TY - JOUR A1 - Michalik-Onichimowska, Aleksandra A1 - Beitz, T. A1 - Panne, Ulrich A1 - Löhmannsröben, H.-G. A1 - Riedel, Jens T1 - Laser ionization ion mobility spectrometric interrogation of acoustically levitated droplets JF - Analytical and Bioanalytical Chemistry N2 - Acoustically levitated droplets have been suggested as compartmentalized, yet wall-less microreactors for high-throughput reaction optimization purposes. The absence of walls is envisioned to simplify up-scaling of the optimized reaction conditions found in the microliter volumes. A consequent pursuance of high-throughput chemistry calls for a fast, robust and sensitive analysis suited for online interrogation. For reaction optimization, targeted Analysis with relatively low sensitivity suffices, while a fast, robust and automated sampling is paramount. To follow this approach, in this contribution, a direct coupling of levitated droplets to a homebuilt ion mobility spectrometer (IMS) is presented. The sampling, Transfer to the gas phase, as well as the ionization are all performed by a single exposure of the sampling volume to the resonant output of a mid-IR laser. Once formed, the nascent spatially and temporally evolving analyte ion cloud needs to be guided out of the acoustically confined trap into the inlet of the ion mobility spectrometer. Since the IMS is operated at ambient pressure, no fluid dynamic along a pressure Gradient can be employed. Instead, the transfer is achieved by the electrostatic potential gradient inside a dual ring electrode ion optics, guiding the analyte ion cloud into the first stage of the IMS linear drift tube accelerator. The design of the appropriate atmospheric pressure ion optics is based on the original vacuum ion optics design of Wiley and McLaren. The obtained experimental results nicely coincide with ion trajectory calculations based on a collisional model. KW - Ambient pressure laser ionization KW - Ionmobility spectrometry KW - Acoustic levitation KW - ion optics PY - 2019 DO - https://doi.org/10.1007/s00216-019-02167-5 VL - 411 IS - 30 SP - 8053 EP - 8061 PB - Springer CY - Heidelberg AN - OPUS4-50132 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 JF - Chemistry A European Journal 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 DO - 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 - 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 JF - Materials 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 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506609 DO - https://doi.org/10.3390/ma13061447 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 - Rosenkranz, Daniel A1 - Kriegel, F. L. A1 - Mavrakis, E. A1 - Pergantis, S. A. A1 - Reichardt, Ph. A1 - Tentschert, J. A1 - Jakubowski, Norbert A1 - Laux, P. A1 - Panne, Ulrich T1 - Improved validation for single particle ICP-MS analysis using a pneumatic nebulizer / microdroplet generator sample introduction system for multi-mode nanoparticle determination JF - Analytica Chimica Acta N2 - This study reports on the development of a single-particle (sp) inductively coupled plasma mass spectrometry (ICP-MS) technique suitable for the multi-mode determination of nanoparticle (NP) metal mass fraction and number concentration. The described technique, which is based on a dual inlet System consisting of a pneumatic nebulizer (PN) and a microdroplet generator (MDG), allows for the sequential introduction of ionic metal calibrant solutions and nanoparticle suspensions via all combinations of the two inlets; thus allowing for a combination of three independent modes of analysis. A novel interface, assembled using standard analytical components (a demountable quartz ICP-MS torch, flexible nonconducting silicon tubing and various connectors), was used to interface the dual inlet system to an ICP-MS. The interface provided improved functionality, compared to a previous design. It is now possible to conveniently exchange and introduce standard solutions and samples via all inlet combinations, analyze them, and also wash the sample inlet systems while the whole setup is still connected to an operating ICP-MS. This setup provided seamless and robust operation in a total of three analysis modes, i.e. three ways to independently determine the metal mass fraction and NP number concentration. All three analyses modes could be carried out within a single analytical run lasting approximately 20 min. The unique feature of the described approach is that each analysis mode is based on a different. KW - Nanomaterials KW - Nanoparticles KW - Single particle ICP-MS KW - Microdroplet generator PY - 2020 DO - https://doi.org/10.1016/j.aca.2019.11.043 VL - 1099 SP - 16 EP - 25 PB - Elsevier B.V. AN - OPUS4-50361 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 JF - Journal of Analytical Atomic Spectrometry 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 DO - 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 - 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 JF - Journal of Analytical Atomic Spectrometry 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 DO - 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 - 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 JF - Spectrochimica Acta Part B 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 DO - 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 - 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 JF - Journal of Analytical Atomic Spectrometry 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 DO - 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 - Hoffmann, Holger A1 - Knizia, Christian A1 - Kuhne, Maren A1 - Panne, Ulrich A1 - Schneider, Rudolf T1 - LC–ELISA as a contribution to the assessment of matrix effects with environmental water samples in an immunoassay for estrone (E1) JF - Accreditation and Quality Assurance N2 - Estrone (E1), a metabolite of the estrogenic hormones 17β-estradiol (β-E2) and 17α-estradiol (α-E2), is itself a potent estrogen which can have a significant impact on the hormonal balance. Due to ist high potential for adverse effects on human health and aquatic life even at pg/L to ng/L levels, its appearance in water should be monitored. E1 has also been considered a marker substance for the presence of other estrogens. This study presents a newly developed direct competitive enzymelinked immunosorbent assay (ELISA) for quantification of E1 in environmental water samples using new monoclonal antibodies. The quantification range of the ELISA is 0.15 μg/L to 8.7 μg/L E1, and the limit of detection is around 60 ng/L for not pre-concentrated water samples. A pre-concentration step after careful selection of suitable phases for SPE was developed, too. The influence of organic solvents and natural organic matter on the ELISA was assessed. The high selectivity of the monoclonal antibody was demonstrated by determining the cross-reactivity against 20 structurally related compounds. For the assessment of matrix effects, a concept (“LC–ELISA”) is thoroughly exploited, i.e., separating complex samples by HPLC into 0.3 min fractions and determination of the apparent E1 concentration. Furthermore, fractions with interferences for nontarget/suspected-target analysis can be assigned. A dilution approach was applied to distinguish between specific interferences (cross-reactants) and non-specific interferences (matrix effects). In the determination of 18 environmental samples, a good agreement of the E1 concentration in the respective fractions was obtained with mean recoveries of 103 % to 132 % comparing ELISA to LC–MS/MS. KW - Validierung KW - Immunoassay KW - Matrixeffekte KW - Abwasser KW - Oberflächenwasser KW - ELISA KW - LC-MS/MS KW - Hormone KW - Endokrine Disruptoren PY - 2018 DO - https://doi.org/10.1007/s00769-018-1351-7 SN - 1432-0517 SN - 0949-1775 VL - 23 IS - 6 SP - 349 EP - 364 PB - Springer CY - Heidelberg AN - OPUS4-46891 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Recknagel, Sebastian A1 - Koch, Matthias A1 - Wise, S. A. A1 - Panne, Ulrich T1 - Fifteenth international symposium on biological and environmental reference materials (BERM-15) JF - Accreditation and Quality Assurance N2 - The 15th International Symposium on Biological and Environmental Reference Materials (BERM-15), organized by BAM, took place at in Berlin in September 2018. An overview on main topics of the conference is given. KW - BERM KW - Reference materials PY - 2019 DO - https://doi.org/10.1007/s00769-019-01377-9 SN - 1432-0517 SN - 0949-1775 VL - 24 IS - 3 SP - 249 EP - 250 PB - Springer Verlag AN - OPUS4-48203 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -