TY - JOUR A1 - Schwaar, Timm A1 - Lettow, Maike A1 - Remmler, Dario A1 - Börner, H. G. A1 - Weller, Michael G. T1 - Efficient Screening of Combinatorial Peptide Libraries by Spatially Ordered Beads Immobilized on Conventional Glass Slides N2 - Screening of one-bead-one-compound (OBOC) libraries is a proven procedure for the identification of protein-binding ligands. The demand for binders with high affinity and specificity towards various targets has surged in the biomedical and pharmaceutical field in recent years. The traditional peptide screening involves tedious steps such as affinity selection, bead picking, sequencing, and characterization. Herein, we present a high-throughput “all-on-one chip” system to avoid slow and technically complex bead picking steps. On a traditional glass slide provided with an electrically conductive tape, beads of a combinatorial peptide library are aligned and immobilized by application of a precision sieve. Subsequently, the chip is incubated with a fluorophore-labeled target protein. In a fluorescence scan followed by matrix-assisted laser desorption/ionization (MALDI)-time of flight (TOF) mass spectrometry, high-affinity binders are directly and unambiguously sequenced with high accuracy without picking of the positive beads. The use of an optimized ladder sequencing approach improved the accuracy of the de-novo sequencing step to nearly 100%. The new technique was validated by employing a FLAG-based model system, identifying new peptide binders for the monoclonal M2 anti-FLAG antibody, and was finally utilized to search for IgG-binding peptides. In the present format, more than 30,000 beads can be screened on one slide. KW - Peptide library KW - HTS KW - Target KW - MALDI KW - Mass spectrometry KW - Biochip KW - Lab-on-a-Chip KW - Array KW - Screening KW - Ladder sequencing KW - Binder KW - Pharmaceutical PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-478973 UR - https://www.mdpi.com/2571-5135/8/2/11 DO - https://doi.org/10.3390/ht8020011 VL - 8 IS - 2 SP - 1 EP - 15 PB - MDPI CY - Basel AN - OPUS4-47897 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Panne, Ulrich T1 - Analytical Sciences: From Ostwald's maid to enabling science N2 - The talk will address the paradigm shift in Analytical Sciences in regard to chemistry as a discipline. To illustrate this metamorphose examples from spectroschemical analysis, ufluidics, bioanalysis, and the didgital transformation of analytical sciences are discussed. T2 - GDCh-Wissenschaftsforum 2019 CY - Aachen, Germany DA - 15.09.2019 KW - Spectrochemical analysis KW - Analytical Sciences PY - 2019 AN - OPUS4-51471 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Abad Andrade, Carlos Enrique A1 - Florek, S. A1 - Becker-Ross, H. A1 - Huang, M.-D. A1 - Muench, S. A1 - Okruss, M. A1 - Mao, X. A1 - Gonzalez, J. A1 - Zorba, V. A1 - Recknagel, Sebastian A1 - Tatzel, Michael A1 - Vogl, Jochen A1 - Jakubowski, Norbert A1 - Panne, Ulrich T1 - Critical evaluation of optical spectrometry vs mass spectrometry for stable isotope analysis N2 - Mass spectrometric Methods MC-ICP-MS and TIMS) are without doubt the working horse of stable isotope analysis. However, drawbacks of these methods include the high costs for instruments and their operation, experienced operators and elaborate chromatographic sample preparation which are time consuming. Optical spectrometric methods are proposed as faster and low-cost alternative for the analysis of isotope ratios of selected elements by means of high-resolution continuum source molecular absorption spectrometry (HR-CS-MAS) and laser ablation molecular isotopic spectrometry (LAMIS). First, stable isotope amount compositions of boron (B) and magnesium (Mg) were determined based on the absorption spectra of in-situ generated heteronuclear diatomic molecules (MH or MX) in graphite furnace HR-CS-MAS. The use of a modular simultaneous echelle spectrograph (MOSES) helps to find the maximal isotope shift in the diatomic molecular spectra produced in a graphite furnace by using isotopic spike solutions. Isotopes of boron (10B and 11B) were studied via their hydrides for the electronic transition X 1Σ+ → A 1Π. The spectrum of a given sample is a linear combination of the 10BH molecule and its isotopologue 11BH. Therefore, the isotopic composition of samples can be calculated by a partial least square regression (PLS). For this, a spectral library was built by using samples and spikes with known isotope composition. Boron isotope ratios measured by HR-CS-MAS are identical with those measured by mass spectrometric methods at the 0.15 ‰ level. Similar results were obtained for a multiple isotope system like Mg (24Mg, 25Mg, and 26Mg), where isotope shifts of their isotopologues can be resolved in the MgF molecule for the electronic transition X 2Σ → A 2 Πi. Finally, the application of molecular spectrometry via emission by LAMIS is compared and discussed. T2 - European Winter Conference on Plasma Spectrochemistry EWCPS 2019 CY - Pau, France DA - 03.02.2019 KW - Isotope analysis KW - HR-CS-MAS KW - LIBS KW - MS-ICP-MS KW - Optical spectroscopy KW - Mass spectrometry PY - 2019 AN - OPUS4-49874 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Abad Andrade, Carlos Enrique A1 - Florek, S. A1 - Becker-Ross, H. A1 - Huang, M.-D. A1 - Muench, S. A1 - Okruss, M. A1 - Mao, X. A1 - Zorba, V. A1 - Recknagel, Sebastian A1 - Tatzel, Michael A1 - Vogl, Jochen A1 - Jakubowski, Norbert A1 - Panne, Ulrich T1 - A comparative analysis of optical spectrometry methods and MC-ICP-MS for stable isotope analysis of magnesium in geological samples N2 - Society for Applied Spectroscopy (SAS) Atomic Section Student Award. Magnesium is a major element in the hydrosphere and biosphere and plays important roles in (bio-) geochemical and physiological cycles. Mg has three stable isotopes, 24Mg, 25Mg and 26Mg. It is due to their relatively large mass difference (~8% between) that isotope fractionation leads to slight variations of isotope amount ratios in biological, environmental and geological samples. Traditionally, isotope ratios are measured by mass spectrometric methods. Their drawbacks include the high costs for instruments and their operation, experienced operators and elaborate time-consuming chromatographic sample preparation. Recently, optical spectrometric methods have been proposed as faster and low-cost alternative for the analysis of isotope ratios of selected elements by means of high-resolution continuum source molecular absorption spectrometry (HR-CS-MAS), and laser ablation molecular isotopic spectrometry (LAMIS). For the determination of Mg isotope ratios in selected rock reference materials, the molecular spectrum of the in-situ generated MgF and MgO molecules were studied and their results compared with MC-ICP-MS. By HR-CS-MAS, samples were dissolved by acid digestion and Mg isotopes analyzed with and without matrix. The absorption spectrum was recorded for MgF for the electronic transitions X 2Σ → A 2 Πi, and X 2Σ → B 2Σ+. In the case of LAMIS, we investigated the MgF molecule for the electronic transition A 2Πi → X 2Σ, as well as direct analysis by the MgO molecule for the electronic transition A 1Π+ → X 1Σ. The MgF and MgO spectra are described as the linear combination of their isotopic components or isotopologues: 24MgF, 25MgF, and 26MgF for the MgF and 24MgO, 25MgO, and 26MgO for the MgO. The isotope analysis was done by deconvolution of the MgF spectrum by partial least square regression (PLS) calibrated with enriched isotope spikes. Results were accurate with precisions ranging between 0.2 ‰ and 0.8 ‰ (2 SD, n= 10) for HR-CS-GFMAS. No statistically significant differences were observed for samples w/o matrix extraction. On the other hand, LAMIS allows the direct analysis of solid samples with the extended possibility of direct analysis, however the precision is lower due the lack of solid isotopic calibration standards. T2 - SciX 2019. 46th Annual North American Meeting of the Federation of Analytical Chemistry and Spectroscopy Societies (FACSS) CY - Palm Springs, CA, USA DA - 13.10.2019 KW - Isotope analysis KW - Diatomic molecule KW - Magnesium KW - MC-ICP-MS KW - HR-CS-MAS KW - LIBS PY - 2019 AN - OPUS4-49883 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - You, Zengchao A1 - Jakubowski, Norbert A1 - Panne, Ulrich A1 - Weidner, Steffen T1 - Separation of polystyrene nanoparticles with different coatings using 2D off-line coupling of asymmetrical flow field flow fractionation (AF4) and capillary electrophoresis (CE) 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. Two mixtures of polystyrene nanoparticles (PS-NPs) with comparable core sizes (20 nm and 50 nm) 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 and can obviouly improve separation resolution. T2 - Anakon 2019 CY - Münster, Germany DA - 25.03.2019 KW - Capillary electrophoresis (CE) KW - Nanoparticles with same nominal diameter; surface coating; two-dimensional off-line coupling KW - Asymmetrical flow field flow fractionation (AF4) PY - 2019 AN - OPUS4-47746 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) 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 - TY - CONF A1 - Abad Andrade, Carlos Enrique A1 - Florek, S. A1 - Becker-Ross, H. A1 - Mao-Dong, H. A1 - Recknagel, Sebastian A1 - Vogl, Jochen A1 - Jakubowski, Norbert A1 - Panne, Ulrich T1 - Determination of isotope ratios by molecular absorption spectrometry N2 - Boron and Magnesium present two and three stable isotopes respectevely. It is due to their relatively large mass difference (~ 10%) that isotope fractionation leads to considerable isotope amount ratio variations in the nature. These have been used as a proof of provenance of mineral and biological samples, to estimate a contamination source and to the determination of geological processes by erosion or subduction. Additionally, boron is employed in the nuclear industry due to the capability of its isotope 10B to thermal-neutron capture and therefore 10B enriched boric acid solutions are used in the cooling system of thermonuclear facilities and in the alloying of steel and carbides for protective shielding. Traditionally, isotope ratio variations have been determined by mass spectroscopic methods. Here an alternative faster and low cost method for isotope ratio determination is proposed: high-resolution continuum source molecular absorption spectrometry (HR-CS-MAS). Isotope amount ratios have been determined by monitoring the absorption spectrum of boron monohydride (BH) for boron and Magnesium monofluoride (MgF) for magnesium in a graphite furnace HR-CS-MAS. Bands (0→0) and (1→1) were evaluated. Partial least square regression (PLS) for analysis of samples and reference materials were applied. For this, a spectral library with different isotopes ratios for PLS regression was built. Results obtained are metrologically compatible with those reported by mass spectrometric methods. Moreover, a precision and accuracy of the method of ± 0.5 ‰. This accuracy and precision is comparable with those obtained by thermal ionization mass spectrometry (TIMS) and multiple collector inductively coupled plasma mass spectrometry (MC-ICP-MS) for boron isotope ratio measurements T2 - Analytik Jena Days CY - Idstein, Germany DA - 26.06.2019 KW - Isotope anaylsis KW - HR-CS-MAS KW - Boron KW - Magnesium KW - Optical spectroscopy KW - Diatomic molecule PY - 2019 AN - OPUS4-49877 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Abad Andrade, Carlos Enrique T1 - Advances and Applications of Molecular Absorption Spectrometry: from Non-Metals to Isotope Analysis N2 - The present work covers two main aspects of high-resolution continuum source graphite furnace molecular absorption spectrometry (HR-CS-GFMAS), an analytical technique for elemental trace analysis. First, a comprehensive mechanistic study of molecule formation in graphite furnaces is presented, which is a key step into the recovery of analytical signals. For this, the molecule formation of CaF was studied, which is used for the indirect analytical determination of fluorine in HR-CS-GFMAS. A zirconium coating catalyzes the CaF formation, and its structure was investigated. 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 (SEM-EDX), X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XANES and EXAFS), and Raman microspectroscopy. Here a mechanism is proposed, where ZrO2 works 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. Second, analytical methods were developed by using HR-CS-MAS as detector for non-metals and isotope analysis. Therefore, the determination of organic absorbable chlorine in water, the quantification of fluorine in consume care products with declared perfluorinated ingredients, and the determination of sulfur content in crude oils were investigated. Finally, the high resolution of the instrumentation allows to measure isotopic shifts with high precision in some observed molecular spectra. Consequently, the molecular spectra of enriched isotopes of boron and magnesium were investigated, establishing so the potential of HR-CS-MAS for the accurate and precise determination of isotopic amount ratios. Zusammenfassung Die vorliegende Arbeit befasst sich mit zwei zentralen Aspekten der High-Resolution-Continuum-Source-Molekülabsorptionsspektrometrie mit Graphitrohrtechnik (HR-CS-GFMAS), einer Analysetechnik für elementare Spurenanalyse. Der erste Teil der Arbeit umfasst eine mechanistische Studie zur Molekülbildung auf Graphitoberflächen. Dies ist ein wichtiger Schritt, um analytische Signale zu entdecken. Dazu wurde die Molekülbildung von CaF analysiert, welches für die indirekte, analytische Bestimmung von Fluor in HR-CS-GFMAS genutzt wird. Die CaF Bildung wurde mittels einer Beschichtung aus Zirconium katalysiert und deren Struktur analysiert. Die Kinetik dieser Reaktion wurde durch Beobachtung des jeweiligen Molekülspektrums bei verschiedenen Atomisierungstemperaturen beobachtet. Ein Arrheniusplot zeigte für Fluor (n = 1) eine Reaktion Pseudo-erster Ordnung. Ein Übergangszustand wurde über die mit Zirconium überzogene Grafitoberfläche isoliert und seine Struktur mittels spektroskopischer Methoden Energiedispersive Rasterelektronenmikroskopie / Röntgenspektroskopie (REM-EDX), Röntgenphoto¬elektronenspektroskopie (XPS), Röntgenabsorptionsspektroskopie (XAS) und Raman Spektroskopie untersucht. Auf Grundlage dieser Ergebnisse wird ein Mechanismus vorgeschlagen, bei dem ZrO2 als heterogener Katalysator fungiert; in Folge einer Pyrolysestufe wird ein Übergangszustand des ZrO(OCaF) aktiviert, welcher bei höheren Temperaturen CaF(g) an der Zirconium-Graphitoberfläche freisetzt. Im zweiten Teil der Arbeit werden Analysemethoden entwickelt, in dem HR-CS-MAS als Detektor für Nichtmetalle und Isotopanalyse angewandt wird. Hierfür wurde organisch gebundenes Chlor im Wasser bestimmt, der Fluorgehalt in Pflegeprodukten mit perfluorierten Inhaltsstoffen quantifiziert und der Schwefelgehalt in Erdöl untersucht. Weiterhin ermöglicht die hohe Auflösung der Messgeräte eine präzise Bestimmung der Isotopenverschiebung einiger untersuchter Molekülspektren. Daher wurden die Molekülspektren angereicherter Bor- und Magnesiumisotope untersucht. Auf diese Weise wurde das Potential von HR-CS-MAS für die akkurate und präzise Bestimmung von Isotop-Mengenverhältnissen nachgewiesen. KW - Isotope analysis KW - Non-metals analysis KW - Molecular absorption spectrometry KW - Boron KW - Fluorine KW - Graphite furnace KW - HR-CS-MAS KW - Applied optical spectroscopy PY - 2019 UR - https://hu-berlin.hosted.exlibrisgroup.com/permalink/f/jl2ii5/HUB_UB_ALMA_DS21669801300002882 SP - X EP - 118 CY - Berlin, Germany AN - OPUS4-49891 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neamtu, Mariana A1 - Nadejde, C. A1 - Hodoroaba, Vasile-Dan A1 - Schneider, Rudolf A1 - Ababei, G. A1 - Panne, Ulrich T1 - Photocatalysis of γ-cyclodextrin-functionalised Fe3O4 nanoparticles for degrading Bisphenol A in polluted waters N2 - The efficiency, relatively low cost and eco-friendly nature of hydrogen peroxide-assisted photocatalysis treatment procedures are significant advantages over conventional techniques for wastewater remediation. Herein, we evaluate the behaviour of g-cyclodextrin (g-CD) immobilised on either bare or chitosan (CS)–functionalised Fe3O4 nanoparticles, for photodegrading Bisphenol A (BPA) in ultrapure water and in real wastewater samples. The BPA removal efficiencies with Fe3O4/g-CD and Fe3O4/CS/g-CD were compared with those of Fe3O4/b-CD, and were monitored under UVA irradiation at near-neutral pH. The addition of H2O2 at low concentrations (15 mmol L-1) significantly increased BPA photodegradation in the presence of each nanocomposite. The highest catalytic activity was shown by both Fe3O4/g-CD and Fe3O4/CS/g-CD nanocomposites (,60 and 27%BPA removal in ultrapure water and real wastewater effluent, respectively). Our findings reveal the superior performance of g-CD-functionalised Fe3O4 relative to that of Fe3O4/b-CD. The use of CD-based nanocomposites as photocatalytic materials could be an attractive option in the pre- or post-treatment stage of wastewaters by advanced oxidation processes before or after biological treatment. KW - Photooxidation KW - Sonochemical synthesis KW - Wastewater PY - 2019 DO - https://doi.org/10.1071/EN18181 SN - 1448-2517 VL - 16 IS - 2 SP - 125 EP - 136 PB - CSIRO Publishing CY - Clayton South AN - OPUS4-48316 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Abad Andrade, Carlos Enrique A1 - Florek, S. A1 - Becker-Ross, H. A1 - Okruss, M. A1 - Jakubowski, Norbert A1 - Tatzel, Michael A1 - Vogl, Jochen A1 - Recknagel, Sebastian A1 - Panne, Ulrich T1 - Shedding light on global warming: high-resolution optical spectroscopy for magnesium isotope analysis N2 - Magnesium is a major element in the hydrosphere and biosphere, and it is direct correlated with the carbon cycle. Therefore, the study of its isotopic fractionation in sediments and sea water helps to understand the earth’s climate and global warming. Mg has three stable isotopes, 24Mg, 25Mg and 26Mg, and traditionally isotope amount ratios are measured by mass spectrometric methods. Their drawbacks include the high costs for instruments and their operation, experienced operators and elaborate time-consuming chromatographic sample preparation. Recently, an optical spectrometric method has been proposed as faster and low-cost alternative for the analysis of isotope ratios: high-resolution continuum source graphite furnace molecular absorption spectrometry (HR-CS-GFMAS). For the determination of Mg isotope ratios in selected rock reference materials, the high-resolution molecular absorption spectrum of in-situ generated MgF molecule was studied applying multivariate analysis and the results compared with MC-ICP-MS. Samples were dissolved by acid digestion and Mg isotopes analyzed with and without matrix extraction. The absorption spectra were recorded for MgF for the electronic transition X 2Σ → B 2Σ+. The MgF spectrum is described as the linear combination of their isotopic components or isotopologues: 24MgF, 25MgF, and 26MgF. The isotope analysis was done by deconvolution of the MgF spectrum by partial least square regression (PLS). A PLS model was built and calibrated with enriched isotope spikes and certified reference materials. Spectra data was preprocessed by a derivate of second order and venetian blinds cross-validation was employed for finding the optimum latent variables. Finally, the model was refined by a genetic algorithm which identified the best subset of variables for a precise and accurate regression. Results are compatible with those obtained by MC-ICP-MS with an accuracy of ± 0.3‰ with uncertainties ranging between 0.02 to 0.6‰. This accuracy and precision discriminate the isotope fractionation in geological samples, and it is suitable for earth’s climate studies. T2 - Adlershofer Forschungsforum 2019 CY - Berlin, Germany DA - 11.11.2019 KW - Isotope analysis KW - Geological thermometer KW - Magnesium KW - Optical spectroscopy PY - 2019 AN - OPUS4-49890 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -