different fractions corresponding to nanoparticle aggregates, dispersed nanoparticles and soluble iron respectively in a single chromatographic run. Quantitative experiments (column recoveries ranging from 60 to 80%) revealed the presence of the majority of the Fe in the nanoparticulated form (>75%) by summing up the dispersed and aggregate particles. Such experiments point out the high uptake and low solubilization rate of the tartrate/adipate NPs making these structures highly suitable as Fe supplements in oral anemia treatments. KW - Fe nanoparticles metabolism KW - Cells KW - HPLC-ICP-MS KW - Species-unspecific on-line isotope dilution PY - 2018 U6 - https://doi.org/10.1016/j.aca.2018.08.003 SN - 0003-2670 VL - 1039 SP - 24 EP - 30 PB - Elsevier CY - Amsterdam AN - OPUS4-46817 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Phukphatthanachai, P. A1 - Panne, Ulrich A1 - Traub, Heike A1 - Pfeifer, Jens A1 - Vogl, Jochen T1 - Quantification of sulphur in copper and copper alloys by GDMS and LA-ICP-MS, demonstrating metrological traceability to the international system of units N2 - The quantification of the sulphur mass fraction in pure copper and copper alloys by GDMS and LA-ICP-MS revealed a lack of traceability mainly due to a lack of suitable certified reference materials for calibrating the instruments. Within this study GDMS and LA-ICP-MS were applied as routine analytical tools to quantify sulphur in copper samples by applying reference materials as calibrators, which were characterized for their sulphur mass fraction by IDMS beforehand. Different external calibration strategies were applied including a matrix cross type calibration. Both techniques with all calibration strategies were validated by using certified reference materials (others than those used for calibration) and good agreement with the reference values was achieved except for the matrix cross type calibration, for which the agreement was slightly worse. All measurement results were accompanied by an uncertainty statement. For GDMS, the relative expanded (k = 2) measurement uncertainty ranged from 3% to 7%, while for LA-ICP-MS it ranged from 11% to 33% when applying matrix-matched calibration in the sulphur mass fraction range between 25 mg kg-1 and 1300 mg kg-1. For cross-type calibration the relative expanded (k = 2) measurement uncertainty need to be increased to at least 12% for GDMS and to at least 54% for LA-ICP-MS to yield metrological compatibility with the reference values. The so obtained measurement results are traceable to the international system of units (SI) via IDMS reference values, which is clearly illustrated by the unbroken chain of calibrations in the metrological traceability scheme. KW - Sulfur KW - Copper KW - GDMS KW - LA-ICP-MS KW - Uncertainty KW - Traceability KW - SI PY - 2021 U6 - https://doi.org/10.1039/d1ja00137j SN - 0267-9477 VL - 36 IS - 11 SP - 2404 EP - 2414 PB - Royal Society of Chemistry AN - OPUS4-53412 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Löhr, Konrad A1 - Traub, Heike A1 - Wanka, Antje Jutta A1 - Panne, Ulrich A1 - Jakubowski, Norbert T1 - Quantification of metals in single cells by LA-ICP-MS: Comparison of single spot analysis and imaging N2 - LA-ICP-MS is increasingly used for single cell analysis in two different detection modes using either the imaging mode with subcellular resolution or alternatively single spot analysis of cells with a larger laser spot size. This study compares the analytical figures of merit of both detection modes (signal to noise, precision, accuracy, throughput), as well as ease of operation and data evaluation. Adherent 3T3 fibroblast cells were stained with two metal dyes (mDOTA-Ho, Ir-DNA-intercalator) and several dozen cells were measured using both modes. We found a ten times higher throughput for single spot analysis, which has as well a straightforward data analysis, shortening the total analysis time further. The signal to noise ratio for single spot analysis was found to be slightly better compared to the signal to noise of pixels in imaging. The mean metal intensity per single cell differed by only 10% between both modes and obtained distributions were found to show no statistically significant differences. Using matrix matched calibration based on standards spotted onto nitrocellulose membrane, we achieved detection limits (10s) of 12 fg for Ir and 30 fg for Ho and quantified 57 +/-35 fg Ir and 1192 +/- 707 fg Ho per single cell. Compared to a conventional ICP-MS measurement of a digest of about 60000 cells, 54% of Ir content and 358% Ho content was found using quantitative LA-ICP-MS. The difference might be a consequence of the two metal dyes binding to different structures of the cell and therefore might behave differently in sample preparation for conventional and LA-ICP-MS. KW - Cells KW - Laser ablation KW - ICP-MS KW - Metals KW - Quantification PY - 2018 U6 - https://doi.org/10.1039/c8ja00191j SN - 0267-9477 VL - 33 IS - 9 SP - 1579 EP - 1587 PB - RSC Royal Society of Chemistry CY - London AN - OPUS4-46441 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Loehr, Konrad A1 - Jakubowski, Norbert A1 - Wanka, Antje Jutta A1 - Traub, Heike A1 - Panne, Ulrich T1 - Quantification of metals in single cells by LA-ICP-MS comparison of single spot analysis and imaging N2 - LA-ICP-MS is increasingly used for single cell analysis in two different detection modes using either the imaging mode with subcellular resolution or alternatively single spot analysis of cells with a larger laser spot size. This study compares the analytical figures of merit of both detection modes (signal to noise, precision, accuracy, throughput), as well as ease of operation and data evaluation. Adherent 3T3 fibroblast cells were stained with two metal dyes (mDOTA-Ho, Ir-DNA-intercalator) and several dozen cells were measured using both modes. We found a ten times higher throughput for single spot analysis, which has as well a straightforward data analysis, shortening the total analysis time further. The signal to noise ratio for single spot analysis was found to be slightly better compared to the signal to noise of pixels in imaging. The mean metal intensity per single cell differed by only 10% between both modes and obtained distributions were found to show no statistically significant differences. Using matrix matched calibration based on standards spotted onto nitrocellulose membrane, we achieved detection limits (10 σ) of 12 fg for Ir and 30 fg for Ho and quantified 57 ± 35 fg Ir and 1,192 ± 707 fg Ho per single cell. Compared to a conventional ICP-MS measurement of a digest of ~60,000 cells, 54 % of Ir content and 358 % Ho content was found using quantitative LA-ICP-MS. The difference might be a consequence of the two metal dyes binding to different structures of the cell and therefore might behave differently in sample preparation for conventional and LA-ICP-MS. KW - Single cell analysis KW - LA-ICP-MS PY - 2018 U6 - https://doi.org/10.1039/c8ja00191j SN - 0267-9477 SN - 1364-5544 VL - 33 IS - 9 SP - 1579 EP - 1587 PB - Royal Society of Chemistry AN - OPUS4-45903 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kühn, Andreas A1 - Scharf, Oliver A1 - Ordavo, I. A1 - Riesemeier, Heinrich A1 - Reinholz, Uwe A1 - Radtke, Martin A1 - Berger, Achim A1 - Ostermann, Markus A1 - Panne, Ulrich T1 - Pushing the limits for fast spatially resolved elemental distribution patterns N2 - A new setup for fast spatially resolved measurements of elemental trace amounts under total reflection conditions using a new colour X-ray camera is described. Samples prepared on conventional total reflection X-ray fluorescence (TXRF) reflectors were measured at BESSY II synchrotron. A spatial resolution of 50 × 50 µm² was obtained, while the required time for the investigation of a 10 × 10 mm² sample is 30 seconds. The set-up is up to 350 times faster than conventional X-ray fluorescence systems for elemental traces. The major components of the X-ray camera are polycapillary optics and a pn-CCD chip with an active area of 13 × 13 mm². This area is divided into 264 × 264 pixels of 48 × 48 µm². A full X-ray spectrum with a resolution of 152 eV @ 5.9 keV and a chip temperature of 246 K is recorded for each pixel. The chip has a read-out rate of 400 Hz. PY - 2011 U6 - https://doi.org/10.1039/c1ja10069f SN - 0267-9477 SN - 1364-5544 VL - 26 SP - 1986 EP - 1989 PB - Royal Society of Chemistry CY - London AN - OPUS4-24386 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gopala, Anil A1 - Kipphardt, Heinrich A1 - Matschat, Ralf A1 - Panne, Ulrich T1 - Process methodology for the small scale production of m6N5 purity zinc using a resistance heated vacuum distillation system N2 - Ultra high purity Zn (m6N5) was obtained through triple vacuum distillation using an m4N5 Zn as input material. High-volatile impurities were removed from the zinc matrix by vacuum evaporation, while traces having lower volatility than the matrix remained in the residual material after finishing of the entire purification process. The time required for the removal of the main high-volatile impurity (Cd) was monitored using a connected gas source mass spectrometer. During distillation the Zn vapor of the distillate was condensed on the cap of a glassy carbon crucible which was water cooled by a movable copper block. The temperatures were optimized for the removal of the volatiles and for the distillation process using vapor pressure data. High resolution glow discharge mass spectrometry was applied for the analysis and purity evaluation of the distilled and input zinc. The analysis confirmed the reduction of the metallic impurities from 43 mg kg-1 to 0.5 mg kg-1 (m6N5) after three consecutive vacuum distillations. An increase in the grain size and a decrease in the micro-hardness were observed for the purified Zn material. KW - Ultra high purity KW - Vacuum distillation KW - High resolution glow discharge mass KW - Spectrometry KW - Micro-hardness KW - Zinc KW - Purification PY - 2010 U6 - https://doi.org/10.1016/j.matchemphys.2010.02.080 SN - 0254-0584 VL - 122 IS - 1 SP - 151 EP - 155 PB - Elsevier CY - Amsterdam AN - OPUS4-21127 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rudtsch, S. A1 - Gusarova, Tamara A1 - Aulich, A. A1 - Fahr, M. A1 - Fischer, J. A1 - Kipphardt, Heinrich A1 - Matschat, Ralf A1 - Panne, Ulrich T1 - Procedure for the impurity-related correction at the indium fixed-point N2 - Determining the influence of impurities on the fixed-point emperatures of the ITS-90 requires the completion of several tasks. In this paper, the Progress made at Physikalisch-Technische Bundesanstalt (PTB) and BAMFederal Institute for Materials Research and Testing is presented and remaining questions are discussed. The projected characterization procedure at PTB, which is based on the established SIE method (sum of the individual estimates), using a new indium fixed-point cell is described as an example. This procedure includes an SI-traceable chemical Analysis of the material in the fixed-point cell with sufficiently low uncertainties, the individual experimental determination of the influence of the quantified impurities on the fixed-point temperature, and the establishment of direct links to the phase-transition temperatures of the national standard and of an assumed material of ideal purity. A characteristic difference to the common practice is the chemical analysis of the fixed-point metal being done after determining the cell’s freezing temperature. This allows for the detection and consideration of contamination and purification effects due to the filling process, or due to the contact with the carbon crucible and other parts of the fixed-point cell. A chemical analysis of an indium fixed-point was carried out by BAM with relative measurement uncertainties below 30 % which have not been previously achieved. The results provide evidence for the precipitation of some impurities, which is apparently inconsistent with the corresponding binary phase diagrams, but was explained in a recent publication. Implications for the use of the SIE method shall be described briefly at the end. KW - Chemical analysis KW - Fixed-points KW - Impurities KW - ITS-90 PY - 2011 U6 - https://doi.org/10.1007/s10765-011-0915-0 SN - 0195-928X SN - 1572-9567 VL - 32 IS - 1-2 SP - 293 EP - 302 PB - Springer CY - Dordrecht AN - OPUS4-23373 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -