TY - JOUR A1 - Eißler, A. A1 - Kläring, P. A1 - Emmerling, Franziska A1 - Braun, T. T1 - Alpha-dialdimine complexes of rhodium(I) and iridium(I): Their reactivity with dioxygen and dihydrogen N2 - The rhodium(I) and iridium(I) complexes [M(Cl){ArN=C(H)C(H)=NAr}(CNtBu)] (1: M = Rh, Ar = 2,6-iPr2C6H3; 2: M = Rh, Ar = Mes; 3: M = Ir, Ar = Mes; Mes = 2,4,6-Me3C6H2) have been prepared by the reaction of [M(µ-Cl)(coe)2]2 (M = Rh, Ir; coe = cyclooctene) with the α-dialdimines ArN=C(H)C(H)=NAr (Ar = 2,6-iPr2C6H3, Mes) in thf, followed by the addition of CNtBu. XANES spectra and DFT calculations on 2 and 3 suggest an oxidation state +I at the metal centers. Treatment of the complexes 2 and 3 with O2 or 18O2 gave the peroxido complexes [M(Cl)(O2){MesN=C(H)C(H)=NMes}(CNtBu)] (4a: M = Rh; 5a: M = Ir) and [M(Cl)(18O2){MesN=C(H)C(H)=NMes}(CNtBu)] (4b: M = Rh; 5b: M = Ir). The reaction of 3 with dihydrogen resulted in the formation of the iridium dihydrido complex [Ir(Cl)(H)2{MesN=C(H)C(H)=NMes}(CNtBu)] (6a). Two isomeric α-imine-amine complexes [Ir(Cl)(H)2{MesN(H)CH2C(H)=NMe}(CNtBu)] (7/7') were obtained after prolonged reaction under H2. All of the complexes were characterized by NMR and IR spectroscopy. In addition, complexes 2, 3,and 7 were characterized by X-ray crystallography. KW - Rhodium KW - Iridium KW - Aldimines KW - Peroxido ligands KW - Hydrido ligands PY - 2013 DO - https://doi.org/10.1002/ejic.201300625 SN - 1434-1948 SN - 1099-0682 VL - 2013 IS - 27 SP - 4775 EP - 4788 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-29094 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jahnke, Annika A1 - Beck, Aaron J. A1 - Becker, Richard L. A1 - Bedulina, Daria A1 - Braun, Ulrike A1 - Gerdts, Gunnar A1 - Hildebrandt, Lars A1 - Joerss, Hanna A1 - Klein, Ole A1 - Korduan, Janine A1 - Laforsch, Christian A1 - Lannig, Gisela A1 - Leslie, Heather A. A1 - Lips, Stefan A1 - Menger, Frank A1 - Nabi, Deedar A1 - Oberbeckmann, Sonja A1 - Primpke, Sebastian A1 - Pröfrock, Daniel A1 - Ramsperger, Anja F.R.M. A1 - Römerscheid, Mara A1 - Schmitt-Jansen, Mechthild A1 - Scholz-Böttcher, Barbara M. A1 - Tröppner, Oliver A1 - Wendt-Potthoff, Katrin A1 - Kühnel, Dana T1 - Perspective article: Multisectoral considerations to enable a circular economy for plastics N2 - Plastics are widely used but improper disposal and release lead to increasing global pollution, threatening environmental and human health. To address this issue, we suggest intersectoral collaboration to achieve zero plastic pollution. The outcomes of the project P-LEACH demonstrated the enormous complexity and range of potential toxic effects of plastic-associated chemicals and micro-/nanoplastics released into water from UV-weathered plastics. We initiated an intersectoral dialogue amongst scientists, manufacturers, regulators and representatives of civil society about how to alleviate the negative impacts of plastic pollution. Circular economy offers a framework for selecting non-toxic chemicals, extending product (re)use, and waste reduction, which act to alleviate pollution when applied to plastics. We suggest three measures to advance a circular economy of plastics: 1.) Increase simplicity of chemicals in virgin plastics combined with transparent information on the contents; 2.) Consider recyclability already in plastic material and product design; 3.) Foster communication through intersectoral dialogue. Major cornerstones are the provision of standardized, easy-to-use tools to characterize plastics and plastic leachates chemically and (eco)toxicologically, the enhancement of citizen awareness enabling them to make informed choices, the creation of economic incentives for manufacturers, and sector-specific regulations to provide products that safeguard environmental and human health. KW - Plastics KW - Circular economy KW - Cross-sectoral dialogue KW - Recyclability KW - Plastic-associated chemicals PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-638280 DO - https://doi.org/10.1016/j.jhazmat.2025.139326 SN - 0304-3894 VL - 496 SP - 1 EP - 9 PB - Elsevier B.V. AN - OPUS4-63828 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wander, Lukas A1 - Vianello, A. A1 - Vollertsen, J. A1 - Westad, F. A1 - Braun, Ulrike A1 - Paul, Andrea T1 - Exploratory analysis of hyperspectral FTIR data obtained from environmental microplastics samples N2 - Hyperspectral imaging of environmental samples with infrared microscopes is one of the preferred methods to find and characterize microplastics. Particles can be quantified in terms of number, size and size distribution. Their shape can be studied and the substances can be identified. Interpretation of the collected spectra is a typical problem encountered during the analysis. The image datasets are large and contain spectra of countless particles of natural and synthetic origin. To supplement existing Analysis pipelines, exploratory multivariate data analysis was tested on two independent datasets. Dimensionality reduction with principal component analysis (PCA) and uniform manifold approximation and projection (UMAP) was used as a core concept. It allowed for improved visual accessibility of the data and created a chemical two-dimensional image of the sample. Spectra belonging to particles could be separated from blank spectra, reducing the amount of data significantly. Selected spectra were further studied, also applying PCA and UMAP. Groups of similar spectra were identified by cluster analysis using k-means, density based, and interactive manual clustering. Most clusters could be assigned to chemical species based on reference spectra. While the results support findings obtained with a ‘targeted analysis’ based on automated library search, exploratory analysis points the attention towards the group of unidientified spectra that remained and are otherwise easily overlooked. KW - Microplastics KW - FTIR KW - Exploratory analysis PY - 2020 DO - https://doi.org/10.1039/c9ay02483b VL - 12 IS - 6 SP - 781 EP - 791 PB - Royal Society of Chemistry AN - OPUS4-50396 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heller, C. A1 - Altmann, Korinna A1 - Braun, U. A1 - Kerndorff, A. A1 - Bannick, C.-G. A1 - Fuchs, M. A1 - Thamsen, P. U. T1 - Garment ageing in a laundry care process under household‐like conditions N2 - This study reflects typical consumer textile washing behaviour while taking into account existing standards in the household appliance and garment industries. Two garments were washed repeatedly with artificial dirt and detergent 30 times. The collected washing water was separated using fractional filtration. Textile physical tests were used to follow property changes of the garments, the microplastic release is determined using thermoextraction/desorbtion–gas chromatography/mass spectrometry and the total organic carbon was measured as a sum parameter for the organic bonded carbon. This article shows the importance of a reality‐based approach when investigating microplastics of textile origin in the laundry care process. Deposits of detergent and dirt on the textiles were detected. The total mass of sieve residues was much higher than the release of synthetic polymers. The cotton content of the garments causes a much higher fibre release than synthetic fibres. Both will lead to false results by purely gravimetric analysis because nonpolymer fibres will be included microplastic mass. The results cannot be generalised only by the main polymer type, knowledge of the textile construction must be included for final evaluation. KW - Fibre release KW - Microplastics KW - TED-GC/MS KW - Washing machine PY - 2023 DO - https://doi.org/10.1002/appl.202200086 SP - 1 EP - 8 PB - Wiley online library AN - OPUS4-56976 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Koshkina, Olga A1 - Westmeier, D. A1 - Lang, Thomas A1 - Bantz, C. A1 - Hahlbrock, A. A1 - Würth, Christian A1 - Resch-Genger, Ute A1 - Braun, Ulrike A1 - Thiermann, Raphael A1 - Weise, C. A1 - Eravci, M. A1 - Mohr, B. A1 - Schlaad, H. A1 - Stauber, R. H. A1 - Docter, D. A1 - Bertin, Annabelle A1 - Maskos, M. T1 - Tuning the surface of nanoparticles: Impact of poly(2-ethyl-2-oxazoline) on protein adsorption in serum and cellular uptake N2 - Due to the adsorption of biomolecules, the control of the biodistribution of nanoparticles is still one of the major challenges of nanomedicine. Poly(2-ethyl-2-oxazoline) (PEtOx) for surface modification of nanoparticles is applied and both protein adsorption and cellular uptake of PEtOxylated nanoparticles versus nanoparticles coated with poly(ethylene glycol) (PEG) and non-coated positively and negatively charged nanoparticles are compared. Therefore, fluorescent poly(organosiloxane) nanoparticles of 15 nm radius are synthesized, which are used as a scaffold for surface modification in a grafting onto approach. With multi-angle dynamic light scattering, asymmetrical flow field-flow fractionation, gel electrophoresis, and liquid chromatography-mass spectrometry, it is demonstrated that protein adsorption on PEtOxylated nanoparticles is extremely low, similar as on PEGylated nanoparticles. Moreover, quantitative microscopy reveals that PEtOxylation significantly reduces the non-specific cellular uptake, particularly by macrophage-like cells. Collectively, studies demonstrate that PEtOx is a very effective alternative to PEG for stealth modification of the surface of nanoparticles. KW - Poloxazolines KW - Protein corona KW - Cellular uptake PY - 2016 DO - https://doi.org/10.1002/mabi.201600074 SN - 1616-5187 SN - 1616-5195 VL - 16 IS - 9 SP - 1287 EP - 1300 AN - OPUS4-37369 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zarinwall, A. A1 - Waniek, Tassilo A1 - Saadat, R. A1 - Braun, U. A1 - Sturm, Heinz A1 - Garnweitner, G. T1 - Comprehensive Characterization of APTES Surface Modifications of Hydrous Boehmite Nanoparticles N2 - Hydrous boehmite (γ-AlOOH) nanoparticles (BNP) show great potential as nanoscale filler for the fabrication of fiber reinforced nanocomposite materials. Notably, the particle−matrix interaction has been demonstrated to be decisive for improving the matrix-dominant mechanical properties in the past years. Tailoring the surface properties of the nanofiller enables to selectively design the interaction and thus to exploit the benefits of the nanocomposite in an optimal way. Here, an extensive study is presented on the binding of (3-aminopropyl)triethoxysilane (APTES), a common silane surface modifier, on BNP in correlation to different process parameters (concentration, time, temperature, and pH). Furthermore, a comprehensive characterization of the modified BNP was performed by using elemental analysis (EA), thermogravimetric analysis (TGA) coupled with mass spectrometry (TGA-MS), and Kaiser’s test (KT). The results show an increasing monolayer formation up to a complete surface coverage with rising APTES concentration, time, and temperature, resulting in a maximal grafting density of 1.3 molecules/nm². Unspecific multilayer formation was solely observed under acidic conditions. Comparison of TGA-MS results with data recorded from EA, TGA, and KT verified that TGA-MS is a convenient and highly suitable method to elucidate the ligand binding in detail. KW - Boehmite KW - Nanoparticle KW - Surface KW - APTES KW - Functionalization KW - BET KW - TGA KW - Grafting KW - Nanocomposite KW - Silane PY - 2020 DO - https://doi.org/10.1021/acs.langmuir.0c02682 VL - 37 IS - 1 SP - 171 EP - 179 PB - ACS Publications AN - OPUS4-51954 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Braun, Ulrike A1 - Lorenz, Edelgard A1 - Weimann, Christiane A1 - Sturm, Heinz A1 - Karimov, I. A1 - Ettl, J. A1 - Meier, R. A1 - Wohlgemuth, W. A. A1 - Berger, H. A1 - Wildgruber, M. T1 - Mechanic and surface properties of central-venous port catheters after removal: A comparison of polyurethane and Silicon rubber materials N2 - Central venous port devices made of two different polymeric materials, thermoplastic polyurethane (TPU)and silicone rubber (SiR), were compared due their material properties. Both naïve catheters as well as catheters after removal from patients were investigated. In lab experiments the influence of various chemo-therapeutic solutions on material properties was investigated, where as the samples after removal were compared according to the implanted time inpatient. The macroscopic,mechanical performance was assessed with dynamic, specially adapted tests for elasticity. The degradation status of the materials was determined with common tools of polymer characterisation, such as infrared spectroscopy, molecular weight measurements and various methods of thermal analysis. The surface morphology was an alysed using scanning electron microscopy. A correlation between material properties and clinical performance was proposed. The surface morphology and chemical composition of the polyurethane catheter materials can potentially result in increased susceptibility of the catheter to bloodstream infections and thrombotic complications. The higher mechanic failure,especially with increasing implantation time of the silicone catheters is related to the lower mechanical performance compared to the polyurethane material as well as loss of barium sulphate filler particles near the surface of the catheter. This results in preformed microscopic notches, which act as predetermined sites of fracture. KW - Thermoplastic polyurethane (TPU) KW - Silicone rubber (SiR) KW - Catheters KW - Central venous access port KW - Complication KW - Structure propertyrelationship KW - Mechanical testing PY - 2016 DO - https://doi.org/10.1016/j.jmbbm.2016.08.002 SN - 1751-6161 SN - 1878-0180 VL - 64 SP - 281 EP - 291 PB - Elsevier Ltd. AN - OPUS4-37178 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lackmann, C. A1 - Velki, M. A1 - Šimić, A. A1 - Müller, Axel A1 - Braun, U. A1 - Ečimović, S. A1 - Hollert, H. T1 - Two types of microplastics (polystyrene-HBCD and car tire abrasion) affect oxidative stress-related biomarkers in earthworm Eisenia andrei in a time-dependent manner N2 - Microplastics are small plastic fragments that are widely distributed in marine and terrestrial environments. While the soil ecosystem represents a large reservoir for plastic, research so far has focused mainly on the impact on aquatic ecosystems and there is a lack of information on the potentially adverse effects of microplastics on soil biota. Earthworms are key organisms of the soil ecosystem and are due to their crucial role in soil quality and fertility a suitable and popular model organism in soil ecotoxicology. Therefore, the aim of this study was to gain insight into the effects of environmentally relevant concentrations of microplastics on the earthworm Eisenia andrei on multiple levels of biological organization after different exposure periods. Earthworms were exposed to two types of microplastics: (1) polystyrene-HBCD and (2) car tire abrasion in natural soil for 2, 7, 14 and 28 d. Acute and chronic toxicity and all subcellular investigations were conducted for all exposure times, avoidance behavior assessed after 48 h and reproduction after 28 d. Subcellular endpoints included enzymatic biomarker responses, namely, carboxylesterase, glutathione peroxidase, acetylcholinesterase, glutathione reductase, glutathione S-transferase and catalase activities, as well as fluorescence-based measurements of oxidative stress-related markers and multixenobiotic resistance activity. Multiple biomarkers showed significant changes in activity, but a recovery of most enzymatic activities could be observed after 28 d. Overall, only minor effects could be observed on a subcellular level, showing that in this exposure scenario with environmentally relevant concentrations based on German pollution levels the threat to soil biota is minimal. However, in areas with higher concentrations of microplastics in the environment, these results can be interpreted as an early warning signal for more adverse effects. In conclusion, these findings provide new insights regarding the ecotoxicological effects of environmentally relevant concentrations of microplastics on soil organisms. KW - Microplastics KW - Earthworms KW - Toxicity KW - Biomarker KW - oxidative stress PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-545423 DO - https://doi.org/10.1016/j.envint.2022.107190 VL - 163 SP - 1 EP - 12 PB - Elsevier Ltd. AN - OPUS4-54542 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Klöckner, P. A1 - Reemtsma, T. A1 - Eisentraut, Paul A1 - Braun, Ulrike A1 - Ruhl, A. S. A1 - Wagner, S. T1 - Tire and road wear particles in road environment e Quantification and assessment of particle dynamics by Zn determination after density separation N2 - In this study, a method for the determination of tire and road wear particle (TRWP) contents in particulate samples from road Environment was developed. Zn was identified as the most suitable elemental marker for TRWP, due to its high concentration in tire tread and the possibility of separation from other Zn sources. The mean concentration of 21 tire samples was 8.7 ± 2.0 mg Zn/g. Before quantification in samples from road environment, TRWP were separated from the particulate matrix by density separation. Method development was conducted using shredded tread particles (TP) as a surrogate for TRWP. Recovery of TP from spiked sediment was 95 ± 17% in a concentration range of 2 - 200 mg TP/g. TP determination was not affected by other Zn containing solids or spiked Zn-salts. By adjusting the density of the separation solution to 1.9 g/cm3, more than 90% of total TRWP were separated from the sample matrix. TRWP concentrations in particulate matter collected in two road runoff treatment Systems ranged from 0.38 to 150 mg TRWP/g. Differences in quantified TRWP contents of the two Systems indicate changes in particle dynamics due to ageing and aggregation processes. The developed method allows TRWP determination in road runoff and in environments that are influenced by road traffic. The validated separation procedure can also be applied for TRWP characterization in future studies. KW - Zinc analysis KW - Microplastics KW - Tire particles PY - 2019 VL - 222 SP - 714 EP - 721 PB - Elsevier AN - OPUS4-47433 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dittmann, Daniel A1 - Ruhl, A. S. A1 - Jekel, M. A1 - Braun, Ulrike T1 - Spurenstoffadsorption an Aktivkohle – Untersuchungen mit Analysen oberhalb des Siedepunktes N2 - In diesem Beitrag wird gezeigt wie mit Thermogravimetrischen Analysen (TGA) Aktivkohleoberflächen charakterisiert werden können. Außerdem wie TGA mit Zersetzungsgasanalyse zur Untersuchung von Adsorbat-Systemen (Carbamazepin an drei verschiedenen Aktivkohlen) zur Aufklärung von Adsorptionszuständen genutzt werden kann. T2 - Wasser 2019 CY - Erfurt, Germany DA - 27.05.2019 KW - Aktivkohle KW - Adsorption KW - Carbamazepin KW - Thermogravimetrie PY - 2019 SN - 978-3-947197-11-8 SP - 98 EP - 102 AN - OPUS4-48258 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Ballach, F. A1 - Bartscher, M. A1 - Bellon, Carsten A1 - Borges de Oliveira, F. A1 - Braun, M. A1 - Dennerlein, F. A1 - Flessner, M. A1 - Fuchs, P. A1 - Günnewig, O. A1 - Hausotte, T. A1 - Hess, J. A1 - Kasperl, S. A1 - Kirschbaum, K. A1 - Li, K. A1 - Maass, N. A1 - Mayer, T. A1 - Orth, Anthony A1 - Reuter, T. A1 - Suppes, A. A1 - von Schmid, M. A1 - Weiß, D. T1 - Realistische Simulation realer Röntgencomputertomografie-Systeme mit basisqualifizierter Simulationssoftware – CTSimU2 BT - Abschlussbericht N2 - Das Förderprojekt CTSimU2 baute auf den Ergebnissen des Projektes CTSimU auf. Dieses Vorprojekt erarbeitete ein (Basis-)Qualifizierungsframework für Simulationssoftwares zur Anwendung bei der Röntgen-CT für dimensionelle Messungen. Dabei stand die ausreichende physikalische Korrektheit der Durchstrahlungssimulation im Vordergrund. Für die realitätsnahe Simulation einer CT-Anlage in einer Simulationssoftware (Digitales Modell) ist jedoch nicht nur die Korrektheit der Simulationssoftware selbst, sondern auch die Güte der Parametrisierung des realen CT-Systems in der Simulationssoftware entscheidend – dies stellte den Ausgangspunkt dar. Die Parametrisierung eines CT-Systems in einer Simulationssoftware lässt sich in vier Schritte unterteilen: nach der Datenaufnahme am realen CT-System folgt die Auswertung der aufgenommenen Daten für die Generierung allgemeiner Parameterangaben. Als letztes folgte die Übertragung der Parameter in die spezifischen Simulationssoftwares und die Validierung der resultierenden Simulationsparameter. Die Methodik der Datenaufnahme am CT und die Auswertung der Daten wurde in einem Werkzeugkasten allgemein beschrieben. Der dritte Schritt, die Umsetzung der Parameter, war softwarespezifisch und wurde beispielhaft mit den vorhandenen Simulationssoftwares durchgeführt. Die Validierung der Parameter war standardisierbar und konnte durch den entwickelten Test geleistet werden, auf dessen Basis die ausreichend korrekte Simulation einer realen Anlage beurteilt werden konnte. Endresultat des Projektes war ein Richtlinienentwurf (z. B. VDI/VDE 2630) zu diesem Test, der einen informativen Annex zum Stand der Technik bezüglich der Möglichkeiten zur Parameterbestimmung enthält. Mit einer Simulationssoftware, die die Basisqualifizierung aus CTSimU bestanden hat und einen Parameterdatensatz für ein reales CT-System enthält, der den Test aus CTSimU2 bestanden hat, können realistische Simulationen dieses CT-Systems möglich sein. KW - Computertomografie KW - Simulation KW - Dimensionelles Messen PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-641719 DO - https://doi.org/10.34657/21602 N1 - Dieses Projekt wurde durch die Förderrichtlinie WIPANO gefördert und durch das Bundesministerium für Wirtschaft und Klimaschutz (2022 -2025) finanziert. Der Projektträger Jülich verwaltet die Projekte der Förderrichtlinie WIPANO. SP - 1 EP - 22 PB - TIB Technische Informationsbibliothek CY - Hannover AN - OPUS4-64171 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ressnig, A. A1 - Corbiere, T. A1 - Lunkenbein, T. A1 - Braun, Ulrike A1 - Willinger, M. G. A1 - Antonietti, M. T1 - Decomposition synthesis of tuneable, macroporous carbon foams from crystalline precursors via in situ templating N2 - A flexible, sustainable, one-step thermal decomposition route for the synthesis of hierarchical, heteroatom doped carbon foams is presented. Task-specific semi-organic crystals combine functions for three different purposes: the carbon and heteroatom source, a foaming agent (CO2) and an in situ generable template (NaCl). Insights to the decomposition pathway were gained through FTIR/MS coupled TGA and an ultrafast out-of-furnace heating procedure and the products were analysed with (HR)SEM/TEM, EELS, FTIR, and N2 sorption. The resulting macroporous carbon foams are excellent supports for metallic nanoparticles due to their hierarchical structure, high surface area and tuneable heteroatom contents. This was demonstrated for catalytically active copper or the magnetic CoNi alloy for water purification. KW - macroporous carbon KW - thermal decomposition KW - synthesize heteroatom KW - in situ template (NaCl) PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-318641 DO - https://doi.org/10.1039/c4ta03646h SN - 2050-7496 SN - 2050-7488 VL - 2 IS - 42 SP - 18076 EP - 18081 PB - RSC CY - London [u.a.] AN - OPUS4-31864 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Altmann, Korinna A1 - Goedecke, Caroline A1 - Bannick, C.-G. A1 - Abusafia, A. A1 - Scheid, C. A1 - Steinmetz, H. A1 - Paul, Andrea A1 - Beleites, C. A1 - Braun, U. T1 - Identification of microplastic pathways within a typical European urban wastewater system N2 - In recent years, thermoextraction/desorption-gas chromatography/mass spectrometry (TED-GC/MS) has been developed as a rapid detection method for the determination of microplastics (MP) mass contents in numerous environmentally relevant matrices and, in particular, for the measurement of polymers in water samples without time-consuming sample preparation. The TED-GC/MS method was applied to investigate a typical European municipal wastewater system for possible MP masses. Such investigations are important in view of the recent revision of the Urban Wastewater Treatment Directive. Four different representative sampling sites were selected: greywater (domestic wastewater without toilet), combined sewer, and influent and effluent of a wastewater treatment plant (WWTP). All samples were collected by fractional filtration. Filtration was carried out over mesh sizes of 500, 100, 50, and in some cases, 5 µm. Polyethylene (PE), polypropylene (PP), and polystyrene (PS) were detected in all samples, with the PE fraction dominating in all cases. Styrene-butadiene rubber which serves as an indication of tire abrasion, was only found in the influent of the WWTP. The highest MP mass contents were found in the combined sewer, so MP can become a source of pollution during heavy rain events when the capacity limits of the effluent are reached, and the polluted effluent is released uncontrolled into the environment. Based on the studies, MP retention from the WWTP could be estimated to be approximately 96%. Few trends in polymer type or mass contents were detected within the different fractions of the samples or when comparing samples to each other. KW - Microplastics KW - Microplastic analysis KW - TED-GC/MS KW - Microplastic pathways KW - Mass contents PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568289 DO - https://doi.org/doi.org/10.1002/appl.202200078 SP - 1 EP - 10 PB - Wiley-VCH CY - Weinheim AN - OPUS4-56828 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Loges, A. A1 - Scholz, G. A1 - de Sousa Amadeu, Nader A1 - Jingjing, S. A1 - Emmerling, Franziska A1 - John, T. A1 - Paulus, B. A1 - Braun, T. T1 - Studies on the local structure of the F/OH site in topaz by magic angle spinning nuclear magnetic resonance and Raman spectroscopy N2 - he mutual influence of F and OH groups in neighboring sites in topaz (Al2SiO4(F,OH)2) was investigated using magic angle spinning nuclear magnetic resonance (MAS NMR) and Raman spectroscopy. The splitting of 19F and 1H NMR signals, as well as the OH Raman band, provides evidence for hydrogen bond formation within the crystal structure. Depending on whether a given OH group has another OH group or fluoride as its neighbor, two different hydrogen bond constellations may form: either OH···O···HO or F···H···O. The proton accepting oxygen was determined to be part of the SiO4 tetrahedron using 29Si MAS NMR. Comparison of the MAS NMR data between an OH-bearing and an OH-free topaz sample confirms that the 19F signal at −130 ppm stems from F− ions that take part in H···F bonds with a distance of ∼ 2.4 Å, whereas the main signal at −135 ppm belongs to fluoride ions with no immediate OH group neighbors. The Raman OH sub-band at 3644 cm−1 stems from OH groups neighboring other OH groups, whereas the sub-band at 3650 cm−1 stems from OH groups with fluoride neighbors, which are affected by H···F bridging. The integrated intensities of these two sub-bands do not conform to the expected ratios based on probabilistic calculations from the total OH concentration. This can be explained by a difference in the polarizability of the OH bond between the different hydrogen bond constellations or partial order or unmixing of F and OH, or a combination of both. This has implications for the quantitative interpretation of Raman data on OH bonds in general and their potential use as a probe for structural (dis-)order. No indication of tetrahedrally coordinated Al was found with 27Al MAS NMR, suggesting that the investigated samples likely have nearly ideal Al/Si ratios, making them potentially useful as high-density electron microprobe reference materials for Al and Si, as well as for F. KW - Topas KW - NMR KW - XRD PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-561863 DO - https://doi.org/10.5194/ejm-34-507-2022 SN - 1617-4011 VL - 34 IS - 5 SP - 507 EP - 521 PB - Copernicus Publications CY - Göttingen AN - OPUS4-56186 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dittmann, D. A1 - Saal, L. A1 - Zietschmann, F. A1 - Mai, M. A1 - Altmann, Korinna A1 - Al-Sabbagh, Dominik A1 - Schuhmann, P. A1 - Ruhl, A. A1 - Jekel, M. A1 - Braun, U. T1 - Characterization of activated carbons for water treatment using TGA‑FTIR for analysis of oxygen‑containing functional groups N2 - Water treatment with activated carbon (AC) is an established method for the removal of organic micropollutants and natu ral organic matter. However, it is not yet possible to predict the removal of individual pollutants. An appropriate material characterization, matching adsorption processes in water, might be the missing piece in the puzzle. To this end, this study examined 25 diferent commercially available ACs to evaluate their material properties. Frequently reported analyses, including N2 adsorption/desorption, CHNS(O), point of zero charge (PZC) analysis, and X-ray photoelectron spectroscopy, were conducted on a selected subset of powdered ACs. Inorganic elements examined using X-ray fuorescence and X-ray difraction spectroscopy revealed that relative elemental contents were distinctive to the individual AC’s raw material and activation procedure. This study also is the frst to use thermogravimetric analysis (TGA) coupled to Fourier-transform infrared spectroscopy (FTIR) to conduct quantitative analyses of functional surface oxygen groups (SOGs: carboxylic acid, anhydride, lactone, phenol, carbonyl, and pyrone groups) on such a large number of ACs. The comparably economical TGA method was found to provide good surrogates for the PZC by pyrolytic mass loss up to 600 ◦C (ML600), for the oxygen content by ML1000 and for the carbon content by oxidation. Mass loss profles depict the AC’s chemistry like fngerprints. Furthermore, we found that SOG contents determined by TGA-FTIR covered a wide individual range and depended on the raw material and production process of the AC. TGA and TGA-FTIR might therefore be used to identify the suitability of a particular AC for a variety of target substances in diferent target waters. This can help practitioners to control AC use in waterworks or wastewater treatment plants. KW - Adsorbtion KW - Organic contaminants KW - Temperature-programmed desorption KW - Proximate analysis KW - Principal component analysis PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-555506 DO - https://doi.org/10.1007/s13201-022-01723-2 SN - 2190-5495 VL - 12 SP - 1 EP - 13 PB - Springer CY - Berlin AN - OPUS4-55550 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Drago, C A1 - Wiesner, Yosri A1 - Braun, U A1 - Giovannozi, A A1 - Fadda, M A1 - Putzu, Mara A1 - Lorenzo, S A1 - Moscoso-Pérez, C A1 - Benismail, N A1 - Palma, C A1 - Almeida, J A1 - Mattarozzi, M A1 - Barbaresi, M A1 - Piergiovanni, M A1 - Masino, M A1 - Bianchi, F A1 - Careri, M A1 - v Bavel, B A1 - Maltseva, A A1 - Sillanpää, M A1 - Pröfrock, D A1 - Wippermann, D A1 - Altmann, Korinna T1 - Harmonisation of sample preparation for microplastic analysis: Recovery rates of tablets containing microplastics as reference material for food and environmental matrix N2 - Microplastic are found ubiquitarians in the environment and food products. Up to now, their impact of risks on health and environment is still controversially discussed, but based on the precautionary principle alone, their presence should be monitored and emission should be reduced (see here also the status of existing EU regulations ). The crucial point is not only the reduction of microplastics pollution but also the introduction of legally binding, standardized procedures for their analysis. The limited availability of certified reference material as well as absence of standard operating procedures to identify, characterize and quantify microplastics according to number and mass have generated lack of comparability between different analytical methods and laboratories; but also, the need of time-consuming development of own protocols for each laboratory. Further on, harmonisation and standardisation of microplastics analysis requires specific reference materials that are used to validate the measurement and to ensure the comparability of results. In the first step, we developed tablets of a water-soluble matrix, containing defined numbers of microplastic particles or mass contents. These can be solved in water and can be handled as reference materials in bottled drinking water without additional sample preparation. These samples can be measured, using mass-based methods as thermo-analytical methods like thermal desorption-gas chromatography-mass spectrometry (TED-GC/MS) or pyrolysis–gas chromatography–mass spectrometry (Py-GC/MS) and using umber-based methods as vibrational spectroscopy like Infrared and Raman directly after filtration. The aim of this work was to delevop standard operating procedure to measure microplastics in more complex matrices and to harmonise and compare different detection and characterization methods. In fact, these matrices require different additional treatments to allow a reliable quantification and identification of microplastics. T2 - SETAC Europe 2025 CY - Vienna, Austria DA - 11.05.2025 KW - Microplastics KW - Nanoplastics PY - 2025 AN - OPUS4-63366 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Braun, Ulrike A1 - Bannick, C.G. A1 - Szewzyk, R. A1 - Ricking, M. A1 - Schniegler, S. A1 - Obermaier, N. A1 - Barthel, A. K. A1 - Altmann, Korinna A1 - Eisentraut, Paul T1 - Development and testing of a fractionated filtration for sampling of microplastics in water N2 - A harmonization of sampling, sample preparation and detection is pivotal in order to obtain comparable data on microplastics (MP) in the environment. This paper develops and proposes a suitable sampling concept for waterbodies that considers different plastic specific properties and influencing factors in the environment. Both artificial water including defined MP fractions and the discharge of a wastewater treatment plant were used to verify the derived sampling procedure, sample preparation and the subsequent analysis of MP using thermal extraction-desorption gas chromatography - mass spectrometry (TED-GC-MS). A major finding of this paper is that an application of various particle size classes greatly improves the practical handling of the sampling equipment. Size classes also enable the TED-GC-MS to provide any data on the MP size distribution, a substantial sampling property affecting both the necessary sampling volume and the optimal sampling depth. In the artificial water with defined MP fractions, the recovery rates ranged from 80 to 110%, depending on the different MP types and MP size classes. In the treated wastewater, we found both Polyethylene and polystyrene in different size classes and quantities. KW - Microplastics KW - Sampling KW - Sampling techniques KW - Water PY - 2019 DO - https://doi.org/10.1016/j.watres.2018.10.045 SN - 0043-1354 VL - 149 SP - 650 EP - 658 PB - Elsevier AN - OPUS4-47200 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Eitzen, L. A1 - Paul, S. A1 - Braun, Ulrike A1 - Altmann, Korinna A1 - Jekel, M. A1 - Ruhl, A. T1 - The challenge in preparing particle suspensions for aquatic microplastic research N2 - The occurrence of small particles consisting of organic polymers, so-called microplastic (MP), in aquatic Environments attracts increasing interest in both public and science. Recent sampling campaigns in surface Waters revealed substantial numbers of particles in the size range from a few micrometers to a few millimeters. In order to validate sample preparation, identification and quantification and to investigate the behavior of MP particles and potential toxic effects on organisms, defined MP model particles are needed. Many studies use spherical compounds that probably behave differently compared to irregularly shaped MP found in environmental samples. However, preparation and handling of MP particles are challenging tasks and have been systematically investigated in the present study. Polystyrene (PS) as a commonly found polymer with a density slightly above that of water was selected as polymer type for milling and fractionation studies. A cryogenic ball mill proved to be practical and effective to produce particles in the size range from 1 to 200 μm. The yield of small particles increased with increasing pre-cooling and milling durations. Depending on the concentration and the size, PS particles do not completely disperse in water and particles partly creep vertically up along glass walls. Stabilized MP suspensions without use of surfactants that might harm organisms are needed for toxicological studies. The stabilization of PS particle suspensions with ozone treatment reduced the wall effect and increased the number of dispersed PS particles but increased the dissolved organic carbon concentration and changed the size Distribution of the particles. KW - Reference material KW - Microplastic PY - 2018 DO - https://doi.org/10.1016/j.envres.2018.09.008 SN - 0013-9351 SN - 1096-0953 VL - 168 SP - 490 EP - 495 PB - Elsevier AN - OPUS4-46462 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dittmann, Daniel A1 - Saal, L. A1 - Zietzschmann, F. A1 - Mai, M. A1 - Altmann, Korinna A1 - Al-Sabbagh, Dominik A1 - Ruhl, A. S. A1 - Jekel, M. A1 - Braun, U. T1 - Aktivkohlecharakterisierung als weiterer Schlüssel für Adsorptionsprognosen organischer Spurenstoffe in der vierten Reinigungsstufe N2 - In diesem Beitrag wird der Einfluss des Aktivkohleprodukts auf die Adsorption von Spurenstoffen aus Kläranlagenablauf gezeigt und diskutiert. Im zweiten Teil wird das Material Aktivkohle analytisch charakterisiert und die Eigenschaften systematisiert. Die gewonnenen Erkenntnisse werden mit Bezug zu Praxislösungen zusammengefasst. T2 - Wasser 2021 CY - Online meeting DA - 10.05.2021 KW - Aktivkohle KW - Thermogravimetrie KW - Zersetzungsgasanalyse KW - Proximatanalyse PY - 2021 SP - 373 EP - 378 AN - OPUS4-52740 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dittmann, Daniel A1 - Eisentraut, Paul A1 - Goedecke, Caroline A1 - Wiesner, Yosri A1 - Jekel, M A1 - Ruhl, A S A1 - Braun, Ulrike T1 - Specific adsorption sites and conditions derived by thermal decomposition of activated carbons and adsorbed carbamazepine N2 - The adsorption of organic micropollutants onto activated carbon is a favourable solution for the treatment of drinking water and wastewater. However, these adsorption processes are not sufficiently understood to allow for the appropriate prediction of removal processes. In this study, thermogravimetric analysis, alongside evolved gas analysis, is proposed for the characterisation of micropollutants adsorbed on activated carbon. Varying amounts of carbamazepine were adsorbed onto three different activated carbons, which were subsequently dried, and their thermal decomposition mechanisms examined. The discovery of 55 different pyrolysis products allowed differentiations to be made between specific adsorption sites and conditions. However, the same adsorption mechanisms were found for all samples, which were enhanced by inorganic constituents and oxygen containing surface groups. Furthermore, increasing the loadings led to the evolution of more hydrated decomposition products, whilst parts of the carbamazepine molecules were also integrated into the carbon structure. It was also found that the chemical composition, especially the degree of dehydration of the activated carbon, plays an important role in the adsorption of carbamazepine. Hence, it is thought that the adsorption sites may have a higher adsorption energy for specific adsorbates, when the activated carbon can then potentially increase its degree of graphitisation. KW - Aktivkohle KW - TED-GC/MS KW - Adsorption KW - Thermoanalytik PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506946 DO - https://doi.org/10.1038/s41598-020-63481-y VL - 10 IS - 1 SP - 6695 PB - Nature Publishing Group AN - OPUS4-50694 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -