TY - CONF A1 - Donsky, I. S. A1 - Lippitz, Andreas A1 - Adeli, M. A1 - Haag, R. A1 - Unger, Wolfgang T1 - 2D nanomaterials with switchable pathogen binding N2 - Graphene derivatives have shown great promise in the field of pathogen binding and sensing. Due to their diverse applications, they show a variety of activities that range from bacterial adhesion to bacterial resistance. Therefore, domination of the graphene-pathogen interactions is highly relevant for producing 2D platforms with the desired applications. In order to gain control over the interactions between graphene and biosystems, mechanisms should be fully understood. The surface functionality of graphene is one of the most important factors that dominates its interactions with biosystems and pathogens. Covalent functionalization is a robust method through which functionality, chemical structure, and subsequently physicochemical properties of graphene are abundantly manipulated. A critical issue for preparing graphene-based 2D materials with a defined surface structure, however, is controlling the functionalization in terms of number, position, and type of functional groups. T2 - 9th Joint BER II and BESSY II User Meeting CY - Berlin, Germany DA - 13.12.2017 KW - Graphene KW - Functionalization KW - XPS KW - C Kedge NEXAFS PY - 2017 AN - OPUS4-43456 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kok, H. T. A1 - Donskyi, Ievgen A1 - Adeli, M. A1 - Unger, Wolfgang A1 - Haag, R. T1 - 2D nanomaterials with switchable pathogen binding N2 - Graphene and its derivatives have recently attracted much attention for sensing and deactivating pathogens. However, mechanism of multivalent interactions at the graphene-pathogen interface are not fully understood. Since different physicochemical parameters of graphene play a role at this interface, control over graphene’s structure is necessary to study the mechanism of these interactions. In this work, zwitterionic graphene nanomaterials (ZGNMs) were synthesized with defined isoelectric points and exposure, in terms of polymer coverage and functionality. Then, the switchable interactions of ZGNMs with E. coli were investigated to study the validity of the generally proposed “trapping” mechanism for inactivating pathogens by functionalized graphene derivatives. The ZGNMs were able to controllably trap and release E. coli by crossing their isoelectric points. T2 - 4th Erlangen Symposium on Synthetic Carbon Allortopes 2017 CY - Erlangen, Germany DA - 25.09.2017 KW - Graphene KW - XPS KW - NEXAFS KW - Zwitterionic graphene nanomaterials PY - 2017 AN - OPUS4-47084 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Marzok, Ulrich A1 - Müller, Ralf A1 - Reetz, R. A1 - Lauven, G. T1 - 3D High-temperature laser profilometry during sintering N2 - Most crucial for components of complex shape or heterogeneous micro structure, precise control of sintering has decisive influence on dimensional accuracy, mechanical integrity and reliability of sintered components. In these cases, only in situ 3D high-temperature shape screening during shrinkage would allow revealing temporary sinter warpage and hereby caused potential defects. Against this background, nokra Optische Prüftechnik und Automation GmbH, HTM Reetz GmbH and BAM developed a testing device for in situ 3D shape screening for ceramic and glass-ceramic tapes up to 1000°C by means of high-temperature laser profilometry. The local repeatability of the sample-sensor distance (sample height profile) is 10 µm at 1000°C. Current work is focused on dropping these restrictions in sample shape and temperature. In a second testing device, currently being in development, samples up to 5 cm x 5 cm x 5 cm can be measured at temperatures up to 1500°C.The presentation illustrates the current state of this work and possible applications of the method. T2 - 92. DKG Jahrestagung CY - Berlin, Germany DA - 19. 03. 2017 KW - Laser profilometry KW - 3D High-temperatue shape screening KW - Sintering PY - 2017 AN - OPUS4-40449 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Hüllmann, Dino A1 - Detlefsen, Malte A1 - Kohlhoff, Harald T1 - A low-cost cable-suspended parallel manipulator for testing 3D olfaction algorithms N2 - Cable-suspended parallel manipulators have been a topic of research for multiple decades and called special attention in the fields of simulations. However, they are also well-suited for the simple evaluation of aerial-based mobile robot olfaction (MRO) algorithms, such as gas source localization and gas distribution mapping. Based on an open source framework for 3D printers, we designed a low-cost underconstrained, cable-suspended parallel manipulator. Computations are carried out purely on an Atmel ATmega2560 microcontroller. T2 - 33rd Danubia- Adria Symposium on Advances in Experimental Mechanics CY - Trieste, Italy DA - 19.09.2017 KW - Cable-suspended parallel manipulator KW - 3D KW - Mobile robot olfaction PY - 2017 AN - OPUS4-42317 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tvrdoňová, M. A1 - Ascher, Lena A1 - Jakubowski, Norbert A1 - Vaculovičová, M. A1 - Moravanská, A. A1 - Vaněčková, T. A1 - Vaculovič, T. T1 - A new strategy of reagents labeling (NPs) used in immunoassay with LA-ICP-MS N2 - Laser ablation with inductively coupled plasma is still more used in life science as biology and biomedicine and the utilization of metals and proteins determination simultaneously is also growing up. We have developed a new strategy of labeling of antibody (it can specific binds to proteins) by nanoparticles and quantum dots which is composed of thousands of atoms and thus increases the sensitivity enormously and of course decreases the Limit of detection, compare to lanthanoids labeling. The ability of successfully tagged antibodies bound to Antigen (protein) was proved by dot blot on membrane imaged by LA-ICP-MS. T2 - Euroanalysis 2017 CY - Stockholm, Sweden DA - 28.08.2017 KW - Immunoassay KW - LA-ICP-MS KW - Labeling KW - Nanoparticle PY - 2017 AN - OPUS4-43168 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reuther, R. A1 - Marvin, H. A1 - Müller, P. A1 - Löschner, K. A1 - Hodoroaba, Vasile-Dan A1 - Stintz, M. A1 - Kammer, F. v. d. A1 - Köber, R. A1 - Rauscher, H. T1 - A new tiered analytical approach and e-Tool for material classification to support the implementation of the EU Nano-Definition N2 - The EC recommendation for the definition of nanomaterial [2011/696/EU] requires the quantitative size determination of constituent particles in samples down to 1 nm. Accordingly, a material is a nanomaterial if 50 % or more of the particles are in the size range 1-100 nm. The fact that engineered nanomaterials already exist in many industrial and consumer products challenges the development of measurement methods to reliably identify, characterize and quantify their occurrence as substance and in various matrices. The EU FP7 NanoDefine project [www.nanodefine.eu] has addressed this challenge by developing a robust, readily implementable and cost-effective measurement strategy to obtain quantitative particle size distributions and to distinguish between nano and non-nano materials according to the EU definition. Based on a comprehensive evaluation of existing methodologies and intra- and inter-lab comparisons, validated measurement methods and instrument calibration procedures have been established to reliably measure the size of particles within 1-100 nm, and beyond, including different shapes, coatings and chemical compositions in industrial materials and consumer products. Case studies prove their applicability for various sectors, including food, pigments and cosmetics. Main outcome is the establishment of an integrated tiered approach including rapid screening (tier 1) and confirmatory methods (tier 2), and a user manual to guide end-users, such as manufacturers, in selecting appropriate methods. Another main product is the “NanoDefiner” e-Tool allowing the standardised / semi-automated selection of appropriate methods for material classification according to the EU definition. Results also contribute to standardization efforts, such as CEN TC 352 or ISO TC 229. T2 - EuroNanoForum 2017 CY - Valletta, Malta DA - 21.06.2017 KW - Nanomaterial classification KW - Nanoparticles KW - EC definition of nanomaterial KW - Tiered approach PY - 2017 UR - http://euronanoforum2017.eu/ AN - OPUS4-43993 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ramirez Caro, Alejandra A1 - Mota, Berta A1 - Artemeva, Elena A1 - Pauli, Jutta A1 - Schmidt, Wolfram A1 - Resch-Genger, Ute T1 - A spectroscopic study of the superplasticizer effect on early cement hydration N2 - Besides their plasticizing effect, superplasticizers (SPs) are known to retard the hydration of inorganic systems such as cement. Despite their frequent use, the understanding of these highly complex systems is still limited and the relevant parameters, which control the interaction between SPs, and cement components and reaction products are in the focus of ongoing research activities.[1] Optical methods have been successfully used for the analysis and monitoring of the interactions between a broad variety of nanoscale and molecular systems like nanoparticles of various chemical composition and different types of organic ligands or biomolecules. The potential of these methods to study processes at the interface between (hydrated) particles and the fluid phase at a very early stage of concrete formation could reveal possible mechanisms of interaction. This investigation focuses on the study of organic/inorganic mixtures consisting of cement (CEM) and cement phases (C3S and C3A) in the presence of polycarboxylate ether and organic dyes in aqueous solution (particularly alkali resistant dyes) at a water to powder ratio of 1. Diffuse reflectance as well as steady state and time resolved fluorescence spectroscopy of the above mentioned mixtures were evaluated. Based upon changes of the intensity of the reflectance and fluorescence signal and spectral changes of the dye, acting as optical reporter, a model for the interactions of dye, PCE and cement (including different cement phases) was derived which describes the very first stage of cement hydration. T2 - 2nd International Conference on Polycarboxylate Superplasticizers CY - München, Germany DA - 27.09.2017 KW - Cement KW - Superplasticizers KW - Dyes KW - Spectroscopy PY - 2017 AN - OPUS4-43365 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Carl, Peter A1 - Schneider, Rudolf A1 - Sarma, Dominik A1 - Rurack, Knut T1 - A wash-free, multiplex microbead assay for determination of emerging bioactive compounds in wastewater N2 - Pollutants of low molecular weight, such as drug residues, are in the focus of water quality assessment: some of them, like carbamazepine are only partially degraded in wastewater treatment plants. Thus, these pollutants can serve as marker substances for elimination efficiencies. Monitoring water quality demands for selective, high-throughput and multi-target analytical methods. Immunoassays, such as ELISA, offer the possibility to be highly sensitive and selective due to the specific recognition by high affinity of target molecules to antibodies (Abs). Batch-wise processing in microtiter plates allows for the necessary high-throughput, however only a single analyte can be determined within one measurement. To overcome these disadvantages, we developed a four-plex microbead-based flow cytometric assay, which is adaptable for the microtiter plate format. The modular and self-prepared bead support consists of polystyrene-core/silica-shell particles. While, the polystyrene core is used for encoding, by introducing different amounts of fluorescent dyes, the silica shell creates a solid support for the immunoassay: The target analytes, three drugs, carbamazepine, diclofenac and caffeine and the fecal marker isolithocholic acid are coupled covalently to the surface via NHS chemistry to amino groups on the surface. For determination of the pollutants, a mixture of specific Abs is incubated with the samples, to bind competitively on the “anchor” molecules on the surface of the beads or the analyte in solution. Bound antibodies are then visualized via fluorescent dye-labelled secondary Abs. Flow-cytometry allows for decoding of the beads and signal read-out, without washing the system. In order to decrease non-specific binding, we investigated different types of surface modifications, finding, that a PEG-based surface is suitable to support our immunoassay format. For maximum sensitivity, a design-of-experiment approach was chosen for optimization of the assay parameters. The resulting immunoassay is appropriate to quantify the pollutants in the low μg/L-range. T2 - EBS 2017 CY - Potsdam, Germany DA - 20.03.2017 KW - Immunoassay KW - Bead-based assay KW - Flow-cytometry PY - 2017 AN - OPUS4-39522 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Johann, Sergej A1 - Bartholmai, Matthias A1 - Neumann, Patrick P. A1 - Tiebe, Carlo A1 - Gawlitza, Kornelia A1 - Bartelmeß, Jürgen T1 - Adaptable multi-sensor device for gas detection N2 - Innovation is the catalyst for the technology of the future. It is important to develop new and better technologies that can continuously monitor the environmental impact, e.g., for air quality control or emission detection. In the recently at BAM developed Universal Pump Sensor Control (UPSC3) module, different components and sensors are fused. The combination of the individual components makes the UPSC3 module an excellent monitoring and reference system for the development and characterization of gas specific sensors. Measurements over long periods are possible, for mixed gas loads or for certain gas measurements. The system is part of a mobile sensor network of several sensor units, which can also be used as standalone systems. The motivation and objective of this research is to develop gas sensors based on fluorescence detection with range of ppm / ppb. For this task a reference system is required, which contains volatile organic compound (VOC) sensors for reference data from different scenarios. The integrated multi-sensor unit can measure different gases through the integrated 3-fold VOC sensor, which can be adapted to the addressed scenario. . The system-integrated flow control, with pump and flow sensor, allows the gas molecules to be transported directly to the VOC sensor. The entire measurement is permanently stored on an integrated memory card. If the previously determined limit range is exceeded, an alarm is generated. The system is an important tool towards further developments in the field of gas sensors and is primarily used for the validation of chemically based gas sensors. T2 - Colloquium of Optical Spectrometry (COSP) 2017 CY - Berlin, Germany DA - 27.11.2017 KW - Gas detection KW - Multi sensor device KW - Pump control KW - VOC PY - 2017 AN - OPUS4-43193 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartholmai, Matthias A1 - Johann, Sergej A1 - Wu, Cheng-Chieh A1 - Neumann, Patrick P. A1 - Hüllmann, Dino A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Kohlhoff, Harald A1 - Lilienthal, A.J. T1 - Airborne remote gas sensing and mapping N2 - Leaking methane (CH4) from infrastructures, such as pipelines and landfills, is critical for the environment but can also pose a safety risk. To enable a fast detection and localization of these kind of leaks, we developed a novel robotic platform for aerial remote gas sensing. Spectroscopic measurement methods for remote sensing of selected gases lend themselves for use on mini-copters, which offer a number of advantages for inspection and surveillance over traditional methods. No direct contact with the target gas is needed and thus the influence of the aerial platform on the measured gas plume can be kept to a minimum. This allows to overcome one of the major issues with gas-sensitive mini-copters. On the other hand, remote gas sensors, most prominently Tunable Diode Laser Absorption Spectroscopy (TDLAS) sensors have been too bulky given the payload and energy restrictions of mini-copters. Here, we present the Unmanned Aerial Vehicle for Remote Gas Sensing (UAV-REGAS), which combines a novel lightweight TDLAS sensor with a 3-axis aerial stabilization gimbal for aiming on a versatile hexacopter. The proposed system can be deployed in scenarios that cannot be addressed by currently available robots and thus constitutes a significant step forward for the field of Mobile Robot Olfaction (MRO). It enables tomographic reconstruction of gas plumes and a localization of gas sources. We also present first results showing its performance under realistic conditions. T2 - 5th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures (SMAR 2019) CY - Potsdam, Germany DA - 27.08.2019 KW - Localization of gas sources KW - Mobile Robot Olfaction KW - Tomographic reconstruction of gas plumes KW - Tunable Diode Laser Absorption Spectroscopy (TDLAS) KW - UAV-REGAS PY - 2017 AN - OPUS4-48789 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Johann, Sergej A1 - Tiebe, Carlo A1 - Gawlitza, Kornelia A1 - Bartelmeß, Jürgen A1 - Bartholmai, Matthias A1 - Hüllmann, Dino A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Kohlhoff, Harald A1 - Lilienthal, A.J. T1 - Airborne Remote Gas Sensing and Mapping N2 - Leaking methane (CH4) from infrastructures, such as pipelines and landfills, is critical for the environment but can also pose a safety risk. To enable a fast detection and localization of these kind of leaks, we developed a novel robotic platform for aerial remote gas sensing. Spectroscopic measurement methods for remote sensing of selected gases lend themselves for use on mini-copters, which offer a number of advantages for inspection and surveillance over traditional methods. No direct contact with the target gas is needed and thus the influence of the aerial platform on the measured gas plume can be kept to a minimum. This allows to overcome one of the major issues with gas-sensitive mini-copters. On the other hand, remote gas sensors, most prominently Tunable Diode Laser Absorption Spectroscopy (TDLAS) sensors have been too bulky given the payload and energy restrictions of mini-copters. Here, we present the Unmanned Aerial Vehicle for Remote Gas Sensing (UAV-REGAS), which combines a novel lightweight TDLAS sensor with a 3-axis aerial stabilization gimbal for aiming on a versatile hexacopter. The proposed system can be deployed in scenarios that cannot be addressed by currently available robots and thus constitutes a significant step forward for the field of Mobile Robot Olfaction (MRO). It enables tomographic reconstruction of gas plumes and a localization of gas sources. We also present first results showing its performance under realistic conditions. T2 - Colloquium of Optical Spectrometry (COSP) 2017 CY - Berlin, Germany DA - 27.11.2017 KW - Tunable Diode Laser Absorption Spectroscopy (TDLAS) KW - UAV-REGAS KW - Mobile Robot Olfaction KW - Tomographic reconstruction of gas plumes KW - Localization of gas sources PY - 2017 AN - OPUS4-43204 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Moufid, M. A1 - Tiebe, Carlo A1 - El Bari, N. A1 - Hübert, Thomas A1 - Bouchikhi, B. T1 - An electronic nose for the detection and discrimination of environmental pollutant gases in the aglomeration of the city of meknes N2 - The ambient air quality around residential areas is influenced by industrial objects, including industrial sewage, livestock farming and landfill sites. These sites are generating malodours or toxic gases involving degradation of ambient air quality, which may constitute a risk in human health if maximum emission limits are exceeded. Therefore, appropriate tools allowing detection of harmful or bad odorous, subsequently contributing to a reduction of odour nuisance are greatly needed. The aim of this study was to demonstrate the capability of an electronic nose E-nose to discriminate various gas samples collected from six different sites from the agglomeration of Meknès city corresponding to municipal landfill, in the city at 2 km of landfill, industrial estate wastewater, traffic road, and sheep breeding. The investigations were carried out with an E-nose system based on an array of six-commercial MQ sensors. Further, a pattern recognition technique known as Principal Component Analysis (PCA), Linear Discriminent Analysis (LDA), and Support Vector Machines (SVMs) was implemented to study the discrimination capability of the sensor array. PCA results demonstrate excellent discriminating ability of the dataset with a score of 99.47 %. Additionally, another measurement database containing 12 air atmospheric samples was projected on the previously built PCA model to check the stability of the E-nose. The LDA was applied to the same dataset and showed a good discrimination between the ambient air samples of the six sites. Furthermore, SVMs technique was also used to build a classifier and reached a score of 100 % success rate in the recognition of the analysed samples. The obtained results of six areas demonstrate the increasing interests and the applicability of E-noses for ambient air quality classification of six areas caused by emitted decomposed organic matters. T2 - Eighth International Workshop on Biosensors for Food Safety and Environmental Monitoring CY - Rabat, Morocco DA - 12.10.2017 KW - Pattern recognition methods KW - Electronic nose KW - Gas sensor KW - Malodour detection KW - Environmental analysis PY - 2017 AN - OPUS4-42525 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Rades, Steffi A1 - Wirth, Thomas A1 - Holzweber, Markus A1 - Pellegrino, F. A1 - Martra, G. T1 - Analysis of Fluorine Traces in TiO2 Nanoplatelets by SEM/EDX, AES and TOF-SIMS N2 - The synthesis of TiO2 nanoplatelets with fluorine-containing reactants is carried out using Ti (IV) butoxide as precursor and concentrated HF as shape controller, the final product requires a working up in order to eliminate or at least to reduce the amount of residual fluorides, which is realized here by well-defined thermal treatment. Qualitative investigation of the bulk elemental composition by means of EDX of TiO2 nanoparticles (NPs) has identified fluorine in case of the as-synthesized samples. EDX spectra of thermally treated products exhibit either a fluorine content close to the limit of detection. The latter holds also true for the reference sample, TiO2 NPs of bipyramidal shape and prepared by a different synthesis route. For differentiation whether fluorine is present in the bulk or at the surface of the TiO2 nanoplatelets, top-surface sensitive AES and ToF-SIMS has been applied. Secondary ions of fluorine are detected in ToF-SIMS spectra of all samples, but could be roughly quantified by measurement of same reference sample as for EDX, namely TiO2 nano-bipyramids. This revealed that the amount of fluorine within1 nm depth beneath the surface is reduced in the thermally treated specimen compared to the raw product down to a content about as low as in the reference sample. AES allows analyzing analysis of the first few nanometers from the top-surface of individual NPs by point analysis. An F KLL peak has been detected at the surface of samples of as-prepared TiO2 nanoplatelets under optimized measurement conditions, but was not detectable after their calcination, which is in agreement with ToF-SIMS results. Moreover, high resolution AES on single TiO2 nanoplatelets elucidated that the surface atomic layers surrounding the TiO2 nanopaltelet contain fluorides before thermal treatment of the NPs. T2 - 17th European Conference on Applications of Surface and Interface Analysis ECASIA 2017 CY - Montpellier, France DA - 24.09.2017 KW - Titania KW - Nanoparticles KW - Fluorine KW - SEM/EDX KW - Auger Electron Spectroscopy KW - Nanoplatelets PY - 2017 AN - OPUS4-42656 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Rades, Steffi A1 - Ortel, Erik A1 - Wirth, Thomas A1 - Holzweber, Markus A1 - Pellegrino, F. A1 - Martra, G. T1 - Analysis of fluorine traces in TiO2 nanoplatelets by SEM/EDX, AES and TOF-SIMS N2 - Hydrothermal synthesis of anatase TiO2 nanosheets with a high fraction of exposed {001} facets and related high photocatalytic activity - as an alternative to bipyramidal anatase TiO2 nanoparticles mainly exposing the {101} facets. The scope of the material preparation work is the thermal reduction of residual fluorides from HF (capping agent) induced during the synthesis of TiO2 nanosheets by calcination at 873K. The analytical task consists of detection and localization of fluorine present at the surface and/or in the bulk of TiO2 nanosheets before and after calcination by SEM/EDX, Auger electron spectroscopy and ToF-SIMS. T2 - Microscopy & Microanalysis 2017 Meeting CY - St. Louis, MO, USA DA - 06.08.2017 KW - Nanoplatelets KW - Fluorine KW - SEM/EDX KW - Auger electron spectroscopy KW - ToF-SIMS KW - TiO2 PY - 2017 AN - OPUS4-41579 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Abbas, Ioana M. A1 - Hoffmann, Holger A1 - Weller, Michael G. A1 - Montes-Bayon, M. T1 - Analytical strategies for the clinical assessment of the peptide hepcidin-25, a potential diagnostic tool in iron related disorders N2 - Hepcidin-25 has attracted much attention ever since its discovery in 2001. It is widely recognized that this liver produced peptide hormone plays a major role in the regulation of iron levels in mammals and can reveal important clinical information about several pathological states in patients suffering from iron-related disorders. With the aim to tackle the current difficulties in hepcidin quantification and improve the status of this promising biomarker in the clinical field, we developed a rapid and robust analytical strategy for the quantification of hepcidin-25 in human samples based on HPLC-MS/MS (QqQ) to be implemented in routine laboratories. The novelty of the method is the use of special HPLC vials to avoid adsorptive losses due to the basic character of the peptide that causes interaction with the silanol groups of the vial’s glass surface. Up to 90% decrease in the MS/MS signal was observed, when commercial HPLC vials were used, while vials treated with 3-(2-aminoethylamino)propylmethyl-dimethoxysilane or 1H,1H,2H,2H-perfluorooctyltriethoxysilane, leading to no significant losses in the dynamic range of physiological hepcidin-25 mean serum levels (10-20 µg/L). Careful analytical validation was performed for determining the reproducibility, repeatability, limit of quantification (0.5 µg/L) and linearity (0.5-40 µg/L) of the method. Serum samples from 9 healthy volunteers were analyzed with a median hepcidin-25 level of 3.3 µg/L, comparable to results reported in the literature. T2 - Australian Peptide Conference 2017 CY - Noosa Heads, Australia DA - 15.10.2017 KW - Validation KW - Hepcidin-25 KW - LC-MS/MS quantification PY - 2017 AN - OPUS4-44614 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg A1 - Madkour, Sherif A1 - Lippitz, Andreas A1 - Schönhals, Andreas A1 - Unger, Wolfgang T1 - Anomalous surface composition in thin films of a poly(vinyl methyl ether) / polystyrene blend N2 - Highly surface-sensitive X-ray photoelectron spectroscopy at HE-SGM beamline revealed in the outermost region (< 2nm) of thin films (15 -65 nm) of PVME/PS blends a relative high amount of PS, whereas in slightly deeper regions PVME was enriched. Such enrichment of PVME in the whole near-surface region was proposed in former investigations based on conventional XPS studies. T2 - Bessy User Meeting 2017 CY - Berlin, Germany DA - 13.12.2017 KW - Energy resolved XPS KW - Depth profiling KW - Thin films KW - Polymer blends PY - 2017 AN - OPUS4-43443 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - König, Markus A1 - Grohmann, Maria A1 - Niederleithinger, Ernst T1 - Anwendung der Reverse-Time Migration auf Ultraschall-Echo-Daten zur Detektion von verdeckten Rissen in Betonkörpern N2 - Das Ultraschall-Echo-Verfahren ist eine wichtige Methode der zerstörungsfreien Prüfung (ZfP). Prüfaufgaben im Bauwesen beinhalten unter anderem die korrekte Dickenbestimmung von Konstruktionen, sowie die Lokalisierung von Einbauteilen und Fehlstellen. Das Abbildungsverfahren RTM (Reverse Time Migration) liefert oft bessere Bilder als konventionelle Verfahren. Die Datenaufnahme am Betonprobekörper erfolgte mit einem Scannersystem der BAM, bei dem jeweils ein Ultraschall-Prüfkopf als Sender bzw. Empfänger diente. Es wurden senkrecht zur Profilrichtung horizontal polarisierte Scherwellen genutzt. Die RTM wurde mit dem Softwarepaket Madagascar gerechnet. Die Ergebnis zeigt das Potential dieser Methode im Bezug auf komplexe Strukturen. Die lateralen Positionen der Risse im RTM-Bild sowie deren Höhe innerhalb des Probekörpers, entsprechen recht genau dem visuellen Befund. T2 - 77. Jahrestagung der Deutschen Geophysikalischen Gesellschaft CY - Potsdam, Germany DA - 27.03.2017 KW - Ultraschall KW - Beton KW - Riss KW - Reverse Time Migration PY - 2017 AN - OPUS4-39662 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bremser, Wolfram A1 - Paul, Andrea T1 - Approaches to measurement uncertainty estimates for nominal properties N2 - Qualitative reference materials (RM) cover a wide range of the overall RM market. Proficiency testing providers attract up to a thousand of participants in PT schemes purely oriented on qualitative results. The RM used for these kinds of PT are poorly regulated, nevertheless with a more and more general acceptance of accreditation in the field of RM production and PT provision, there is an ever increasing interest in assessing producers and providers according to rules already well accepted in the field of quantitative analysis. The basic governing document, ISO 17034:2016, is written in a form that, at least for the overwhelming majority of requirements, may be applied to both qualitative and quantitative RM. However, problems remain. In particular, the expression of uncertainty of a purely qualitative result is still unresolved, and under discussion, the latter now lasting already dozens of years. Some handles would be needed. In the poster, existing approaches and some pragmatic, new ways to tackle the problem are displayed and discussed. T2 - Advanced Mathematical and Computational Tools for Metrology; AMCTM (XI) CY - Glasgow, Scotland, UK DA - 29 August 2017 KW - Nominal properties KW - Qualitative RM PY - 2017 AN - OPUS4-42467 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tütken, T. A1 - Tatzel, Michael A1 - Vogl, Jochen A1 - Rosner, M. T1 - Assessing δ26Mg in bioapatite as proxy for faunivory N2 - Knowledge about feeding behavior is essential to determine trophic interactions and reconstruct predator-prey relationships in modern and past foodwebs. Traditionally, nitrogen isotopes (δ15N) of collagen are used to quantify the ingestion of animal protein, however collagen usually does not preserve over geological time scales. To infer the diet of extinct vertebrates from fossil material more resistant dietary proxies such as Ca and Mg isotopes are needed, which are major elements in the bioapatite of bones and teeth. Magnesium is a bio-essential element that replaces calcium in the bioapatite lattice and bone and enamel δ26Mg values of extant mammals increase systematically along the foodchain [1, 2]. The existing δ26Mg data, however, is scarce, in particular with respect to carnivores, thus still limiting the capability of this dietary proxy to reliably determine trophic differences between plant- and animal-feeders. To better constrain trophic-level effects recorded in Mg isotopes, we analyzed δ26Mg of bioapatite from modern mammals with a focus on faunivores, both carnivores and as yet unexplored insectivores. The trophic level effect of δ26Mg is influenced by the geological substrate which causes isotope variability in δ26Mg of faunal remains between different ecosystems [1, 2]. Therefore, as first-order proxy for sample provenance and to assess potential influences of the bedrock substrate of the animals´ habitats on δ26Mg of bones and teeth, we measured the 87Sr/86Sr on the same specimens. This information will enable us to refine trophic level effects and determine whether δ26Mg can be used to distinguish different faunivores isotopically. This will be of paramount importance for dietary reconstructions of trophic niches in fossil foodwebs. [1] Martin et al. (2014) Geochmica Cosmochimica Acta 130, 12-20. [2] Martin et al. (2015) Proceedings of the National Academy of Sciences 112, 430-435. T2 - Goldschmidt CY - Paris, France DA - 13.08.2017 KW - Magnesium stable isotopes KW - Isotope fractionation KW - Trophic level KW - 87Sr/86Sr KW - Provenance PY - 2017 AN - OPUS4-41535 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wander, Lukas A1 - Kern, Simon A1 - Meyer, Klas A1 - Guhl, Svetlana A1 - Maiwald, Michael T1 - Assessment and validation of various flow cell designs for quantitative online NMR spectroscopy N2 - Compact nuclear magnetic resonance (NMR) instruments make NMR spectroscopy and relaxometry accessible in industrial and harsh environments for reaction and process control. Robust field integration of NMR systems have to face explosion protection or integration into process control systems with short set-up times. This paves the way for industrial automation in real process environments. The design of failsafe, temperature and pressure resistant flow through cells along with their NMR-specific requirements is an essential cornerstone to enter industrial production plants and fulfill explosion safety requirements. NMR-specific requirements aim at full quantitative pre-magnetization and acquisition with maximum sensitivity while reducing sample transfer times and dwell-times. All parameters are individually dependent on the applied NMR instrument. Luckily, an increasing number of applications are reported together with an increasing variety of commercial equipment. However, these contributions have to be reviewed thoroughly. The performance of sample flow cells commonly used in online analytics and especially for low-field NMR spectroscopy was experimentally and theoretically investigated by 1H-NMR experiments and numerical simulations. Here, we demonstrate and discuss an automated test method to determine the critical parameters of flow through cells for quantitative online NMR spectroscopy. The setup is based on randomized setpoints of flow rates in order to reduce temperature related effects. Five flow cells and tubings were assessed and compared for high-field as well as low-field NMR spectrometers. T2 - Small Molecule NMR Conference (SMASH) CY - Baveno, Italy DA - 17.09.2017 KW - Online NMR spectroscopy KW - Reaction monitoring KW - Flow cell KW - Process control KW - SMASH PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-419485 UR - http://www.smashnmr.org/conference/program AN - OPUS4-41948 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -