TY - THES
A1 - Ecke, Alexander
T1 - Integrated Diagnostics of Pharmaceutical Contaminants in Water Supply and Management Systems
N2 - The contamination of drinking water with pharmaceuticals represents a severe health risk. In order to monitor the drinking water quality continuously and enable quick countermeasures in case of contamination, novel sensors are required. Here, immunoanalytical methods based on the binding of the analyte to highly selective antibodies can be helpful. In this work, magnetic bead-based immunoassays (MBBAs) have been developed for the detection of two relevant contaminants of drinking water: diclofenac (DCF) and amoxicillin (AMX). In case of the latter, not only the parent drug is of interest in the risk assessment but also its hydrolysis products (HPs). In a comprehensive study, the influence of external factors and intrinsic properties of the water on the rate of hydrolysis was investigated. As the hydrolysis of AMX further impacts the recognition by the antibody, a strategy to analyze samples with unknown hydrolysis degree of AMX was established employing the enzyme β-lactamase in sample preparation. For both analytes, the MBBAs enable the fast quantification with results obtained in less than one hour which represents a major improvement over conventional immunoassays like the enzyme-linked immunosorbent assay (ELISA). Compared to the respective ELISAs with the same antibodies, the MBBAs further exhibit improved analytical parameters such as a broader measurement range and lower limits of detection. Due to the magnetic properties of the beads that serve as a platform for the assays, they are suitable for the mobile and automated detection at the point-of-care. An integrated diagnostic system was designed in which electrochemical detection with chronoamperometry on a microfluidic chip allows for further miniaturization of the system to enable monitoring of the drinking water quality online in water supply pipes at waterworks.
N2 - Die Kontamination von Trinkwasser mit Arzneimitteln stellt eine ernste Gesundheitsgefahr dar. Um die Trinkwasserqualität kontinuierlich überwachen und im Falle einer Verunreinigung zeitnah reagieren zu können, sind neuartige Sensoren erforderlich. Hier können immunanalytische Methoden, die auf der Bindung des Analyten an hochselektive Antikörper beruhen, hilfreich sein. In dieser Arbeit wurden magnetpartikelbasierte Immunoassays (MBBAs) für zwei relevante Kontaminanten des Trinkwassers entwickelt: Diclofenac (DCF) und Amoxicillin (AMX). Bei letzterem erwiesen sich neben der Ausgangsverbindung auch dessen Hydrolyseprodukte (HPs) als relevant für die Gefährdungsbeurteilung. In einer umfassenden Studie wurde der Einfluss von externen Faktoren und intrinsischen Eigenschaften des Wassers auf die Hydrolysegeschwindigkeit untersucht. Da die Hydrolyse von AMX auch die Erkennung durch den Antikörper beeinflusst, wurde eine Strategie zur Analyse von Proben mit unbekanntem Hydrolysegrad von AMX unter Verwendung des Enzyms β-Lactamase in der Probenvorbereitung entwickelt. Für beide Analyten ermöglichen die MBBAs eine schnelle Quantifizierung mit Ergebnissen in weniger als einer Stunde, was eine wesentliche Verbesserung gegenüber herkömmlichen Immunoassays wie dem Enzyme-linked Immunosorbent Assay (ELISA) darstellt. Im Vergleich zu den entsprechenden ELISAs mit denselben Antikörpern weisen die MBBAs zudem verbesserte analytische Parameter auf, wie einen breiteren Messbereich und niedrigere Nachweisgrenzen. Aufgrund der magnetischen Eigenschaften der Partikel, die als Plattform für die Assays dienen, eignen sie sich für den mobilen und automatisierten Einsatz vor Ort. Ein integriertes Diagnosesystem, bei dem die elektrochemische Detektion mittels Chronoamperometrie auf einem mikrofluidischen Chip eine weitere Miniaturisierung des Systems ermöglicht, wurde entworfen, um die Überwachung der Trinkwasserqualität online in Wasserwerken zu ermöglichen.
KW - Antibiotics
KW - Immunoassay
KW - Amoxicillin
KW - Diclofenac
KW - Biosensor
KW - Antibodies
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-591901
DO - https://doi.org/10.18452/25853
SP - 1
EP - 129
CY - Berlin
AN - OPUS4-59190
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kader, A.
A1 - Snellings, J.
A1 - Adams, L. C.
A1 - Gottheil, P.
A1 - Mangarova, D. B.
A1 - Heyl, J. L.
A1 - Kaufmann, Jan Ole
A1 - Moeckel, J.
A1 - Brangsch, J.
A1 - Auer, T. A.
A1 - Collettini, F.
A1 - Sauer, F.
A1 - Hamm, B.
A1 - Käs, J.
A1 - Sack, I.
A1 - Makowski, M. R.
A1 - Braun, J.
T1 - Sensitivity of magnetic resonance elastography to extracellular matrix and cell motility in human prostate cancer cell line-derived xenograft models
N2 - Prostate cancer (PCa) is a significant health problem in the male population of the Western world. Magnetic resonance elastography (MRE), an emerging medical imaging technique sensitive to mechanical properties of biological tissues, detects PCa based on abnormally high stiffness and viscosity values. Yet, the origin of these changes in tissue properties and how they correlate with histopathological markers and tumor aggressiveness are largely unknown, hindering the use of tumor biomechanical properties for establishing a noninvasive PCa staging system.
To infer the contributions of extracellular matrix (ECM) components and cell motility, we investigated fresh tissue specimens from two PCa xenograft mouse models, PC3 and LNCaP, using magnetic resonance elastography (MRE), diffusion-weighted imaging (DWI), quantitative histology, and nuclear shape analysis. Increased tumor stiffness and impaired water diffusion were observed to be associated with collagen and elastin accumulation and decreased cell motility. Overall, LNCaP, while more representative of clinical PCa than PC3, accumulated fewer ECM components, induced less restriction of water diffusion, and exhibited increased cell motility, resulting in overall softer and less viscous properties. Taken together, our results suggest that prostate tumor stiffness increases with ECM accumulation and cell adhesion - characteristics that influence critical biological processes of cancer development.
MRE paired with DWI provides a powerful set of imaging markers that can potentially predict prostate tumor development from benign masses to aggressive malignancies in patients. Statement of significance: Xenograft models of human prostate tumor cell lines, allowing correlation of microstructure-sensitive biophysical imaging parameters with quantitative histological methods, can be investigated to identify hallmarks of cancer.
KW - Magnetic resonance elastography
KW - Quantitative histology
KW - Prostate cancer
KW - Stiffness
KW - Fluidity
KW - Apparent diffusion coefficient
KW - Collagen
KW - Elastin
KW - Nuclear shape
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-618361
DO - https://doi.org/10.1016/j.bioadv.2024.213884
SN - 2772-9508
VL - 161
SP - 1
EP - 12
PB - Elsevier
CY - Amsterdam
AN - OPUS4-61836
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mangarova, Dilyana Branimirova
A1 - Reimann, Carolin
A1 - Kaufmann, Jan Ole
A1 - Möckel, Jana
A1 - Kader, Avan
A1 - Adams, Lisa Christine
A1 - Ludwig, Antje
A1 - Onthank, David
A1 - Robinson, Simon
A1 - Karst, Uwe
A1 - Helmer, Rebecca
A1 - Botnar, Rene
A1 - Hamm, Bernd
A1 - Makowski, Marcus Richard
A1 - Brangsch, Julia
T1 - Elastin-specific MR probe for visualization and evaluation of an interleukin-1β targeted therapy for atherosclerosis
N2 - Atherosclerosis is a chronic inflammatory condition of the arteries and represents the primary cause of various cardiovascular diseases. Despite ongoing progress, finding effective anti-inflammatory therapeutic strategies for atherosclerosis remains a challenge. Here, we assessed the potential of molecular magnetic resonance imaging (MRI) to visualize the effects of 01BSUR, an anti-interleukin-1β monoclonal antibody, for treating atherosclerosis in a murine model. Male apolipoprotein E-deficient mice were divided into a therapy group (01BSUR, 2 × 0.3 mg/kg subcutaneously, n = 10) and control group (no treatment, n = 10) and received a high-fat diet for eight weeks. The plaque burden was assessed using an elastin-targeted gadolinium-based contrast probe (0.2 mmol/kg intravenously) on a 3 T MRI scanner. T1-weighted imaging showed a significantly lower contrast-to-noise (CNR) ratio in the 01BSUR group (pre: 3.93042664; post: 8.4007067) compared to the control group (pre: 3.70679168; post: 13.2982156) following administration of the elastin-specific MRI probe (p < 0.05). Histological examinations demonstrated a significant reduction in plaque size (p < 0.05) and a significant decrease in plaque elastin content (p < 0.05) in the treatment group compared to control animals. This study demonstrated that 01BSUR hinders the progression of atherosclerosis in a mouse model. Using an elastin-targeted MRI probe, we could quantify these therapeutic effects in MRI.
N2 - Atherosklerose ist eine chronische entzündliche Erkrankung der Arterien und die Hauptursache für verschiedene Herz-Kreislauf-Erkrankungen. Trotz kontinuierlicher Fortschritte ist es nach wie vor schwierig, wirksame entzündungshemmende Therapiestrategien für Atherosklerose zu finden. In dieser Studie haben wir das Potenzial der molekularen Magnetresonanztomographie (MRT) zur Visualisierung der Wirkung von 01BSUR, einem monoklonalen Anti-Interleukin-1β-Antikörper, zur Behandlung von Atherosklerose in einem Mausmodell untersucht. Männliche Apolipoprotein-E-defiziente Mäuse wurden in eine Therapiegruppe (01BSUR, 2 × 0,3 mg/kg subkutan, n = 10) und eine Kontrollgruppe (keine Behandlung, n = 10) aufgeteilt und erhielten acht Wochen lang eine fettreiche Diät. Die Plaquebelastung wurde mit einer auf Elastin ausgerichteten Kontrastmittelsonde auf Gadoliniumbasis (0,2 mmol/kg intravenös) auf einem 3-T-MRT-Scanner untersucht. Die T1-gewichtete Bildgebung zeigte ein signifikant niedrigeres Kontrast-Rausch-Verhältnis (CNR) in der 01BSUR-Gruppe (vorher: 3,93042664; nachher: 8,4007067) im Vergleich zur Kontrollgruppe (vorher: 3,70679168; nachher: 13,2982156) nach Verabreichung der Elastin-spezifischen MRT-Sonde (p < 0,05). Histologische Untersuchungen zeigten eine signifikante Verringerung der Plaque-Größe (p < 0,05) und eine signifikante Abnahme des Plaque-Elastin-Gehalts (p < 0,05) in der Behandlungsgruppe im Vergleich zu den Kontrolltieren. Diese Studie zeigte, dass 01BSUR das Fortschreiten der Atherosklerose in einem Mausmodell hemmt. Mit einer auf Elastin ausgerichteten MRT-Sonde konnten wir diese therapeutischen Effekte in der MRT quantifizieren.
KW - Atherosclerosis
KW - Molecular imaging
KW - Elastin
KW - Plaque
KW - Interleukin-1beta
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610858
DO - https://doi.org/10.1038/s41598-024-71716-5
VL - 14
IS - 1
SP - 1
EP - 11
PB - Springer Science and Business Media LLC
AN - OPUS4-61085
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Beslic, D.
A1 - Tscheuschner, Georg
A1 - Renard, B. Y.
A1 - Weller, Michael G.
A1 - Muth, Thilo
T1 - Comprehensive evaluation of peptide de novo sequencing tools for monoclonal antibody assembly
N2 - Monoclonal antibodies are biotechnologically produced proteins with various applications in research, therapeutics and diagnostics. Their ability to recognize and bind to specific molecule structures makes them essential research tools and therapeutic agents. Sequence information of antibodies is helpful for understanding antibody–antigen interactions and ensuring their affinity and specificity. De novo protein sequencing based on mass spectrometry is a valuable method to obtain the amino acid sequence of peptides and proteins without a priori knowledge. In this study, we evaluated six recently developed de novo peptide sequencing algorithms (Novor, pNovo 3, DeepNovo, SMSNet, PointNovo and Casanovo), which were not specifically designed for antibody data. We validated their ability to identify and assemble antibody sequences on three multi-enzymatic data sets. The deep learning-based tools Casanovo and PointNovo showed an increased peptide recall across different enzymes and data sets compared with spectrum-graph-based approaches. We evaluated different error types of de novo peptide sequencing tools and their performance for different numbers of missing cleavage sites, noisy spectra and peptides of various lengths. We achieved a sequence coverage of 97.69–99.53% on the light chains of three different antibody data sets using the de Bruijn assembler ALPS and the predictions from Casanovo. However, low sequence coverage and accuracy on the heavy chains demonstrate that complete de novo protein sequencing remains a challenging issue in proteomics that requires improved de novo error correction, alternative digestion strategies and hybrid approaches such as homology search to achieve high accuracy on long protein sequences.
KW - De novo peptide sequencing
KW - Bioinformatics
KW - Benchmarking study
KW - Monoclonal antibody
KW - Mass spectrometry
KW - Sequence coverage
KW - Light chains
KW - Heavy chains
KW - IgG
KW - Immunoglobulins
KW - Error correction
KW - Sequencing algorithm
KW - Preprocessing
KW - Missing fragmentation sites
KW - Deep learning-based tools
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-570363
DO - https://doi.org/10.1093/bib/bbac542
VL - 24
IS - 1
SP - 1
EP - 12
PB - Oxford University Press
AN - OPUS4-57036
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Reinmuth-Selzle, K.
A1 - Bellinghausen, I.
A1 - Leifke, A. L.
A1 - Backes, A. T.
A1 - Bothen, N.
A1 - Ziegler, K.
A1 - Weller, Michael G.
A1 - Saloga, J.
A1 - Schuppan, D.
A1 - Lucas, K.
A1 - Pöschl, U.
A1 - Fröhlich-Nowoisky, J.
T1 - Chemical modification by peroxynitrite enhances TLR4 activation of the grass pollen allergen Phl p 5
N2 - The chemical modification of aeroallergens by reactive oxygen and nitrogen species (ROS/RNS) may contribute to the growing prevalence of respiratory allergies in industrialized countries. Post-translational modifications can alter the immunological properties of proteins, but the underlying mechanisms and effects are not well understood. In this study, we investigate the Toll-like receptor 4 (TLR4) activation of the major birch and grass pollen allergens Bet v 1 and Phl p 5, and how the physiological oxidant peroxynitrite (ONOO–) changes the TLR4 activation through protein nitration and the formation of protein dimers and higher oligomers. Of the two allergens, Bet v 1 exhibited no TLR4 activation, but we found TLR4 activation of Phl p 5, which increased after modification with ONOO– and may play a role in the sensitization against this grass pollen allergen. We attribute the TLR4 activation mainly to the two-domain structure of Phl p 5 which may promote TLR4 dimerization and activation. The enhanced TLR4 signaling of the modified allergen indicates that the ONOO–-induced modifications affect relevant protein-receptor interactions. This may lead to increased sensitization to the grass pollen allergen and thus contribute to the increasing prevalence of allergies in the Anthropocene, the present era of globally pervasive anthropogenic influence on the environment.
KW - Bet v 1
KW - Birch pollen allergen
KW - Phl p 5
KW - Grass pollen
KW - Phleum pratense
KW - Betula pendula
KW - Nitration
KW - Nitrotyrosine
KW - Protein nitration
KW - Toll-like receptor 4
KW - Allergy
KW - Enhancement
KW - Oligomerization
KW - Dimerization
KW - TLR4 activation
KW - Air pollution
KW - Nitrogen oxides
KW - Inflammation
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-570298
DO - https://doi.org/10.3389/falgy.2023.1066392
VL - 4
SP - 1
EP - 7
PB - Frontiers Media SA
CY - Lausanne, Switzerland
AN - OPUS4-57029
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Tchipilov, Teodor
A1 - Meyer, Klas
A1 - Weller, Michael G.
T1 - Quantitative 1H nuclear magnetic resonance (qNMR) of aromatic amino acids for protein quantification
N2 - Hydrolysis of protein samples into amino acids facilitates the use of NMR spectroscopy for protein and peptide quantification. Different conditions have been tested for quantifying aromatic amino acids and proteins. The pH-dependent signal shifts in the aromatic region of amino acid samples were examined. A pH of 12 was found to minimize signal overlap of the four aromatic amino acids. Several aromatic compounds, such as terephthalic acid, sulfoisophthalic acid, and benzene tricarboxylic acid, were applied as internal standards. The quantification of amino acids from an amino acid standard was performed. Using the first two suggested internal standards, recovery was ~97% for histidine, phenylalanine, and tyrosine at a concentration of approximately 1 mM in solution. Acidic hydrolysis of a certified reference material (CRM) of bovine serum albumin (BSA) and subsequent quantification of Phe and Tyr yielded recoveries of 98% ± 2% and 88% ± 4%, respectively, at a protein concentration of 16 g/L or 250 µM.
KW - Amino acid analysis
KW - Aromatic amino acid analysis
KW - AAA
KW - AAAA
KW - Protein hydrolysis
KW - Hydrochloric acid
KW - Metrology
KW - Traceability
KW - NIST
KW - Reference materials
KW - Internal standard
KW - Calibration
KW - Compound-independent calibration
KW - Histidine
KW - Tyrosine
KW - Tryptophan
KW - Phenylalanine
KW - Terephthalic acid
KW - Benzene-1,3,5-tricarboxylic acid
KW - Bovine serum albumin (BSA)
KW - Quantitative protein analysis
KW - Phenylketonuria
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-570943
DO - https://doi.org/10.3390/mps6010011
VL - 6
IS - 1
SP - 1
EP - 13
PB - MDPI
CY - Basel, Schweiz
AN - OPUS4-57094
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dittmar, Stefan
A1 - Weyrauch, Steffen
A1 - Reemtsma, Thorsten
A1 - Eisentraut, Paul
A1 - Altmann, Korinna
A1 - Ruhl, Aki S.
A1 - Jekel, Martin
T1 - Settling Velocities of Tire and Road Wear Particles: Analyzing Finely Graded Density Fractions of Samples from a Road Simulator and a Highway Tunnel
N2 - The terminal settling velocity is considered the most critical parameter determining the transport of tire and road wear particles (TRWP) in aquatic environments. Nonetheless, no respective empirical data has been reported so far. In this study, particle samples from a road simulator and a highway tunnel were investigated with a validated imaging method. Different density and size fractions of both samples were measured separately, acquiring sizes and settling velocities of more than 30,000 individual particles. In addition, tire marker polymers were analyzed for each fraction via thermal extraction desorption-gas chromatography/mass spectrometry. Finally, the acquired particle data was combined according to the fractions’ estimated tire contents in order to deduce detailed probability distributions of particle size and settling velocity for the actual TRWP from both samples. Weighted by TRWP-incorporated tire mass, median diameters of 54 and 44 μm as well as median settling velocities of 0.65 and 0.22 mm/s were found for TRWP from the road simulator and highway tunnel, respectively. This study thus provides the first ever empirical data on TRWP settling velocities in water, which can be highly valuable input for modeling the environmental transport of TRWP and for dimensioning TRWP retention systems.
KW - Microplastics
KW - TED-GC/MS
KW - Sinking velocities
KW - Transport
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-635449
DO - https://doi.org/10.1021/acs.est.5c04165
SN - 0013-936X
VL - 59
IS - 26
SP - 13434
EP - 13446
PB - American Chemical Society (ACS)
AN - OPUS4-63544
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Visileanu, Emilia
A1 - Altmann, Korinna
A1 - Stepa, Raluca
A1 - Haiducu, Maria
A1 - Miclea, Paul Tiberiu
A1 - Vladu, Alina
A1 - Dondea, Felicia
A1 - Grosu, Marian Catalin
A1 - Scarlat, Razvan
T1 - Comparative Analysis of Airborne Particle Concentrations in Textile Industry Environments Throughout the Workday
N2 - This paper addresses the growing concern surrounding microplastic pollution, particularly within the textile industry, and the associated potential health risks linked to the inhalation and ingestion of microplastic particles. Microplastics, defined as plastic particles smaller than five millimeters, are increasingly found not only in aquatic environments, but also in soils, air, and food. Although research on the health impacts of microplastics is still emerging, early studies indicate that these particles could contribute to health issues, including oxidative stress, inflammation, and cardiovascular diseases. Notably, individuals with higher concentrations of plastics in arterial plaques are more susceptible to heart attacks and strokes. In the textile industry, synthetic fibers such as polyester, nylon, and acrylic release microplastics into the air during production. The paper discusses a study conducted in a textile company that processes polyester yarns, where airborne microplastic concentrations were measured at various locations throughout the day. Particle sizes ranging from 0.3 nm to 10 nm were analyzed, revealing the presence of polyester polymers in the particulate matter. These findings underscore the widespread nature of microplastic pollution, particularly in industrial settings, and raise concerns about the health risks associated with prolonged exposure to airborne microplastics. While further research is necessary to fully understand the extent of these health impacts, preliminary data suggest a troubling link between microplastic inhalation and cardiovascular conditions.
KW - Microplastics
KW - Textiles
KW - Airborne particles
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-635269
DO - https://doi.org/10.3390/microplastics4020034
SN - 2673-8929
VL - 4
IS - 2
SP - 1
EP - 17
PB - MDPI AG
AN - OPUS4-63526
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Liu, F.
A1 - Reinmuth-Selzle, K.
A1 - Lai, S.
A1 - Weller, Michael G.
A1 - Pöschl, U.
A1 - Kampf, C. J.
T1 - Simultaneous determination of nitrated and oligomerized proteins by size exclusion high-performance liquid chromatography coupled to photodiode array detection
N2 - Chemical modifications such as nitration and cross-linking may enhance the allergenic potential of proteins. The kinetics and mechanisms of the underlying chemical processes, however, are not yet well understood. Here, we present a size-exclusion chromatography/spectrophotometry method (SEC-HPLC-DAD) that allows a simultaneous detection of mono-, di-, tri-, and higher protein oligomers, as well as their individual nitration degrees (NDs). The ND results of proteins from this new method agree well with the results from an alternative well-established method, for the analysis of tetranitromethane (TNM)- and nitrogen dioxide and ozone (NO2/O3)-nitrated protein samples. Importantly, the NDs for individual oligomer fractions can be obtained from the new method, and also, we provide a proof of principle for the calculation of the concentrations for individual protein oligomer fractions by their determined NDs, which will facilitate the investigation of the kinetics and mechanism for protein tyrosine nitration and cross-linking.
KW - Size exclusion chromatography
KW - HPLC-DAD
KW - Protein nitration degree
KW - Protein oligomer analysis
KW - Nitrotyrosine
KW - Dimer
KW - Trimer
KW - Oligomer
KW - Protein
KW - Tetranitromethane
KW - BSA
KW - Albumin
KW - Air pollution
KW - Nitrogen oxides
PY - 2017
UR - http://www.sciencedirect.com/science/article/pii/S0021967317303795
DO - https://doi.org/10.1016/j.chroma.2017.03.015
SN - 0021-9673
VL - 1495
SP - 76
EP - 82
PB - Elsevier B.V.
CY - Amsterdam
AN - OPUS4-40304
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Weller, Michael G.
T1 - Trennschärfe: Robustheit, Selektivität und Spezifität
N2 - Zusammenfassung Selektivität
1. Widersprüchliche Definitionen in unterschiedlichen Bereichen
2. Analytische Definition (pragmatisch): Selektivität ist die Fähigkeit einer Methode zur Unterscheidung aller interessierender Stoffe in der Probe.
3. Tests: Blindwerte, Leerwerte, Blank Values; Peakform
4. Wichtige Einflussgrößen: Trennleistung, Auflösung, Peakkapazität, Trennkapazität
5. Verbesserung durch: Kopplungsverfahren, Änderung der chromatographischen „Selektivität“, Orthogonalität
6. Wichtig ist auch die Komplexität der Probe(n)
7. Selektivität in der Immunchemie/Biochemie wird oft als Kreuzreaktion gemessen.
Zusammenfassung Robustheit
1. Sehr individuelle Kriterien – sinnvolle Auswahl notwendig!
2. Wichtige Testphasen:
a)Änderung von Methodenparametern
b)Stabilität über die Zeit
c)Überführung in die Routine
3. Ringversuche bzw. Laborvergleichsmessungen
4. Wichtigstes Vergleichskriterium: Relative Verfahrensstandardabweichung
5. Extratipp: Maximale Diversität der Testproben sicherstellen (besonders bezüglich der Matrix)
T2 - BAM Sommerschule 2016 "Qualitätssicherung in der analytischen Chemie"
CY - Berlin, Germany
DA - 04.07.2016
KW - Selektivität
KW - Spezifität
KW - Robustheit
KW - Sommerschule
KW - Blindwert
KW - Peakkapazität
KW - Kreuzreaktion
PY - 2016
AN - OPUS4-37760
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Canning, S.
A1 - Voskuil, J.
A1 - Weller, Michael G.
T1 - An author and reviewer in conversation – reproducibility and antibody validation
N2 - A recent Opinion Article by Jan Voskuil (JV), Aeonian Biotech, discussed the challenges in validation of research antibodies. It was openly peer reviewed by Michael Weller (MW), Federal Institute for Materials Research and Testing (BAM), Germany. In this blog, both discuss these challenges, the reproducibility crisis and open data.
DA - 19 May, 2017
KW - Antibodies
KW - Monoclonal
KW - Antibody ID
KW - Quality control
KW - Open data
KW - Reproducibility
KW - Peer review
PY - 2017
UR - https://blog.f1000.com/2017/05/19/an-author-and-reviewer-in-conversation-reproducibility-and-antibody-validation
SN - 2051-9796
SP - 1
EP - 5
PB - F1000 Research Ltd.
CY - London
AN - OPUS4-40310
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Abbas, Ioana M.
T1 - HPLC-MS/MS quantification of hepcidin-25, a new promising iron biomarker, in human serum samples
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. Hepcidin levels could reveal important clinical information about several pathological states in patients suffering from iron-related disorders such as chronic kidney disease (CKD) or hereditary haemochromatosis (HH). Despite significant efforts though, the development of a reliable assay to quantify hepcidin proved to be problematic for the last 15 years.
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 - Tag der Chemie 2017
CY - Berlin, Germany
DA - 05.07.2017
KW - Hepcidin-25
KW - LC-MS/MS
KW - Iron biomarker
PY - 2017
AN - OPUS4-41193
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Schwaar, Timm
T1 - Particle-based epitope analysis of a monoclonal antibody
N2 - A method for the examination of the epitope of a monoclonal antibody against a peptide related to hepcidin-25, known as a biomarker in the ion metabolism, was developed. Characterizing the exact binding site helps to understand the properties of the antibody. A peptide consists of different amino acids, each contributing differently to the binding strength. To examine the influence of the amino acids, each amino acid was subsequently exchanged by glycine. If the respective amino acid is critical for binding to the antibody, a significant drop in the binding affinity should be observed.
The epitope screening of monoclonal antibodies is a complex and elaborate procedure. For this approach, variants of the peptides were synthesized by conventional Fmoc-based peptide synthesis. The solid support was chosen to be suitable for the synthesis and additional screening against the antibody. To determine the binding affinity, the bead-bound peptides were incubated with a fluorophore-labeled antibody. After the incubation, the beads were placed on a slide and the fluorescence was detected by a fluorescence scanner. A high fluorescence indicates a high binding affinity and vice versa.
T2 - Tag der Chemie 2017
CY - Berlin, Germany
DA - 05.07.2017
KW - Antibody
KW - Epitope analysis
PY - 2017
AN - OPUS4-41191
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Paul, Martin
T1 - Microarrays for the screening of monoclonal antibodies from supernatants
N2 - In this thesis a protocol based on a direct competitive and non-competitive immunoassay using the microarray format was developed to screen emulated hybridoma supernatants against the drug carbamazepine (CBZ). As support, epoxy slides were manufactured by coating microscope glass slides with epoxy silanes. The manufactured epoxy slides showed similar capacity for protein immobilization as commercially available NEXTERION slides, but showed a higher autofluorescence background. On the epoxy slides, protein A, Cys-A, G and Cys-G were immobilized as antibody capturing coating. It could be shown that the Cys-tag considerably increased the immobilization of all compared proteins, especially of protein G. Protein Cys-G immobilized at pH 8-9 was considered the most suitable protein for antibody immobilization due to good spot uniformity and a high binding capacity for IgG. Additionally, in immobilization experiments it could be shown, that 10-500 fold excess of bovine IgG, introduced by two different fetal bovine serum (FBS) products, showed no significant competition on the immobilization of mice or goat IgG on protein Cys-G. To examine the captured antibodies for affinity to CBZ, the CBZ-TOTA-DY654 tracer was custom synthesized. It could be demonstrated, that the tracer antibody interaction was competitive with the tracer precursor, CBZ-TOTA-NH2 and CBZ. Furthermore, the synthesized tracer was also successfully used by externals to evaluate CBZ affine hybriodoma cells in flow cytometry. In the simulated screening, five antibodies with known affinity to CBZ were diluted in a cell culture medium. The screening method allowed to differentiate between affine antibodies (IC50 < 20 µg/ml) and unaffine antibodies (IC50 > 20 µg/ml), when concentrations of 0.1 µg/ml IgG or greater have been used. Of five applied antibodies, all highly affine clones (CE2 and B3212M) were reported as positives while no false-positive samples were observed. The screening included competitive, with around 89500 fold excess of CBZ, and non-competitive tracer incubation on different segments of the same chip, which resulted in total signal suppression on the competitive segment. The screening was performed in 20 hours, only a few nanoliters, of each simulated supernatant, were consumed in the screening process, furthermore in the method standard 96 well MTPs were used and no cleanroom facilities were required.
KW - Carbamazepine
KW - Microscopic slides
KW - Protein A cys
KW - Competition
KW - Epoxy silanes
KW - Supernatant
KW - Antibody immobilization
PY - 2017
SP - 1
EP - 96
PB - Humboldt-Universität zu Berlin
CY - Berlin
AN - OPUS4-54645
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Weller, Michael G.
A1 - Schneider, Rudolf
A1 - Rurack, Knut
T1 - Mit dem Testsystem zur Probe
N2 - (Bio)chemische Sensoren ersetzen bei der Vor-Ort-Analytik die großen Messgeräte oder dienen dazu, Analyten im Verdachtsfall oder kontinuierlich zu überwachen. Das können pharmazeutische Stoffe im Abwasser sein, Aflatoxin in Milch oder Sprengstoff am Flughafen. Ein Überblick über Neuentwicklungen.
KW - Biochemische Sensoren
KW - Vor-Ort-Analytik
KW - Schnelltests
KW - Antikörper
PY - 2021
DO - https://doi.org/10.1002/nadc.20214112170
VL - 69
IS - 10
SP - 71
EP - 74
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-54003
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Paul, Martin
T1 - Development of a high-sensitivity biosensor for the quasi-continuous detection of the explosive TNT and the illegal drug cocaine
N2 - An immunofluorometric biosensor with laser-induced fluorescence detection was presented. For TNT an LOD of 60 ppb and for cocaine an LOD of 9 ppb was achieved. A swipe test was performed in less than 3 minutes. No significant cross-reactivity was observed.
T2 - 15. Interdisziplinäres Doktorandenseminar des Arbeitskreises Prozessanalytik der GDCh
CY - Online meeting
DA - 06.09.2021
KW - PETN
KW - HMX
KW - RDX
KW - Microfluidic mixing
KW - Lab-on-a-chip
KW - Affinity column
KW - Monolithic material
KW - Sintered glass
KW - Dy-654
KW - Flowcell
KW - Epifluorescence
KW - CMOS camera
KW - Diode laser
KW - Antibody screening
PY - 2021
AN - OPUS4-53329
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Tannenberg, Robert
T1 - Detection of Cardiac Troponin I with Chemiluminescence Biosensor
N2 - Cardiovascular diseases are the number one cause of death worldwide and responsible for 3.9 million deaths in Europe and over 1.8 million deaths in the European Union (2017) [1]. Cardiac Troponin I (cTnI) is part of a triple protein complex and the most important biomarker for acute events such as heart attacks. Once a heart attack occurs, the blood stream within the heart is interrupted and further oxygen supply cannot be maintained. As a result, heart cells undergo apoptosis and their proteins will be released into the blood stream. Within the project CardioMet of the European Metrology Program of Research and Innovation (EMPIR) a biosensor for online-monitoring of acute myocardial infarction by detecting cTnI is being developed.
T2 - SALSA Make and Measure 2021
CY - Online meeting
DA - 16.09.2021
KW - Sensor
KW - Luminol
KW - ECL
KW - Peroxidase
KW - Monolith
KW - Lab on a Chip
KW - EMPIR
KW - 18HTL10
KW - CardioMet
KW - Horizon 2020
PY - 2021
AN - OPUS4-53306
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Peters, Stefan
A1 - Kunkel, Benny
A1 - Cakir, Cafer Tufan
A1 - Kabelitz, Anke
A1 - Witte, Steffen
A1 - Bernstein, Thomas
A1 - Bartling, Stephan
A1 - Radtke, Martin
A1 - Emmerling, Franziska
A1 - Abdel-Mageed, Ali Mohamed
A1 - Wohlrab, Sebastian
A1 - de Oliveira Guilherme Buzanich, Ana
T1 - Time-, space- and energy-resolved in situ characterization of catalysts by X-ray absorption spectroscopy
N2 - A novel setup for dispersive X-ray absorption spectroscopy (XAS) with simultaneous resolution of space, time and energy for in situ characterization of solid materials is demonstrated.
KW - Dispersive XAS
KW - Catalysis
KW - In situ
KW - Structure analysis
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-584924
DO - https://doi.org/10.1039/d3cc03277a
SN - 1359-7345
SP - 1
EP - 4
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-58492
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wiesner, Yosri
A1 - Bednarz, Marius
A1 - Braun, Ulrike
A1 - Bannick, Claus Gerhard
A1 - Ricking, Mathias
A1 - Altmann, Korinna
T1 - A promising approach to monitor microplastic masses in composts
N2 - Inputs of plastic impurities into the environment via the application of fertilizers are regulated in Germany and the EU by means of ordinances. Robust and fast analytical methods are the basis of legal regulations. Currently, only macro- and large microplastic contents (>1 mm) are measured. Microplastics (1–1,000 µm), are not yet monitored. Thermal analytical methods are suitable for this purpose, which can determine the mass content and can also be operated fully automatically in routine mode. Thermal extraction desorption-gas chromatography/mass spectrometry (TED-GC/MS) allows the identification of polymers and the determination of mass contents in solid samples from natural environments. In accordance with the German or European Commission (EC) Fertiliser Ordinance, composting plants should be monitored for microplastic particles with this method in the future. In this context a compost plant was sampled. At the end of the rotting process, the compost was sieved and separated in a coarse (>1 mm) and a fine fraction (<1 mm). The fine fraction was processed using density separation comparing NaCl and NaI as possible salt alternative and screened for microplastic masses by TED-GC/MS with additional validation and quality assurance experiments. With TED-GC/MS total microplastics mass contents of 1.1–3.0 μg/mg in finished compost could be detected with polyethylene mainly. What differs much to the total mass of plastics in the coarse fraction with up to 60 μg/mg, which were visually searched, identified via ATR-FTIR and gravimetrically weighted.
KW - Microplastics
KW - TED-GC/MS
KW - Compost
KW - Monitoring
KW - Soil
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-586688
DO - https://doi.org/10.3389/fenvc.2023.1281558
SN - 2673-4486
VL - 4
SP - 1
EP - 12
PB - Frontiers Media
CY - Lausanne
AN - OPUS4-58668
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - THES
A1 - Schwaar, Timm
T1 - Entwicklung von multidimensionalen Hochdurchsatzmethoden zur Analyse von Partikel-basierten Peptidbibliotheken
N2 - Gegenwärtig ist das Interesse und der Bedarf von Proteinbindern insbesondere in der Biotechnik und Pharmaforschung sehr groß. Kombinatorische, Partikel-basierte (One-Bead-One-Compound) Peptidbibliotheken sind eine Technik, um selektiv bindende Proteine zu identifizieren. Allerdings beinhaltet das Screening dieser Peptidbibliotheken aufwendige Schritte, wie die Separation, Sequenzierung und Charakterisierung von identifizierten Bindern. In dieser Arbeit wurde ein Chip-System entwickelt, auf dem alle Schritte eines Screenings durchgeführt werden können. Dafür wurde ein Glasobjektträger mit einem magnetisch leitenden, doppelseitigen Klebeband versehen. Die Partikel der Bibliothek wurden durch ein Sieb aufgetragen. Dies führte zu einer geordneten Immobilisierung der Partikel auf dem Chip. Über 30.000 Partikel konnten so auf einem Chip immobilisiert werden. Für die Identifizierung von selektiven Protein-bindenden Peptiden wird die immobilisierte Peptidbibliothek mit einem Fluorophor-markierten Protein inkubiert, bindende Partikel mittels Fluoreszenzscan identifiziert und die Peptidsequenz direkt auf dem Chip mittels Matrix-Assisted-Laser-Desorption/Ionization-(MALDI)-Flugzeit-(TOF)-Massenspektroskopie (MS) bestimmt. Die Durchführung einer Abbruchsequenz-Methode erlaubt die eindeutige Bestimmung der Peptidsequenzen mit einer nahezu 100 % Genauigkeit. Die entwickelte Technologie wurde in einem FLAG-Peptid-Modell validiert. Bei dem Screening wurden neue anti-FLAG-Antikörper-bindende Peptide identifiziert. Anschließend wurden in einem Screening von ca. 30.000 Partikeln IgG-bindende Peptide mit mittleren mikromolaren Dissoziationskonstanten identifiziert. Für die Identifizierung stärkerer Binder wurde eine magnetische Anreicherung entwickelt, die dem Chip-Screening vorgeschaltet werden kann. Hiermit wurden aus ca. 1 Million gescreenter Partikel, Peptide mit Dissoziationskonstanten im niedrigen mikromolaren Bereich identifiziert.
N2 - The screening of one-bead-one-compound (OBOC) libraries is a well-established technique 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 combinatoric peptide screening traditionally involves tedious steps such as affinity selection, bead picking, sequencing and characterization. In this thesis, a high-throughput “all-on-one chip” system is presented to avoid slow and technically complex bead picking steps. Beads of a combinatorial peptide library are immobilized on a conventional glass slide equipped with an electrically conductive tape. The beads are applied by using a precision sieve, which allows the spatially ordered immobilization of more than 30,000 beads on one slide. For the target screening, the immobilized library is subsequently 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 (MS), high-affinity binders are directly and unambiguously sequenced directly from the bead. The use of an optimized ladder sequencing approach improved the accuracy of the de-novo sequencing step to 100 %. This new technique was validated by employing a FLAG-based model system. In a first step, new peptide binders for the M2 anti-FLAG monoclonal antibody were identified. Finally, this system was utilized to screen for IgG-binding peptides. The screening of about 30.000 peptides on one chip led to the identification of peptide binders in the mid micromolar range. A magnetic enrichment technique was developed to increase the number of screened beads. By combining the magnetic enrichment strategy with the chip system, 1 million beads were screened and IgG-binders in the low micromolar range were identified.
KW - Peptidbibliotheken
KW - Hochdurchsatzscreening
KW - Peptidsequenzierung
KW - Chip-Screening
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511649
DO - https://doi.org/10.18452/21793
SP - 1
EP - 153
PB - Humboldt-Universität
CY - Berlin
AN - OPUS4-51164
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - THES
A1 - Oberleitner, Lidia
T1 - Immunochemical determination of caffeine and carbamazepine in complex matrices using fluorescence polarization
N2 - Pharmacologically active compounds are omnipresent in contemporary daily life, in our food and in our environment. The fast and easy quantification of those substances is becoming a subject of global importance. The fluorescence polarization immunoassay (FPIA) is a homogeneous mix-and-read format and a suitable tool for this purpose that offers a high sample throughput. Yet, the applicability to complex matrices can be limited by possible interaction of matrix compounds with antibodies or tracer.
Caffeine is one of the most frequently consumed pharmacologically active compounds and is present in a large variety of consumer products, including beverages and cosmetics. Adverse health effects of high caffeine concentrations especially for pregnant women are under discussion. Therefore, and due to legal regulations, caffeine should be monitored. Automated FPIA measurements enabled the precise and accurate quantification of caffeine in beverages and cosmetics within 2 min. Samples could be highly diluted before analysis due to high assay sensitivity in the low μg/L range. Therefore, no matrix effects were observed.
The antiepileptic drug carbamazepine (CBZ) is discussed as a marker for the elimination efficiency of wastewater treatment plants and the dispersion of their respective effluents in surface water. The development of a FPIA for CBZ included the synthesis and evaluation of different tracers. Using the optimum tracer CBZ-triglycine-5-(aminoacetamido) fluorescein, CBZ concentrations in surface waters could be measured on different platforms: one sample within 4 min in tubes or 24 samples within 20 min on microtiter plates (MTPs). For this study, a commercially available antibody was used, which led to overestimations with recovery rates up to 140% due to high cross-reactivities towards CBZ metabolites and other pharmaceuticals.
For more accurate CBZ determination, a new monoclonal antibody was produced. In this attempt, methods for improving the monitoring during the production process were successfully applied, including feces screening and cell culture supernatant screening with FPIA. The new monoclonal antibody is highly specific for CBZ and showed mostly negligible cross-reactivities towards environmentally relevant compounds. Measurements at non-equilibrium state improved the sensitivity and selectivity of the developed FPIA due to slow binding kinetics of the new antibody. Additionally, this measure enables for CBZ determination over a measurement range of almost three orders of magnitude. The comprehensively characterized antibody was successfully applied for the development of sensitive homogeneous and heterogeneous immunoassays.
The new antibody made the development of an on-site measurement system for the determination of CBZ in wastewater possible. After comprehensive optimization, this automated FPIA platform allows the precise quantification of CBZ in wastewater samples only pre-treated by filtration within 16 min. Recovery rates of 61 to 104% were observed. Measurements in the low μg/L range are possible without the application of tedious sample preparation techniques.
Different FPIA platforms including MTPs, cuvettes and tubes were successfully applied. For the choice of the right format, the application field should be considered, e.g. desired sample throughput, usage for optimization or characterization of antibodies or if a set-up for routine measurements is sought for. For high sample throughput and optimization, FPIA performance on MTPs is advantageous. The best results for the application to real samples were obtained using kinetic FP measurements in cuvettes.
T3 - BAM Dissertationsreihe - 154
KW - Antibody
KW - Coffee
KW - ELISA
KW - Fluorophore tracer
KW - Wastewater
PY - 2016
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-392506
SN - 978-3-9818270-2-6
SN - 1613-4249
VL - 154
SP - 1
EP - 124
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-39250
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Paul, Martin
A1 - Tscheuschner, Georg
A1 - Herrmann, Stefan
A1 - Weller, Michael G.
T1 - Fast Detection of 2,4,6-Trinitrotoluene (TNT) at ppt Level by a Laser-Induced Immunofluorometric Biosensor
N2 - The illegal use of explosives by terrorists and other criminals is an increasing issue in public spaces, such as airports, railway stations, highways, sports venues, theaters, and other large buildings. Security in these environments can be achieved by different means, including the installation of scanners and other analytical devices to detect ultra-small traces of explosives in a very short time-frame to be able to take action as early as possible to prevent the detonation of such devices. Unfortunately, an ideal explosive detection system still does not exist, which means that a compromise is needed in practice. Most detection devices lack the extreme analytical sensitivity, which is nevertheless necessary due to the low vapor pressure of nearly all explosives. In addition, the rate of false positives needs to be virtually zero, which is also very difficult to achieve. Here we present an immunosensor system based on kinetic competition, which is known to be very fast and may even overcome affinity limitation, which impairs the performance of many traditional competitive assays. This immunosensor consists of a monolithic glass column with a vast excess of immobilized hapten, which traps the fluorescently labeled antibody as long as no explosive is present. In the case of the explosive 2,4,6-trinitrotoluene (TNT), some binding sites of the antibody will be blocked, which leads to an immediate breakthrough of the labeled protein, detectable by highly sensitive laser-induced fluorescence with the help of a Peltier-cooled complementary metal-oxide-semiconductor (CMOS) camera. Liquid handling is performed with high-precision syringe pumps and chip-based mixing-devices and flow-cells. The system achieved limits of detection of 1 pM (1 ppt) of the fluorescent label and around 100 pM (20 ppt) of TNT. The total assay time is less than 8 min. A cross-reactivity test with 5000 pM solutions showed no signal by pentaerythritol tetranitrate (PETN), 1,3,5-trinitroperhydro-1,3,5-triazine (RDX), and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX). This immunosensor belongs to the most sensitive and fastest detectors for TNT with no significant cross-reactivity by non-related compounds. The consumption of the labeled antibody is surprisingly low: 1 mg of the reagent would be sufficient for more than one year of continuous biosensor operation.
KW - Airport
KW - Aviation
KW - Bombs
KW - Terrorism
KW - Biosensing
KW - Continuous Sensor
KW - High-Speed
KW - Ultrasensitive
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511245
DO - https://doi.org/10.3390/bios10080089
VL - 10
IS - 8
SP - 89
PB - MDPI
CY - Basel
AN - OPUS4-51124
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Costa, Elena
A1 - Climent Terol, Estela
A1 - Gawlitza, Kornelia
A1 - Wan, Wei
A1 - Weller, Michael G.
A1 - Rurack, Knut
T1 - Optimization of analytical assay performance of antibody-gated indicator-releasing mesoporous silica particles
N2 - Antibody-gated indicator delivery (gAID) systems based on mesoporous silica nano- and microparticle scaffolds are a promising class of materials for the sensitive chemical detection of small-molecule analytes in simple test formats such as lateral flow assays (LFAs) or microfluidic chips. Their architecture is reminiscent of drug delivery systems, only that reporter molecules instead of drugs are stored in the voids of a porous host particle. In addition, the pores are closed with macromolecular “caps” through a tailored “gatekeeping” recognition chemistry so that the caps are opened when an analyte has reacted with a “gatekeeper”. The subsequent uncapping leads to a release of a large number of indicator molecules, endowing the system with signal amplification features. Particular benefits of such systems are their modularity and adaptability. With the example of the immunochemical detection of type-I pyrethroids by fluorescent dye-releasing gAID systems, the influence of several tuning modes on the optimisation of such hybrid sensory materials is introduced here. In particular, different mesoporous silica supports (from nano- and microparticles to platelets and short fibres), different functionalisation routes and different loading sequences were assessed. The materials’ performances were evaluated by studying their temporal response behaviour and detection sensitivity, including the tightness of pore closure (through the amount of blank release in the absence of analyte) and the release kinetics. Our results indicate that the better the paratope-accommodating Fab region of the antibody “cap” fits into the host material's pore opening, the better the closing/opening mechanism can be controlled. Because such materials are well-suited for LFAs, performance assessment included a test-strip format besides conventional assays in suspension. In combination with dyes as indicators and smartphones for read-out, simple analytical tests for use by untrained personnel directly at a point-of-need such as an aeroplane cabin can be devised, allowing for sensitivities down to the μg kg−1 range in <5 min with case-required selectivities.
KW - Antibody-gated indicator delivery
KW - Lateral flow assay
KW - SBA-15
KW - SBA-16
KW - Type-I pyrethroids
KW - Phenothrin
KW - Permethrin
KW - Etofenprox
KW - Amplification
KW - Biosensors
KW - Immunoassays
KW - Mesoporous particles
KW - Optical detection
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-517053
DO - https://doi.org/10.1039/d0tb00371a
VL - 8
IS - 22
SP - 4950
EP - 4961
PB - Royal Society of Chemistry
AN - OPUS4-51705
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Tscheuschner, Georg
A1 - Schwaar, Timm
A1 - Weller, Michael G.
T1 - Fast Confirmation of Antibody Identity by MALDI-TOF MS Fingerprints
N2 - Thousands of antibodies for diagnostic and other analytical purposes are on the market. However, it is often difficult to identify duplicates, reagent changes, and to assign the correct original publications to an antibody. This slows down scientific progress and might even be a cause of irreproducible research and a waste of resources. Recently, activities were started to suggest the sole use of recombinant antibodies in combination with the open communication of their sequence. In this case, such uncertainties should be eliminated. Unfortunately, this approach seems to be rather a long-term vision since the development and manufacturing of recombinant antibodies remain quite expensive in the foreseeable future. Nearly all commercial antibody suppliers also may be reluctant to publish the sequence of their antibodies, since they fear counterfeiting. De novo sequencing of antibodies is also not feasible today for a reagent user without access to the hybridoma clone. Nevertheless, it seems to be crucial for any scientist to have the opportunity to identify an antibody undoubtedly to guarantee the traceability of any research activity using antibodies from a third party as a tool. For this purpose, we developed a method for the identification of antibodies based on a MALDI-TOF MS fingerprint. To circumvent lengthy denaturation, reduction, alkylation, and enzymatic digestion steps, the fragmentation was performed with a simple formic acid hydrolysis step. Eighty-nine unknown monoclonal antibodies were used for this study to examine the feasibility of this approach. Although the molecular assignment of peaks was rarely possible, antibodies could be easily recognized in a blinded test, simply from their mass-spectral fingerprint. A general protocol is given, which could be used without any optimization to generate fingerprints for a database. We want to propose that, in most scientific projects relying critically on antibody reagents, such a fingerprint should be established to prove and document the identity of the used antibodies, as well as to assign a specific reagent to a datasheet of a commercial supplier, public database record, or antibody ID.
KW - Reproducibility
KW - Quality Control
KW - Traceability
KW - Diagnostics
KW - Hybridoma
KW - Monoclonal Antibody
KW - Recombinant Antibody
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506611
DO - https://doi.org/10.3390/antib9020008
SN - 2073-4468
VL - 9
IS - 2
SP - 1
EP - 17
PB - MDPI
CY - Basel
AN - OPUS4-50661
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ziegler, K.
A1 - Kunert, A. T.
A1 - Reinmuth-Selzle, K.
A1 - Leifke, A. L.
A1 - Widera, D.
A1 - Weller, Michael G.
A1 - Schuppan, D.
A1 - Fröhlich-Nowoisky, J.
A1 - Lucas, K.
A1 - Pöschl, U.
T1 - Chemical modification of pro-inflammatory proteins by peroxynitrite increases activation of TLR4 and NF-κB: Implications for the health effects of air pollution and oxidative stress
N2 - Environmental pollutants like fine particulate matter can cause adverse health effects through oxidative stress and inflammation. Reactive oxygen and nitrogen species (ROS/RNS) such as peroxynitrite can chemically modify proteins, but the effects of such modifications on the immune system and human health are not well understood. In the course of inflammatory processes, the Toll-like receptor 4 (TLR4) can sense damage-associated molecular patterns (DAMPs). Here, we investigate how the TLR4 response and pro-inflammatory potential of the proteinous DAMPs α-Synuclein (α-Syn), heat shock protein 60 (HSP60), and high-mobility-group box 1 protein (HMGB1), which are relevant in neurodegenerative and cardiovascular diseases, changes upon chemical modification with peroxynitrite.
For the peroxynitrite-modified proteins, we found a strongly enhanced activation of TLR4 and the pro-inflammatory transcription factor NF-κB in stable reporter cell lines as well as increased mRNA expression and secretion of the pro-inflammatory cytokines TNF-α, IL-1β, and IL-8 in human monocytes (THP-1). This enhanced activation of innate immunity via TLR4 is mediated by covalent chemical modifications of the studied DAMPs.
Our results show that proteinous DAMPs modified by peroxynitrite more potently amplify inflammation via TLR4 activation than the native DAMPs, and provide first evidence that such modifications can directly enhance innate immune responses via a defined receptor. These findings suggest that environmental pollutants and related ROS/RNS may play a role in promoting acute and chronic inflammatory disorders by structurally modifying the body's own DAMPs. This may have important consequences for chronic neurodegenerative, cardiovascular or gastrointestinal diseases that are prevalent in modern societies, and calls for action, to improve air quality and climate in the Anthropocene.
KW - Protein nitration
KW - Protein oligomerization
KW - Damage-associated molecular patterns (DAMPs)
KW - Pattern recognition receptor
KW - Anthropocene
KW - Environmental pollutants
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-517128
DO - https://doi.org/10.1016/j.redox.2020.101581
VL - 37
SP - 101581
PB - Elsevier B.V.
AN - OPUS4-51712
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Brangsch, J.
A1 - Reimann, C.
A1 - Kaufmann, Jan Ole
A1 - Adams, L. C.
A1 - Onthank, D.
A1 - Thöne-Reineke, C.
A1 - Robinson, S.
A1 - Ponader, Marco
A1 - Weller, Michael G.
A1 - Buchholz, R.
A1 - Karst, U.
A1 - Botnar, R.
A1 - Hamm, B.
A1 - Makowski, M. R.
T1 - Molecular MR-Imaging for Noninvasive Quantification of the Anti-Inflammatory Effect of Targeting Interleukin-1β in a Mouse Model of Aortic Aneurysm
N2 - Background:
Molecular-MRI is a promising imaging modality for the assessment of abdominal aortic aneurysms (AAAs). Interleukin-1β (IL-1β) represents a new therapeutic tool for AAA-treatment, since pro-inflammatory cytokines are key-mediators of inflammation. This study investigates the potential of molecular-MRI to evaluate therapeutic effects of an anti-IL-1β-therapy on AAA-formation in a mouse-model.
Methods:
Osmotic-minipumps were implanted in apolipoprotein-deficient-mice (N = 27). One group (Ang-II+01BSUR group, n = 9) was infused with angiotensin-II (Ang-II) for 4 weeks and received an anti-murine IL-1β-antibody (01BSUR) 3 times. One group (Ang-II-group, n = 9) was infused with Ang-II for 4 weeks but received no treatment. Control-group (n = 9) was infused with saline and received no treatment. MR-imaging was performed using an elastin-specific gadolinium-based-probe (0.2 mmol/kg).
Results:
Mice of the Ang-II+01BSUR-group showed a lower aortic-diameter compared to mice of the Ang-II-group and control mice (p < 0.05). Using the elastin-specific-probe, a significant decrease in elastin-destruction was observed in mice of the Ang-II+01BSUR-group. In vivo MR-measurements correlated well with histopathology (y = 0.34x-13.81, R2 = 0.84, p < 0.05), ICP-MS (y = 0.02x+2.39; R2 = 0.81, p < 0.05) and LA-ICP-MS. Immunofluorescence and western-blotting confirmed a reduced IL-1β-expression.
Conclusions:
Molecular-MRI enables the early visualization and quantification of the anti-inflammatory-effects of an IL-1β-inhibitor in a mouse-model of AAAs. Responders and non-responders could be identified early after the initiation of the therapy using molecular-MRI.
KW - Cardiovascular
KW - Molecular-MRI
KW - Magnetic resonance imaging
KW - Gadolinium-based contrast agent
KW - Elastin-specific contrast agent ESMA
KW - Gadovist
KW - Gadofosveset
KW - MR Angiography
KW - Inductively Coupled Mass Spectroscopy
KW - Element Specific Bioimaging Using Laser Ablation
KW - Visualization
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-517150
DO - https://doi.org/10.1177/1536012120961875
N1 - Geburtsname von Ponader, Marco: Wilke, M. - Birth name of Ponader, Marco: Wilke, M.
VL - 19
SP - 61875
PB - SAGE
AN - OPUS4-51715
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Climent Terol, Estela
A1 - Biyikal, Mustafa
A1 - Gröninger, Delia
A1 - Weller, Michael G.
A1 - Martínez Mánez, R.
A1 - Rurack, Knut
T1 - Multiplex‐Nachweis von Analyten auf einem einzelnen Teststreifen mit Antikörper‐gesteuerten und Indikator freisetzenden mesoporösen Nanopartikeln
N2 - Vor dem Hintergrund der einzigartigen Modularität, hohen Empfindlichkeit und Selektivität von Antikörper‐gesteuerten Indikatorfreisetzungssystemen (gAID‐Systemen) wurde hier ein Multiplex‐Assay für drei organische Explosivstoffmoleküle (TATP, TNT, PETN) entwickelt, der es erlaubt, die Analyten gleichzeitig in flüssiger Phase mit einem einzelnen Teststreifen und einem Fluoreszenzlesegerät bzw. Smartphone als Detektor in Konzentrationen bis in den unteren ppb‐Bereich in <5 min nachzuweisen. Alle drei Systeme, darunter die hier neu entwickelten Systeme für TNT und PETN, tolerieren zudem nicht nur gepufferte wässrige Modelllösungen, sondern auch komplexere Matrices. Neben einem konventionellen Teststreifen mit einem Kanal erlaubte uns die Anwendung von Wachsdrucktechnologie das Herstellen von mehrkanaligen Streifen mit vergleichbarer analytischer Leistungsfähigkeit, was das enorme Potenzial der modular aufgebauten, hybriden Biosensormaterialien im Hinblick auf eine für den Endanwender maßgeschneiderte Vor‐Ort‐Analytik unterstreicht.
KW - Multiplex
KW - Gesteuerten Nanopartikeln
KW - Explosiven
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-518431
DO - https://doi.org/10.1002/ange.202009000
SN - 1521-3757
SN - 0044-8249
VL - 132
IS - 52
SP - 24071
EP - 24078
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-51843
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Climent Terol, Estela
A1 - Biyikal, Mustafa
A1 - Gröninger, Delia
A1 - Weller, Michael G.
A1 - Martínez Mánez, R.
A1 - Rurack, Knut
ED - Climent Terol, Estela
T1 - Multiplexed Detection of Analytes on Single Test Strips with Antibody-Gated Indicator-Releasing Mesoporous Nanoparticles
N2 - Rapid testing methods for the use directly at apointof need are expected to unfold their true potential especiallywhen offering adequate capabilities for the simultaneousmeasurement of multiple analytes of interest. Considering theunique modularity,high sensitivity,and selectivity of antibody-gated indicator delivery (gAID) systems,amultiplexed assayfor three small-molecule explosives (TATP, TNT,PETN) wasthus developed, allowing to detect the analytes simultaneouslywith asingle test strip at lower ppb concentrations in the liquidphase in < 5min using afluorescence reader or asmartphonefor readout. While the TNT and PETN systems were newlydeveloped here,all the three systems also tolerated harshermatrices than buffered aqueous model solutions.Besidesasingle-track strip,the outstanding modularity of the hybridbiosensor materials in combination with strip-patterningtechnologies allowed us to obtain amultichannel strip inastraightforwardmanner,offering comparable analyticalperformance while allowing to be tailored even more to theusersneed.
KW - Multiplexing
KW - Explosives detection
KW - Gated materials
KW - Fluorescence
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-518424
DO - https://doi.org/10.1002/anie.202009000
SN - 1433-7851
SN - 1521-3773
VL - 59
IS - 52
SP - 23862
EP - 23869
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-51842
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Weller, Michael G.
T1 - The Protocol Gap
N2 - Although peer review is considered one of the main pillars of modern science, experimental methods and protocols seem to be not a rigorous subject of this process in many papers. Commercial equipment, test kits, labeling kits, previously published concepts, and standard protocols are often considered to be not worth a detailed description or validation. Even more disturbing is the extremely biased citation behavior in this context, which sometimes leads to surrogate citations to avoid low-impact journals, preprints, or to indicate traditional practices. This article describes some of these surprising habits and suggests some measures to avoid the most unpleasant effects, which in the long term may undermine the credibility of science as a whole.
KW - Validation
KW - Peer review
KW - Experiment
KW - Documentation
KW - Scientific publication
KW - Reproducibility crisis
KW - Replication crisis
KW - Trust
KW - Citation
KW - References
KW - Surrogate citations
KW - Impact
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-521440
DO - https://doi.org/10.3390/mps4010012
SN - 2409-9279
VL - 4
IS - 1
SP - 1
EP - 5
PB - MDPI
CY - Basel
AN - OPUS4-52144
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chapartegui-Arias, Ander
A1 - Raysyan, A.
A1 - Belenguer, A. M.
A1 - Jaeger, Carsten
A1 - Tchipilov, Teodor
A1 - Prinz, Carsten
A1 - Abad Andrade, Carlos Enrique
A1 - Beyer, S.
A1 - Schneider, Rudolf
A1 - Emmerling, Franziska
T1 - Tailored mobility in a zeolite imidazolate framework (ZIF) antibody conjugate
N2 - Zeolitic imidazolate framework (ZIF) hybrid fluorescent nanoparticles and ZIF antibody conjugates have been synthesized, characterized, and employed in lateral-flow immunoassay (LFIA). The bright fluorescence of the conjugates and the possibility to tailor their mobility gives a huge potential for diagnostic assays. An enzyme-linked immunosorbent assay (ELISA) with horseradish peroxidase (HRP) as label, proved the integrity, stability, and dispersibility of the antibody conjugates, LC-MS/MS provided evidence that a covalent link was established between these metal-organic frameworks and lysine residues in IgG antibodies.
KW - ZIF
KW - ELISA
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-532096
DO - https://doi.org/10.1002/chem.202100803
SN - 0947-6539
SN - 1521-3765
VL - 27
IS - 36
SP - 9414
EP - 9421
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-53209
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Heilmann, Maria
A1 - Prinz, Carsten
A1 - Bienert, Ralf
A1 - Wendt, R.
A1 - Kunkel, B.
A1 - Radnik, Jörg
A1 - Hoell, A.
A1 - Wohlrab, S.
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Emmerling, Franziska
T1 - Size-Tunable Ni–Cu Core–Shell Nanoparticles—Structure, Composition, and Catalytic Activity for the Reverse Water–Gas Shift Reaction
N2 - A facile and efficient methodology is described for the solvothermal synthesis of size-tunable, stable, and uniform NiCu core–shell nanoparticles (NPs) for application in catalysis. The diameter of the NPs is tuned in a range from 6 nm to 30 nm and to adjust the Ni:Cu ratio from 30:1 to 1:1. Furthermore, the influence of different reaction parameters on the final NPs is studied. The NPs are structurally characterized by a method combination of transmission electron microscopy, anomalous small-angle X-ray scattering, X-ray absorption fine structure, and X-ray photoelectron spectroscopy. Using these analytical methods, it is possible to elucidate a core–shell–shell structure of all particles and their chemical composition. In all cases, a depletion from the core to the shell is observed, with the core consisting of NiCu alloy, surrounded by an inner Ni-rich shell and an outer NiO shell. The SiO2-supported NiCu core–shell NPs show pronounced selectivity of >99% for CO in the catalytic reduction of CO2 to CO using hydrogen as reactant (reverse water–gas shift reaction) independent of size and Ni:Cu ratio.
KW - Nanoparticles
KW - Core-shell
KW - Catalysis
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543606
DO - https://doi.org/10.1002/adem.202101308
SN - 1438-1656
SP - 1
EP - 13
PB - Wiley VCH
AN - OPUS4-54360
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dudziak, Mateusz
A1 - Topolniak, Ievgeniia
A1 - Silbernagl, Dorothee
A1 - Altmann, Korinna
A1 - Sturm, Heinz
T1 - Long-time behavior of surface properties of microstructures fabricated by multiphoton lithography
N2 - The multiphoton lithography (MPL) technique represents the future of 3D microprinting, enabling the production of complex microscale objects with high precision. Although the MPL fabrication parameters are widely evaluated and discussed, not much attention has been given to the microscopic properties of 3D objects with respect to their surface properties and time-dependent stability. These properties are of crucial importance when it comes to the safe and durable use of these structures in biomedical applications. In this work, we investigate the surface properties of the MPL-produced SZ2080 polymeric microstructures with regard to the physical aging processes during the post-production stage. The influence of aging on the polymeric microstructures was investigated by means of Atomic Force Microscopy (AFM) and X-ray Photoelectron Spectroscopy (XPS). As a result, a time-dependent change in Young’s Modulus, plastic deformation, and adhesion and their correlation to the development in chemical composition of the surface of MPL-microstructures are evaluated. The results presented here are valuable for the application of MPL-fabricated 3D objects in general, but especially in medical technology as they give detailed information of the physical and chemical time-dependent dynamic behavior of MPL-printed surfaces and thus their suitability and performance in biological systems.
KW - Multiphoton lithography
KW - Additive manufacturing
KW - Microfabrication
KW - SZ2080 negative photo-resist
KW - Young´s modulus
KW - Aging
KW - Surface properties
KW - X-ray photoelectron spectroscopy
KW - Atomic force microscopy
KW - Force-distance-curve
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-542166
DO - https://doi.org/10.3390/nano11123285
SN - 2079-4991
VL - 11
IS - 12
SP - 1
EP - 12
PB - MDPI
CY - Basel
AN - OPUS4-54216
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Müller, Axel
A1 - Altmann, Korinna
A1 - Kocher, B.
A1 - Braun, U.
T1 - Determination of tire wear markers in soil samples and their distribution in a roadside soil
N2 - Tire wear (TW) constitutes a significant source of microplastic in terrestrial ecosystems. It is known that particles emitted by roads can have an effect up to 100 m into adjacent areas. Here, we apply for the first-time thermal extraction desorption gas chromatography-mass spectrometry (TED-GC/MS) to determine TW in soil samples by detection of thermal decomposition products of styrene-butadiene rubber (SBR), without additional enrichment. Additionally, zinc contents were determined as an elemental marker for TW. Mixed soil samples were taken along three transects along a German motorway in 0.3, 2.0, and 5.0 m distance from the road. Sampling depths were 0–2, 2–5, 5–10, and 10–20 cm. Four fine fractions, 1 000–500, 500–100, 100–50, and <50 μm, were analyzed.
TW contents based on SBR ranged from 155 to 15 898 mg kg−1. TW contents based on zinc were between 413 and 44 812 mg kg−1. Comparison of individual values of SBR and zinc reveals SBR as a more specific marker. Results confirm that most TW ends up in the topsoil within a 2 m distance.
The sampling strategy resulted in representative data for a larger area. Standard deviations of quadruple TED-GC/MS determination of SBR were <10% for all grain size fractions. TED-GC/MS is a suitable analytical tool for determining TW in soil samples without the use of toxic chemicals, enrichment, or special sample preparation.
KW - Microplastic
KW - TED-GC/MS
KW - Tire wear
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543344
DO - https://doi.org/10.1016/j.chemosphere.2022.133653
VL - 294
SP - 1
EP - 8
PB - Elsevier Ltd.
AN - OPUS4-54334
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gernhard, M.
A1 - Rautenberg, Max
A1 - Hörner, G.
A1 - Weber, B.
A1 - Emmerling, Franziska
A1 - Roth, C.
T1 - Mechanochemical Synthesis as a Greener Way to ProduceIron-based Oxygen Reduction Catalysts
N2 - Iron-based catalysts have been reported manifold and studied as platinum group metal (PGM) free alternatives for the catalysis of the oxygen reduction reaction (ORR). However, their sustainable preparation by greener synthesis approaches is usually not discussed. In this work, we propose a new method for the sustainable preparation of such catalysts by using a mechanochemical approach, with no solvents and non-toxic chemicals. The materials obtained from low temperature carbonization (700 °C) exhibit considerable and stable catalytic performance for ORR in alkaline medium. A catalyst obtained
from iron hydroxide, tryptophan, dicyandiamide, and ammonium nitrate shows the best electrocatalytic Performance with an overpotential of 921 mV vs. RHE at 0.1 mA/cm2 and an electron transfer number of 3.4.
KW - PGM-free catalyst
KW - Oxygen Reduction Reaction
KW - AEMFC
KW - Mössbauer Spectroscopy
KW - Sustainable Synthesis
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-535326
DO - https://doi.org/10.1002/zaac.202100194
VL - 647
IS - 22
SP - 2080
EP - 2087
PB - Weinheim-VCH GmbH
AN - OPUS4-53532
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mazzeo, P. P.
A1 - Prencipe, M.
A1 - Feiler, Torvid
A1 - Emmerling, Franziska
A1 - Bacchi, A.
T1 - On the mechanism of cocrystal mechanochemical reaction via low melting eutectic: A time-resolved in situ monitoring investigation
N2 - Mechanochemistry has become a sustainable and attractive cost-effective synthetic technique, largely used within the frame of crystal engineering. Cocrystals, namely, crystalline compounds made of different chemical entities within the same crystal structure, are typically synthesized in bulk via mechanochemistry; however, whereas the macroscopic aspects of grinding are becoming clear, the fundamental principles that underlie mechanochemical cocrystallization at the microscopic level remain poorly understood. Time-resolved in situ (TRIS) monitoring approaches have opened the door to exceptional detail regarding mechanochemical reactions. We here report a clear example of cocrystallization between two solid coformers that proceeds through the formation of a metastable low melting binary eutectic phase. The overall cocrystallization process has been monitored by time-resolved in situ (TRIS) synchrotron X-ray powder diffraction with a customized ball milling setup, currently available at μ Spot beamline at BESSY-II, Helmholtz-Zentrum Berlin. The binary system and the low melting eutectic phase were further characterized via DSC, HSM, and VT-XRPD.
KW - Mechanochemistry
KW - In situ
KW - Cocrystal
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-552977
DO - https://doi.org/10.1021/acs.cgd.2c00262
SN - 1528-7505
VL - 22
IS - 7
SP - 4260
EP - 4267
PB - ACS Publ.
CY - Washington, DC
AN - OPUS4-55297
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rautenberg, Max
A1 - Bhattacharya, Biswajit
A1 - Witt, Julia
A1 - Jain, Mohit
A1 - Emmerling, Franziska
T1 - In situ time-resolved monitoring of mixed-ligand metal–organic framework mechanosynthesis
N2 - The mechanism of mixed-ligand metal–organic framework (MOF) formation, and the possible role of intermediate single-ligand metal complexes during mechanosynthesis, have not been explored yet. For the first time, we report here in situ real-time monitoring of the mechanochemical formation mechanism of mixed-ligand MOFs. Our results show that binary phases can act as intermediates or competing products in one-pot and stepwise synthesis.
KW - Mechanochemistry
KW - Metal-organic-frameworks
KW - In situ X-ray diffraction
KW - Mixed-ligand MOFs
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-558167
DO - https://doi.org/10.1039/D2CE00803C
SP - 1
EP - 4
PB - Royal Society of Chemistry
AN - OPUS4-55816
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Senges, Gene
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Lindič, Tilen
A1 - Gully, Tyler A.
A1 - Winter, Marlon
A1 - Radtke, Martin
A1 - Röder, Bettina
A1 - Steinhauer, Simon
A1 - Paulus, Beate
A1 - Emmerling, Franziska
A1 - Riedel, Sebastian
T1 - Unravelling highly oxidized nickel centers in the anodic black film formed during the Simons process by in situ X-ray absorption near edge structure spectroscopy
N2 - The electrofluorination after Simons has been used for the last century to produce everyday life materials. An in situ XANES investigation of the controversially debated black film apparent in the Simons process revealed high-valent nickel centers.
KW - Synchrotron
KW - BAMline
KW - XANES
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608366
DO - https://doi.org/10.1039/d3sc06081k
SN - 2041-6520
VL - 15
IS - 12
SP - 4504
EP - 4509
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-60836
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fischer, Janina
A1 - Kaufmann, Jan Ole
A1 - Weller, Michael G.
T1 - Simple Determination of Affinity Constants of Antibodies by Competitive Immunoassays
N2 - The affinity constant, also known as the equilibrium constant, binding constant, equilibrium association constant, or the reciprocal value, the equilibrium dissociation constant (Kd), can be considered as one of the most important characteristics for any antibody–antigen pair. Many methods based on different technologies have been proposed and used to determine this value. However, since a very large number of publications and commercial datasheets do not include this information, significant obstacles in performing such measurements seem to exist. In other cases where such data are reported, the results have often proved to be unreliable. This situation may indicate that most of the technologies available today require a high level of expertise and effort that does not seem to be available in many laboratories. In this paper, we present a simple approach based on standard immunoassay technology that is easy and quick to perform. It relies on the effect that the molar IC50 approaches the Kd value in the case of infinitely small concentrations of the reagents. A two-dimensional dilution of the reagents leads to an asymptotic convergence to Kd. The approach has some similarity to the well-known checkerboard titration used for the optimization of immunoassays. A well-known antibody against the FLAG peptide, clone M2, was used as a model system and the results were compared with other methods. This approach could be used in any case where a competitive assay is available or can be developed. The determination of an affinity constant should belong to the crucial parameters in any quality control of antibody-related products and assays and should be mandatory in papers using immunochemical protocols.
N2 - Die Affinitätskonstante, auch bekannt als Gleichgewichtskonstante, Bindungskonstante, Gleichgewichtsassoziationskonstante oder der reziproke Wert, die Gleichgewichtsdissoziationskonstante (Kd), kann als eine der wichtigsten Eigenschaften für jedes Antikörper-Antigen-Paar angesehen werden. Zur Bestimmung dieses Wertes wurden zahlreiche Methoden auf der Grundlage verschiedener Technologien vorgeschlagen und verwendet. Da jedoch eine sehr große Anzahl von Veröffentlichungen und kommerziellen Datenblätter diese Information nicht enthalten, scheint es erhebliche Hindernisse bei der Durchführung solcher Messungen zu geben. In anderen Fällen, in denen solche Daten angegeben werden, haben sich die Ergebnisse häufig als unzuverlässig erwiesen. Diese Situation könnte darauf hindeuten, dass die meisten der heute verfügbaren Technologien ein hohes Maß an Fachwissen und Aufwand erfordern, das in vielen Labors nicht vorhanden zu sein scheint. In diesem Beitrag stellen wir einen einfachen Ansatz vor, der auf der Standard-Immunoassay-Technologie basiert und einfach und schnell durchführbar ist. Er beruht auf dem Effekt, dass sich der molare IC50 bei unendlich kleinen Reagenz-Konzentrationen dem Kd-Wert annähert. Eine zweidimensionale Verdünnung der Reagenzien führt zu einer asymptotischen Konvergenz zu Kd. Der Ansatz hat eine gewisse Ähnlichkeit mit der bekannten Checkerboard-Titration, die zur Optimierung von Immunoassays verwendet wird. Ein bekannter Antikörper gegen das FLAG-Peptid, Klon M2, wurde als Modellsystem verwendet, und die Ergebnisse wurden mit anderen Methoden verglichen. Dieser Ansatz kann überall dort angewendet werden, wo ein kompetitiver Assay verfügbar ist oder entwickelt werden kann. Die Bestimmung einer Affinitätskonstante sollte zu den entscheidenden Parametern bei der Qualitätskontrolle von Antikörperprodukten und -assays gehören und in Arbeiten, die immunchemische Protokolle verwenden, obligatorisch sein.
KW - ELISA
KW - Competitive immunoassay
KW - IC50
KW - Test midpoint
KW - Point of inflection
KW - Equilibrium constant
KW - Dissociation constant
KW - Binding strength
KW - Antibody antigen complex
KW - Bio-interaction
KW - SPR
KW - Surface-plasmon resonance
KW - FLAG peptide
KW - Clone M2
KW - Antibody quality
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605607
DO - https://doi.org/10.3390/mps7030049
SN - 2409-9279
VL - 7
IS - 3
SP - 1
EP - 11
PB - MDPI
CY - Basel
AN - OPUS4-60560
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Becker, Roland
A1 - Altmann, Korinna
A1 - Sommerfeld, Thomas
A1 - Braun, Ulrike
T1 - Quantification of microplastics in a freshwater suspended organic matter using different thermoanalytical methods – outcome of an interlaboratory comparison
N2 - A sedimented freshwater suspended organic matter fortified with particles of polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET) was employed in an interlaboratory comparison of thermoanalytical methods for microplastics identification and quantification. Three laboratories performed pyrolysis gas chromatography-mass spectrometry (Py-GC-MS), three others provided results using thermal extraction desorption followed by gas chromatography coupled to mass spectrometry (TED-GC-MS). One participant performed thermogravimetry-infrared spectroscopy (TGA-FTIR) and two participants used thermogravimetry coupled to mass spectrometry (TGA-MS). Further participants used differential scanning microscopy (DSC), a procedure based on micro combustion calorimetry (MCC) and a procedure based on elemental analysis.
Each participant employed a different combination of sample treatment, calibration and instrumental Settings for polymer identification and quantification. Though there is obviously room for improvements regarding the between-laboratory reproducibility and the harmonization of procedures it was seen that the participants Performing Py-GC-MS, TED-GC-MS, and TGA-FTIR were able to correctly identify all polymers and to report reasonable quantification results in the investigated concentration range (PE: 20.0 μg/mg, PP: 5.70 μg/mg; PS: 2.20 μg/mg, PET: 18.0 μg/mg). Although for the other methods limitations exists regarding the detection of specific polymers, they showed potential as alternative approaches for polymer quantification in solid environmental matrices.
KW - Interlaboratory comparison
KW - Microplastics
KW - Suspended organic matter
KW - Pyrolysis
PY - 2020
DO - https://doi.org/10.1016/j.jaap.2020.104829
VL - 148
SP - 1
EP - 6
PB - Elsevier B.V.
AN - OPUS4-50977
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Monikh, Fazel A.
A1 - Materić, Dušan
A1 - Valsami-Jones, Eugenia
A1 - Grossart, Hans-Peter
A1 - Altmann, Korinna
A1 - Holzinger, Rupert
A1 - Lynch, Iseult
A1 - Stubenrauch, Jessica
A1 - Peijnenburg, Willie
T1 - Challenges in studying microplastics in human brain
N2 - Human exposure to microplastics and nanoplastics (MNPs) is an emerging concern with potential implications for health. As awareness of this issue grows, it has prompted increasing scientific attention toward understanding if, and how, MNPs accumulate in human tissues. In a recent study, Nihart et al.1 used the analytical technique of pyrolysis gas chromatography–mass spectrometry (Py-GC–MS) to detect MNPs in human liver, kidney and brain, reporting the highest concentrations in the brain, with polyethylene as the predominant polymer. The study as reported appears to face methodological challenges, such as limited contamination controls and lack of validation steps, which May affect the reliability of the reported concentrations. In this Matters Arising, we highlight methodological limitations that have General relevance for advancing robust and reproducible MNP detection in human biomonitoring studies.
KW - Microplastics
KW - Nanoplastics
KW - Py-GC-MS
PY - 2025
DO - https://doi.org/10.1038/s41591-025-04045-3
SN - 1078-8956
VL - 31
IS - 12
SP - 1
EP - 3
PB - Springer Science and Business Media LLC
AN - OPUS4-64698
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Atanasova, Aleksandra
T1 - Herstellung und Einsatz neuartiger Trypsin-Partikel für den enzymatischen Antikörper-Verdau
N2 - In dieser Arbeit wurden zwei Trypsinvarianten, der Wildtyp (wtT) und eine thermostabile Variante (tsT), rekombinant hergestellt. Die Herstellung von Proteinen in Bakterien kann zu Fehlfaltungen und Einschlusskörperchen führen, weshalb eine geeignete Faltungsstrategie notwendig ist. In dieser Arbeit konnte eine schrittweise Vorgehensweise erfolgreich angewendet werden.
Nach der Ni-NTA-Aufreinigung wurde zusätzlich eine substratspezifische Benzamidin-Aufreinigung eingesetzt, um die Aktivität zu verbessern. Außerdem wurden die rekombinanten Trypsine auf Korund immobilisiert. Korund ist ein kostengünstiges Material, das nach Silanisierung und Glutaraldehyd-Kopplung für die Bindung von Proteinen geeignet gemacht wurde. Dabei konnte gezeigt werden, dass mehr wtT als tsT gebunden wurde, was sich auch in den Kopplungsdichte widerspiegelte.
Die immobilisierten Enzyme wurden in Bezug auf Aktivität, Wiederverwendbarkeit, Lagerfähigkeit und Temperaturstabilität untersucht. Beide Varianten zeigten vergleichbare Leistungen, wobei tsT bei höheren Temperaturen eine etwas bessere Stabilität aufwies. Für den Antikörperverdau wurden sowohl thermische als auch chemische Denaturierungen bei verschiedenen Temperaturen ( 37 °C und 60 °C) getestet. Die Analyse mit MALDI-TOF-MS zeigte, dass gute Werte für die Sequenzabdeckung erzielt werden konnten. Besonders die chemische Denaturierung führte zu besseren Ergebnissen mit weniger Selbstverdau.
Beim Vergleich mit kommerziell immobilisiertem Crude-Trypsin zeigten die rekombinanten Varianten eine höhere Spezifität und bessere Sequenzabdeckung bei gleichzeitig geringerem Selbstverdau. Die Wiederverwendbarkeit wurde durch fünf Verdauzyklen bei 37 °C überprüft. Dabei blieb die Aktivität weitgehend stabil, auch wenn die Peakintensität in den MALDI-Spektren mit jedem Zyklus abnahm. Eine eindeutige Zuordnung der Fingerprints des Antikörpers aus einer Bibliothek von über 90 Antikörpern war trotz dessen gegeben.
KW - Korund
KW - Immobilisierung
KW - Proteomik
KW - Rekombinante Proteine
KW - Thermostabile Enzyme
PY - 2025
SP - 1
EP - 86
CY - Berlin
AN - OPUS4-64433
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Béalu, Zoé
A1 - Walther, Johanna
A1 - Abusafia, Attaallah
A1 - Altmann, Korinna
A1 - Meurer, Maren
A1 - Gretzschel, Oliver
A1 - Schäfer, Michael
A1 - Steinmetz, Heidrun
T1 - Removal of Organic Micropollutants and Microplastics via Ozonation Followed by Granular Activated Carbon Filtration
N2 - Discharge from Wastewater Treatment Plants (WWTPs) can result in the emission of organic micropollutants (OMPs) and microplastics (MPs) into the aquatic environment. To prevent this harmful release, a pilot plant consisting of an ozonation followed by a granular activated carbon (GAC) filter was operated at a WWTP in Germany, and its side-effects on the concentrations of nitrogen (N) and phosphorous (P) compounds were measured. Over 80% of OMPs and transformation products were removed during the operating time (around 6000 bed volumes) no matter the ozone dose (from around 0.1 to 0.5 mgO3/mgDOC), except for Diatrizoic acid, whose breakthrough appeared at 3500 BV. Formation of the oxidation by-product, NDMA, increased with higher ozone doses, but the concentration remained below 100 ng/L. Bromate was formed at a higher ozone dose (0.4 mgO3/mgDOC) but at a low concentration—below 10 µg/L. The MP particles detected in the inflow (PE, SBR, PP, and PS) were effectively eliminated to a high degree, with a removal rate of at least 92%. Carbon parameters (COD, DOC, and SAC254) were removed further by the pilot plant, but to different extents. As expected, nitrate was formed during ozonation, while nitrite’s concentration decreased. Further, nitrite decreased and nitrate increased within the GAC filter, while ammonium was eliminated by at least 90%. Total P concentration decreased after the pilot, but the concentration of PO4-P increased.
KW - Microplastics
KW - TED-GC/MS
KW - Granular Activated Carbon Filtration
KW - Removal of Organic Micropollutants
KW - Wastewater treatment plant
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615209
DO - https://doi.org/10.3390/environments11110241
VL - 11
IS - 11
SP - 1
EP - 38
PB - MDPI AG
AN - OPUS4-61520
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fadda, Marta
A1 - Sacco, Alessio
A1 - Altmann, Korinna
A1 - Ciornii, Dmitri
A1 - Milczewski, Frank
A1 - Bañares, Miguel A.
A1 - Portela, Raquel
A1 - Giovannozzi, Andrea Mario
A1 - Rossi, Andrea Mario
T1 - Tracking nanoplastics in drinking water: a new frontier with the combination of dielectrophoresis and Raman spectroscopy
N2 - Detection of micro- (MPs) and nanoplastics (NPs) in food and environmental matrices has been gaining relevance due to their potential toxicological effects on human health. While MPs have been detected in a wide range of complex matrices, suitable methods for the characterization and chemical identification of NPs are still lacking, primarily due to significant methodological challenges associated with their nano-specific physiochemical properties, including size distribution (1 nm – 1 µm), dynamic surface chemical changes, and carbon-based composition, which complicate their detection compared to engineered nanomaterials. To overcome the traditional limitations of spectroscopic techniques in terms of spatial resolution and sensitivity at the sub-micrometer level, a novel label-free methodology is presented for specifically identifying the chemical composition of NPs directly in suspension by combining Raman spectroscopy with dielectrophoresis (DEP). Using a custom-built device, small volumes of NPs are injected into a dielectrophoretic cell and locally trapped by DEP forces to fill the Raman confocal volume, facilitating their detection and identification, and providing high signal-to-noise ratio Raman spectra for more reliable analysis. This approach was successfully applied to both Milli-Q water and a commercial brand of drinking water, enabling the rapid identification of various types of NPs with different sizes and polymer compositions at concentrations as low as 20 µg/mL. These included certified reference polystyrene beads ranging from 800 to 60 nm in diameter, as well as polydisperse NPs, more representative of real samples in terms of size distribution and polymer type, such as polyethylene (450 nm), polypropylene (180 nm), and polyethylene terephthalate (100 nm). Moreover, the chemical fingerprint of each NPs was thoroughly investigated and compared with the corresponding bulk polymers, highlighting possible changes in the Raman bands due to surface oxidation or nanometer-scale effect. Therefore, this innovative method can be considered a valuable approach for addressing gaps in the detection and identification of NPs, as well as for monitoring their dynamic phisiochemical changes in real matrices.
KW - Nanoplastics
KW - Water contaminants
KW - Raman microspectroscopy
KW - Dielectrophoresis
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-633658
DO - https://doi.org/10.1186/s43591-025-00131-y
SN - 2662-4966
VL - 5
IS - 1
SP - 1
EP - 11
PB - Springer Science and Business Media LLC
AN - OPUS4-63365
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Altmann, Korinna
A1 - Portela, Raquel
A1 - Barbero, Francesco
A1 - Breuninger, Esther
A1 - Camassa, Laura Maria Azzurra
A1 - Cirkovic Velickovic, Tanja
A1 - Charitidis, Costas
A1 - Costa, Anna
A1 - Fadda, Marta
A1 - Fengler, Petra
A1 - Fenoglio, Ivana
A1 - Giovannozzi, Andrea M.
A1 - Haugen, Øyvind Pernell
A1 - Kainourgios, Panagiotis
A1 - von der Kammer, Frank
A1 - Kirchner, Markus J.
A1 - Lomax-Vogt, Madeleine
A1 - Lujic, Tamara
A1 - Milczewski, Frank
A1 - Moussawi, Mhamad Aly
A1 - Ortelli, Simona
A1 - Parac-Vogt, Tatjana N.
A1 - Potthoff, Annegret
A1 - Reinosa, Julian J.
A1 - Röschter, Sophie
A1 - Sacco, Alessio
A1 - Wimmer, Lukas
A1 - Zanoni, Ilaria
A1 - Dailey, Lea Ann
T1 - Correction: Characterizing nanoplastic suspensions of increasing complexity: Inter-laboratory comparison of size measurements using dynamic light scattering
N2 - Correction for ‘Characterizing nanoplastic suspensions of increasing complexity: Inter-laboratory comparison of size measurements using dynamic light scattering’ by Korinna Altmann et al., Environ. Sci.: Nano, 2025, 12, 5242–5256, https://doi.org/10.1039/D5EN00645G.
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-656330
DO - https://doi.org/10.1039/d6en90001a
SN - 2051-8153
VL - 13
IS - 2
SP - 1233
PB - Royal Society of Chemistry (RSC)
CY - Cambridge
AN - OPUS4-65633
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Fünning, Tabea
A1 - Peczek, Anna
A1 - Kroh, Aleksandra
A1 - Mai, Christian
A1 - Paul, Martin
A1 - Thomsen, Florian
A1 - Tannenberg, Robert
A1 - Schumann, Christoph
A1 - Weller, Michael G.
A1 - Mai, Andreas
A1 - Steglich, Patrick C.
ED - Lieberman, Robert A.
ED - Baldini, Francesco
ED - Homola, Jiri
T1 - Optimization of local backside released micro-ring resonators for sensing applications using silicon photonic integrated circuits in a SOI technology
N2 - Photonic micro-ring resonators (MRR) are widely studied for their high sensitivity across applications like environmental monitoring, healthcare, and chemical analysis. Their evanescent field sensing requires partially unembedded waveguides compatible with CMOS processing. Our approach uses local backside etching with an additional buried oxide (BOX) etch to release waveguides while preserving the back-end of line (BEOL) structure, enabling spatial separation of the sensing area and electronics. The BOX etch critically affects sensor performance, as waveguide surface roughness can alter MRR properties and coupling. We analyzed MRR design variations, comparing wet and dry etching techniques for their effects on optical performance across rib and strip waveguides in quasi-TE and quasi-TM modes. Wafer-level measurements show that backside-released MRR achieve high extinction ratios with slightly reduced quality factors, advancing high-sensitivity photonic sensors.
T2 - SPIE Optics + Optoelectronics 2025
CY - Prague, Czech Republic
DA - 23.05.2025
KW - Photonic sensors
KW - Micro-ring resonator (MRR)
KW - Silicon on insulator (SOI)
KW - CMOS
KW - Local backside etching
PY - 2025
SN - 978-1-5106-8851-3
DO - https://doi.org/10.1117/12.3056481
VL - 13527
SP - 1
EP - 8
PB - SPIE
CY - Bellingham, WA , USA
AN - OPUS4-63585
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Steglich, Patrick
A1 - Paul, Martin
A1 - Fünning, Tabea
A1 - Schumann, Christoph
A1 - Mai, Christian
A1 - Tannenberg, Robert
A1 - Mai, Andreas
ED - Cheben, Pavel
ED - Čtyroký, Jiří
ED - Molina-Fernández, Iñigo
T1 - Towards monolithic integration of polymer-based electro-optical devices in silicon photonic integrated circuits using a 250nm SOI technology
N2 - Photonic micro-ring resonators (MRR) are widely studied for their high sensitivity across applications like environmental monitoring, healthcare, and chemical analysis. Their evanescent field sensing requires partially unembedded waveguides compatible with CMOS processing. Our approach uses local backside etching with an additional buried oxide (BOX) etch to release waveguides while preserving the back-end of line (BEOL) structure, enabling spatial separation of the sensing area and electronics. The BOX etch critically affects sensor performance, as waveguide surface roughness can alter MRR properties and coupling. We analyzed MRR design variations, comparing wet and dry etching techniques for their effects on optical performance across rib and strip waveguides in quasi-TE and quasi-TM modes. Wafer-level measurements show that backside-released MRR achieve high extinction ratios with slightly reduced quality factors, advancing high-sensitivity photonic sensors.
T2 - SPIE Optics + Optoelectronics 2025
CY - Prague, Czech Republic
DA - 05.06.2025
KW - Photonic sensors
KW - Micro-ring resonator (MRR)
KW - Silicon on insulator (SOI)
KW - CMOS
KW - Local backside etching (LBE)
PY - 2025
DO - https://doi.org/10.1117/12.3056280
VL - 13530
SP - 1
EP - 8
PB - SPIE
CY - Bellingham, WA , USA
AN - OPUS4-63587
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Cakir, Cafer Tufan
T1 - Algorithm-Assisted Multimodal Synchrotron Experiments: XRD–XES Integration and SpecTwin
N2 - Multimodal synchrotron-based techniques are emerging as powerful tools for advanced materials characterization, enabling simultaneous insights into both crystal and electronic structure. We present a combined X-ray diffraction (XRD) and high-resolution X-ray emission spectroscopy (XES) approach implemented in a double-dispersive setup. This configuration enables simultaneous acquisition of structural and spectroscopic information with high precision, allowing us to resolve correlations between lattice arrangements and electronic configurations under in situ conditions.
To enhance experimental throughput and reproducibility, we employ digital twin concepts and optimization algorithms for experiment design and parameter control. These methods effectively eliminate trial-and-error procedures when optimizing the setup to achieve the desired resolution for XES analysis. In addition, we introduce SpecTwin, a dedicated software environment that integrates XES data analysis, simulation, and optimization routines.
This combined methodology underscores the potential of algorithm-assisted multimodal X-ray experiments to advance the quantitative understanding of structure–property relationships in complex materials.
T2 - Joint BAM-HZB Symposium on Multimodal Synchrotron Experiments for Next-Generation Materials Research
CY - Berlin, Germany
DA - 25.02.2026
KW - XAS
KW - Digital Twin
KW - Optimization
KW - Multimodal
PY - 2026
AN - OPUS4-65608
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Schumann, Christoph
T1 - Design and optimization of integrated multimode interferometers (MMIs) for dual-polarization photonic biosensors for biomedical applications in a silicon-on-insulator platform
N2 - Faster, more sensitive, and cost-efficient diagnostic tests are crucial, as conventional lab tests are slow and expensive, while rapid tests often lack specificity. Advancements in medical diagnostics are crucial for early disease detection, reducing costs and testing time. Optical biosensors, particularly multimode interferometers (MMIs), offer high sensitivity and integration potential for Point-of-Care applications [1-2]. This work introduces a novel MMI biosensor utilizing orthogonal TE and TM modes, significantly minimizing the footprint.
T2 - SPIE Optics + Optoelectronics 2025
CY - Prague, Czech Republic
DA - 23.05.2025
KW - Interferometry
KW - Semiconductor
KW - Chip
KW - Point-of-Care applications
KW - Biomarker
PY - 2025
UR - https://www.spiedigitallibrary.org/conference-proceedings-of-spie/PC13527/PC135270R/Design-and-optimization-of-integrated-multimode-interferometers-MMIs-for-dual/10.1117/12.3056490.short
DO - https://doi.org/10.1117/12.3056490
AN - OPUS4-63568
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Döring, Sarah
T1 - Surface Immobilization of Recombinant Trypsin onto Corundum Particles for Optimized Antibody Digestion
N2 - Therapeutic monoclonal antibodies are the fastest-growing class of biological agents and the development of reliable analytical methods for their quantification is becoming increasingly important. Liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) represents one of the leading technologies for antibody quantification. The serin protease trypsin has emerged as the gold standard enzyme for digesting intact protein into peptides for this approach. However, many protocols exist that often lead to different results depending on the digestion procedure. In particular, the type and amounts of detergents added during sample preparation for protein unfolding before digestion is known to create undesirable structure modifications of proteins (e.g. carbamylation) and significant bias in measurement results by inhibiting enzyme activity. The source and nature of the enzyme itself can also have an influence, whereby immobilized variants are increasingly being used to improve their stability, minimize self-digestion and enable a higher substrate-enzyme ratio.
Here, we explored the potential of a novel thermostable trypsin and surface-functionalised corundum particles for enhanced antibody digestion. For this purpose, the inactive zymogen was recombinantly produced in E. coli, activated with enterokinase digestion and finally affinity purified by benzamidine purification. The enzyme activity was analogous to commercially available MS-grade trypsin product. In addition, produced trypsin showed increased thermal stability under typical digestion conditions compared to reference product. Furthermore, APTES-silanization followed by glutaraldehyde modification of corundum surface with an additional blocking step prevents nonspecific protein adsorption during the protein digestion procedure and the immobilized enzyme still showed substrate activity after covalent binding. Compared to wild-type and a non-immobilized enzyme, the surface-functionalized thermostable variant showed increased activity at elevated temperatures. Thus, this novel type of trypsin particles promises to not only improve antibody digestion at high temperatures, but also to prevent self-digestion and enable the separation of trypsin from target peptides in LC–MS analysis.
T2 - ANAKON 2025
CY - Leipzig, Germany
DA - 10.03.2025
KW - Antibody Quantification
KW - Corundum
KW - Enzyme Immobilization
KW - LC-MS/MS
PY - 2025
AN - OPUS4-63480
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Tannenberg, Robert
T1 - Troponin I Assay in Wafer-Level Backside Optofluidics
N2 - Cardiovascular diseases are the number one cause of death worldwide and responsible for 17.9 million casualities worldwide in 2019. Cardiac Troponin I (cTnI) is the most important biomarker for acute events such as heart attacks. The development of novel photonic integrated microchips (PIC) is a promising approach to allow the convenient detection of key biomarkers in complex matrices through multichannel real-time analysis in a highly compact package. This study presents the development and proof-of-concept of a backside released CMOS chip designed for the multichannel real-time detection of biomarkers. In this work, we introduce a Troponin I assay as well that utilizes a potential and practical approach to backside optofluidics on a wafer-level platform.
T2 - Biosensors 2025 - 35th Anniversary World Congress on Biosensors
CY - Lisbon, Portugal
DA - 19.05.2025
KW - Ring resonator
KW - Semiconductor
KW - CMOS
KW - cTnI
KW - Heart attack
KW - Biomarker
KW - Sandwich immunoassay
PY - 2025
AN - OPUS4-63481
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Tannenberg, Robert
T1 - Multichannel real-time detection of biomarkers with highly miniaturized photonic microchips
N2 - The development of novel photonic microchips is a promising approach to advance the detection of biomarkers through multichannel real-time analysis. This study reports the successful development of a backside released CMOS chip designed for the multichannel real-time detection of biomarkers. Operating at a wavelength of 1550 nm, the microchip features three detection channels in addition to a reference channel, enabling simultaneous analysis of multiple biomarkers.
The microchip incorporates micro-ring resonators that are directly functionalized with specific bioreceptors, which significantly improves the affinity towards target biomarkers. The employed surface functionalization strategy enables versatile immobilization of receptor molecules and serves as a starting point for various analytical applications.
A tunable laser is utilized as the excitation source, providing precise wavelength tuning and stable optical output, essential for achieving optimal resonance conditions within the micro-ring resonators. Our chips use integrated multi-mode interferometers as beam-splitter, grating coupler and Ge-photodiodes, resulting in an ultra-small footprint. The complete chip including metal pads has an area of 1 mm2.
The results indicate that the developed multichannel photonic microchip system enables online detection of multiple biomarkers. The compact and highly miniaturized design of this microchip positions them as promising candidates for point-of-care diagnostics and personalized medicine applications. With further advancements, this technology opens a path to transform biomarker detection across various medical fields, offering rapid, reliable, and cost-effective diagnostic solutions. In conclusion, the presented multichannel photonic microchips signify a substantial leap forward in real-time biomarker detection, providing a robust platform for future research and clinical applications.
T2 - SPIE Optics + Optoelectronics 2025
CY - Prague, Czech Republic
DA - 07.04.2025
KW - Biosensor
KW - Optics
KW - Silicon semiconductor
KW - Proteins
KW - Clinical chemistry
PY - 2025
AN - OPUS4-62954
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Döring, Sarah
T1 - Optimization of Polymer Interface: Novel Surface-functionalized Corundum Particles for Improved Antibody Digestion
N2 - Therapeutic monoclonal antibodies are the fastest-growing class of biological agents and the development of reliable analytical methods for their quantification is becoming increasingly important. Liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) represents one of the leading technologies for antibody quantification. The serin protease trypsin has emerged as the gold standard enzyme for digesting intact protein into peptides for this approach. However, many protocols exist that often lead to different results. The talk will provide a brief introduction to the application of novel thermostable and surface-functionalized trypsin particles for improved antibody digestion as well as initial successes in polymer functionalization of the corundum surface to prevent nonspecific protein adsorption during the digestion procedure.
T2 - SALSA Make and Measure 2024: Interfaces
CY - Berlin, Germany
DA - 11.09.2024
KW - Antibody Quantification
KW - Recombinant Enzymes
KW - LC-MS/MS
KW - Enzyme Immobilisation
KW - Surface Functionalisation
KW - Corundum
PY - 2024
AN - OPUS4-61041
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Döring, Sarah
T1 - Sequence of Mus Musculus monoclonal IgG2c anti-CCMV Immunoglobulin
N2 - We report the full-length nucleotide and amino acid sequences of the light (κ) and heavy chain of the IgG2c anti-CCMV monoclonal antibody (hybridoma clone BAM-CCMV-29-81), generated against Cowpea Chlorotic Mottle Virus (CCMV). Sequencing of hybridoma clone was performed using a cost-effective Sanger-based workflow that includes DNA-level subclass determination and peptide mass fingerprint confirmation. The κ-chain sequence was assigned to IGKV4-6101 / IGKJ101, while the heavy chain was assigned to IGHV2-601 / IGHD1-101 / IGHJ3*01 with IgG2c constant regions from the NOD strain. Both chains were validated against RNA Illumina sequencing, confirming 100% identity. The sequences are available in GenBank under accession numbers PX123807 (κ-chain) and PX123808 (heavy chain).
KW - Antibody Sequencing
KW - BAM-CCMV-29-81
KW - anti-CCMV-antibody
PY - 2025
UR - https://www.ncbi.nlm.nih.gov/nuccore/PX123807
UR - https://www.ncbi.nlm.nih.gov/nuccore/PX123808
PB - National Library of Medicine
CY - Bethesda
AN - OPUS4-63968
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - INPR
A1 - Fischer, Janina
A1 - Kaufmann, Jan Ole
A1 - Weller, Michael G.
T1 - Simple Determination of Affinity Constants of Antibodies by Competitive Immunoassays
N2 - The affinity constant, also known as the equilibrium constant, binding constant, equilibrium association constant, or the reciprocal value, the equilibrium dissociation constant (Kd), can be considered as one of the most important characteristics for any antibody-antigen pair. Many methods based on different technologies have been proposed and used to determine this value. However, since a very large number of publications and commercial datasheets do not include this nformation, significant obstacles in performing such measurements seem to exist. In other cases where such data are reported, the results have often proved to be unreliable. This situation may indicate that most of the technologies available today require a high level of expertise that does not seem to be available in many laboratories. In this paper, we present a simple approach based on standard immunoassay technology that is easy and quick to perform. It relies on the effect that the molar IC50 approaches the Kd value in the case of infinitely small concentrations of the reagent concentrations. A two-dimensional dilution of the reagents leads to an asymptotic convergence to Kd. The approach has some similarity to the well-known checkerboard titration used for the optimization of immunoassays. A well-known antibody against the FLAG peptide, clone M2, was used as a model system and the results were compared with other methods. This approach could be used in any case where a competitive assay is available or can be developed. The determination of an affinity constant should belong to the crucial parameters in any quality control of antibody-related products and assays and should be mandatory in papers using immunochemical protocols.
N2 - Die Affinitätskonstante, auch bekannt als Gleichgewichtskonstante, Bindungskonstante, Gleichgewichtsassoziationskonstante oder der Kehrwert, die Gleichgewichtsdissoziationskonstante (Kd), kann als eine der wichtigsten Eigenschaften für jedes Antikörper-Antigen-Paar angesehen werden. Es wurden viele Methoden auf der Grundlage verschiedener Technologien vorgeschlagen und verwendet, um diesen Wert zu bestimmen. Da jedoch eine sehr große Anzahl von Veröffentlichungen und kommerziellen Datenblättern diese Informationen nicht enthalten, scheint es erhebliche Hindernisse bei der Durchführung solcher Messungen zu geben. In anderen Fällen, in denen solche Daten angegeben werden, haben sich die Ergebnisse oft als unzuverlässig erwiesen. Diese Situation könnte darauf hindeuten, dass die meisten der heute verfügbaren Technologien ein hohes Maß an Fachwissen erfordern, das in vielen Laboren nicht vorhanden zu sein scheint. In diesem Artikel stellen wir einen einfachen Ansatz vor, der auf der Standard-Immunoassay-Technologie basiert und einfach und schnell durchzuführen ist. Er beruht auf dem Effekt, dass sich der molare IC50-Wert dem Kd-Wert im Fall unendlich kleiner Konzentrationen der Reagenzienkonzentrationen nähert. Eine zweidimensionale Verdünnung der Reagenzien führt zu einer asymptotischen Konvergenz zu Kd. Der Ansatz weist eine gewisse Ähnlichkeit mit der bekannten Schachbrett-Titration auf, die zur Optimierung von Immunoassays verwendet wird. Ein bekannter Antikörper gegen das FLAG-Peptid, Klon M2, wurde als Modellsystem verwendet und die Ergebnisse wurden mit anderen Methoden verglichen. Dieser Ansatz kann in allen Fällen verwendet werden, in denen ein kompetitiver Test verfügbar ist oder entwickelt werden kann. Die Bestimmung einer Affinitätskonstante sollte zu den entscheidenden Parametern in jeder Qualitätskontrolle von Antikörper-bezogenen Produkten und Tests gehören und in Veröffentlichungen, die immunchemische Protokolle verwenden, obligatorisch sein.
KW - ELISA
KW - Microplate
KW - Microtiter plate
KW - IC50
KW - Test midpoint
KW - Competitive immunoassay
KW - Law of mass action
KW - Thermodynamics
KW - Equilibrium constant
KW - SPR
KW - Surface plasmon resonance
KW - Clones
KW - Interaction
KW - kd value
KW - ITC
KW - MST
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-621298
DO - https://doi.org/10.20944/preprints202404.0996.v1
SN - 2310-287X
SP - 1
EP - 11
PB - MDPI
CY - Basel
AN - OPUS4-62129
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bartczak, Dorota
A1 - Sikora, Aneta
A1 - Goenaga-Infante, Heidi
A1 - Altmann, Korinna
A1 - Drexel, Roland
A1 - Meier, Florian
A1 - Alasonati, Enrica
A1 - Lelong, Marc
A1 - Cado, Florence
A1 - Chivas-Joly, Carine
A1 - Fadda, Marta
A1 - Sacco, Alessio
A1 - Rossi, Andrea Mario
A1 - Pröfrock, Daniel
A1 - Wippermann, Dominik
A1 - Barbero, Francesco
A1 - Fenoglio, Ivana
A1 - Booth, Andy M.
A1 - Sørensen, Lisbet
A1 - Igartua, Amaia
A1 - Wouters, Charlotte
A1 - Mast, Jan
A1 - Barbaresi, Marta
A1 - Rossi, Francesca
A1 - Piergiovanni, Maurizio
A1 - Mattarozzi, Monica
A1 - Careri, Maria
A1 - Caebergs, Thierry
A1 - Piette, Anne-Sophie
A1 - Parot, Jeremie
A1 - Giovannozzi, Andrea Mario
T1 - Multiparameter characterisation of a nano-polypropylene representative test material with fractionation, light scattering, high-resolution microscopy, spectroscopy, and spectrometry methods
N2 - Reference and quality control materials with comparable physicochemical properties to nanoplastic contaminants present in environmental and food nanoplastics are currently lacking. Here we report a nanoplastic polypropylene material prepared using a top-down approach involving mechanical fragmentation of larger plastics. The material was found to be homogeneous and stable in suspension and has been characterised for average particle size, size distribution range, particle number concentration, polypropylene mass fraction and inorganic impurity Content using a wide range of analytical methods, including AF4, cFFF, PTA, (MA)DLS, MALS, SEM, AFM, TEM, STEM, EDS,Raman, ICP-MS and pyGC-MS. The material was found to have a broad size distribution, ranging from 50 nm to over 200 nm, with the average particle size value dependent on the technique used to determine it. Particle number concentration ranged from 1.7–2.4 × 1010 g−1 , according to PTA. Spectroscopy techniques confirmed that the material was polypropylene, with evidence of aging due to an increased level of oxidation. The measured mass fraction was found to depend on the marker used and ranged between 3 and 5 μg g−1 . Inorganic impurities such as Si, Al, Mg, K, Na, S, Fe, Cl and Ca were also identified at ng g−1 levels. Comparability and complementarity across the measurement methods and techniques is also discussed.
KW - Polypropylene
KW - Nanoplastics
KW - Analytics
KW - Reference material
KW - Scattering methods
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654680
DO - https://doi.org/10.1039/D5EN00917K
SN - 2051-8153
SP - 1
EP - 15
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-65468
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bach, S.
A1 - Visnow, E.
A1 - Panthöfer, M.
A1 - Gorelik, T.
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Gulo, A.
A1 - Kolb, U.
A1 - Emmerling, Franziska
A1 - Lind, C.
A1 - Tremel, W.
T1 - Hydrate networks under mechanical stress – A case study for Co3(PO4)2·8H2O
N2 - The nature of the bound water in solids with hydrogen-bonded networks depends not only on temperature and pressure but also on the nature of the constituents. The collapse and reorientation of these network structures determines the stability of hydrated solids and transitions to other crystalline or amorphous phases. Here, we study the mechanochemically induced loss of bound water in Co₃(PO₄)₂·8H₂O and compare this process to the behavior under hydrostatic pressure.
The associated phase transition and its kinetics were monitored by X-ray powder diffraction with Synchrotron radiation and quantitative IR spectroscopy. High shearing forces are responsible for the degradation of the hydrogen-bonded network and the concomitant crystalline–amorphous transformation. UV/Vis spectroscopy, extended X-ray absorption spectroscopy (EXAFS), and X-ray absorption near-edge spectroscopy (XANES) provided information about the short-range order in the amorphous solid, and thermal analysis revealed its composition and showed that the moderate charge densities of the Co²⁺ and PO₄³⁻ ions, which make the hydration enthalpy comparable to the binding energy of the counteranions, and the Formation of hydrogen-bonded networks favor multistage crystallization processes associated with the release and uptake of coordinated water. The changes of the Co²⁺ coordination induce a color change from pink to blue; therefore, Co₃(PO₄)₂·8H₂O can be used as an overheat temperature indicator.
KW - Mechanochemistry
KW - Amorphous materials
KW - Hydrates
KW - Cobalt
KW - Phosphates
PY - 2016
DO - https://doi.org/10.1002/ejic.201501481
SN - 1434-1948
SN - 1099-0682
VL - 2016
IS - 13-14
SP - 2072
EP - 2081
PB - Wiley-VCH Verlag GmbH & Co. KGaA
CY - Weinheim, Germany
AN - OPUS4-36434
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Cakir, Cafer Tufan
T1 - Bayesian optimization for depth resolved analysis of complex alloys with grazing exit XANES
N2 - Compositionally complex alloys (CCAs) are a new class of alloys containing at least 5 elements with concentrations between 5 and 35 atomic percent. Due to their adjustable composition, which enables modifications of mechanical properties (such as hardness, strength and ductility etc) and their stability at high temperatures, CCAs have been the focus of various studies [1,2]. Especially the corrosion behavior of CCAs has been a wide research interest.
However, there are only few studies that deals with the degradation process on such materials, which is highly relevant for the safety aspect for future component design. To thoroughly investigate the corrosion processes and to determine oxidation states of metal components within the reaction products, we need special analytical tools. Since the grazing exit X-ray fluorescence (GEXRF) offers a non-destructive way to collect notable information regarding the high temperature oxidation, we consider it as a useful method to investigate how CCAs behave in corrosive environments.
The main idea of grazing geometry is to enhance the fluorescence signal of the surface. This enables highly sensitive surface analyses of thin protective film on surface in sub-micrometer scale [3]. When compared to a conventional CCD-based camera, the advantage and most important feature of the detector system (Color X-Ray Camera (CXC)) is that each pixel is an energy sensitive detector. The position and area sensitive detector, with 264x264 pixel detector area, provides information regarding the signal emitted from the sample as a function of the emission angle and thus allows depth-sensitive analysis. Furthermore, the data collected from samples of an incidence energy which can be controlled with a resolution of 0.5 eV provides XANES data to determine oxidation states.
In this contribution, we address the feasibility of our setup and new optimization procedure (Bayesian Optimization and Gaussian Regression). The results of a conceptual study regarding layer properties of the reference sample (Cr-Oxide layer (300nm) on Cr layer (500nm) on Si wafer) and CrCoNi (Cr-Oxide (>1µm) layer on CrCoNi substrate) medium entropy alloy.
T2 - European Conference on X-ray Spectrometry. EXRS 2022
CY - Bruges, Belgium
DA - 26.06.2022
KW - GEXRF
KW - High entropy alloys
KW - XANES
KW - Grazing exit
KW - High entropy materials
KW - XAS
KW - Optimization
PY - 2022
AN - OPUS4-56272
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - In situ characterization of nucleation, growth, crystallization and dissolution of nanoscaled iron oxides
N2 - Nucleation and growths of iorn oxide nanoparticles studied in situ using XRD, XRF, SAXS and XANES.
T2 - International CRC meeting
CY - Berlin, Germany
DA - 10.10.2018
KW - XRD
KW - XANES
PY - 2018
AN - OPUS4-46995
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - THES
A1 - Abbas, Ioana M.
T1 - Development of LC-MS/MS methods for the quantitative determination of hepcidin-25, a key regulator of iron metabolism
N2 - Isotope-dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) is emerging in the field of clinical chemistry and laboratory medicine as an alternative to immunoassays and is acknowledged as the MS “gold standard” for small biomolecule quantification. Hepcidin-25, a key iron-regulatory peptide hormone discovered in 2000, has revolutionized the understanding of iron disorders and its quantitative determination in biological samples should advance the management of iron-related pathology (diagnosis, prognosis and treatment). This study applied LC-MS/MS, using the triple quadrupole (QqQ) mass spectrometer, in a rapid and robust analytical strategy for the quantification of hepcidin-25 in human serum, to be implemented in routine laboratories. For this purpose, two sample preparation strategies and two complementary chromatographic separation conditions were investigated, where the use of acidic mobile phases (0.1% trifluoroacetic acid) was compared with a novel approach involving solvents at high pH (containing 0.1% ammonia). The application of these LC-MS/MS methods to human samples in an intra-laboratory comparison, using the same hepcidin-25 calibrators, yielded a very good correlation of the results. The LC-MS/MS employing trifluoroacetic acid-based mobile phases was selected as a highly sensitive (limit of quantification LOQ of 0.5 μg/L) and precise (coefficient of variation CV<15%) method and was recommended as a reference method candidate for hepcidin-25 quantification in real samples (in the dynamic range of 0.5-40 μg/L). One of the novel aspects of the methodology was the use of amino- and fluoro-silanized autosampler vials to reduce the interaction of the 25-residue peptide to laboratory glassware surfaces. Moreover, this LC-MS/MS method was used for an international round robin study, applying a secondary reference material as a calibrator. By determining the degree of equivalence between the results of the ten participating methodologies, the performance of the method developed in this study was found to be in the optimal range as defined by the International Consortium for Harmonization of Clinical Laboratory Results (ICHCLR). In this work, the formation of hepcidin-25 complexes with copper(II) was investigated. The first reversed-phase chromatographic separation of hepcidin-25/Cu2+ and hepcidin-25 (copper “free”) was achieved by applying mobile phases containing 0.1% of ammonia (pH 11). LC-MS/MS and high-resolution mass spectrometry (Fourier-transform ion cyclotron resonance (FTICR) MS) were applied for the mass spectrometric characterization of the formed hepcidin-25-Cu(II) species at pH values of 11 and 7.4 respectively. A new species corresponding to hepcidin-25 complexed with two copper ions was identified at high pH.
KW - Copper
KW - LC-MS/MS
KW - Chromatography
KW - Mass spectrometry
KW - Metal complex
KW - Metalloprotein
KW - Peptide
KW - Metrology
KW - Reference material
PY - 2018
UR - https://nbn-resolving.org/urn:nbn:de:kobv:11-110-18452/20119-6
UR - https://edoc.hu-berlin.de/handle/18452/20119?show=full
DO - https://doi.org/10.18452/19358
SP - 1
EP - 156
CY - Berlin
AN - OPUS4-45780
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Steglich, P.
A1 - Rabus, D. G.
A1 - Sada, C.
A1 - Paul, Martin
A1 - Weller, Michael G.
A1 - Mai, C.
A1 - Mai, A.
T1 - Silicon Photonic Micro-Ring Resonators for Chemical and Biological Sensing: A Tutorial
N2 - Silicon photonic micro-ring resonators (MRR) developed on the silicon-on-insulator (SOI) platform, owing to their high sensitivity and small footprint, show great potential for many chemical and biological sensing applications such as label-free detection in environmental monitoring, biomedical engineering, and food analysis. In this tutorial, we provide the theoretical background and give design guidelines for SOI-based MRR as well as examples of surface functionalization procedures for label-free detection of molecules.
After introducing the advantages and perspectives of MRR, fundamentals of MRR are described in detail, followed by an introduction to the fabrication methods, which are based on a complementary metal-oxide semiconductor (CMOS) technology. Optimization of MRR for chemical and biological sensing is provided, with special emphasis on the optimization of waveguide geometry. At this point, the difference between chemical bulk sensing and label-free surface sensing is explained, and definitions like waveguide sensitivity, ring sensitivity, overall sensitivity as well as the limit of detection (LoD) of MRR are introduced. Further, we show and explain chemical bulk sensing of sodium chloride (NaCl) in water and provide a recipe for label-free surface sensing.
KW - Lab on a chip
KW - Biosensor
KW - Cmos
KW - Silanization
KW - Surface derivatization
KW - Evanescent wave
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-529360
DO - https://doi.org/10.36227/techrxiv.14909901.v1
SP - 1
EP - 18
PB - IEEE
CY - Piscataway Township
AN - OPUS4-52936
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Paul, Martin
A1 - Tannenberg, Robert
A1 - Tscheuschner, Georg
A1 - Ponader, Marco
A1 - Weller, Michael G.
T1 - Cocaine detection by a laser-induced immunofluorometric biosensor
N2 - The trafficking of illegal drugs by criminal networks at borders, harbors, or airports is an increasing issue for public health as these routes ensure the main supply of illegal drugs. The prevention of drug smuggling, including the installation of scanners and other analytical devices to detect small traces of drugs within a reasonable time frame, remains a challenge. The presented immunosensor is based on a monolithic affinity column with a large excess of immobilized hapten, which traps fluorescently labeled antibodies as long as the analyte cocaine is absent. In the presence of the drug, some binding sites of the antibody will be blocked, which leads to an immediate breakthrough of the labeled protein, detectable by highly sensitive laser-induced fluorescence with the help of a Peltier-cooled complementary metal-oxide-semiconductor (CMOS) camera. Liquid handling is performed with high-precision syringe pumps and microfluidic chip-based mixing devices and flow cells. The biosensor achieved limits of detection of 7 ppt (23 pM) of cocaine with a response time of 90 s and a total assay time below 3 min. With surface wipe sampling, the biosensor was able to detect 300 pg of cocaine. This immunosensor belongs to the most sensitive and fastest detectors for cocaine and offers near-continuous analyte measurement.
KW - Online detection
KW - Security
KW - Monoclonal antibody
KW - Microfluidic mixing
KW - Microfluidics
KW - Lab-on-a-chip
KW - Monolithic column
KW - Affinity chromatography
KW - Laser-induced fluorescence
KW - LIF
KW - ELISA
KW - Wipe test
KW - Low-cost
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-534487
DO - https://doi.org/10.3390/bios11090313
VL - 11
IS - 9
SP - 1
EP - 15
PB - MDPI
CY - Basel
AN - OPUS4-53448
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Möckel, J.
A1 - Brangsch, J.
A1 - Reimann, C.
A1 - Kaufmann, Jan Ole
A1 - Sack, I.
A1 - Mangarova, D. B.
A1 - Kader, A.
A1 - Taupitz, M.
A1 - Adams, L. C.
A1 - Keller, S.
A1 - Ludwig, A.
A1 - Hamm, B.
A1 - Botnar, R. M.
A1 - Makowski, M. R.
T1 - Assessment of Albumin ECM Accumulation and Inflammation as Novel In Vivo Diagnostic Targets for Multi-Target MR Imaging
N2 - Atherosclerosis is a progressive inflammatory vascular disease characterized by endothelial dysfunction and plaque burden. Extracellular matrix (ECM)-associated plasma proteins play an important role in disease development. Our magnetic resonance imaging (MRI) study investigates the feasibility of using two different molecular MRI probes for the simultaneous assessment of ECM-associated intraplaque albumin deposits caused by endothelial damage and progressive inflammation in atherosclerosis. Male apolipoprotein E-deficient (ApoE-/-)-mice were fed a high-fat diet (HFD) for 2 or 4 months. Another ApoE-/--group was treated with pravastatin and received a HFD for 4 months. T1- and T2*-weighted MRI was performed before and after albumin-specific MRI probe (gadofosveset) administration and a macrophage-specific contrast agent (ferumoxytol). Thereafter, laser ablation inductively coupled plasma mass spectrometry and histology were performed. With advancing atherosclerosis, albumin-based MRI signal enhancement and ferumoxytol-induced signal loss areas in T2*-weighted MRI increased. Significant correlations between contrast-to-noise-ratio (CNR) post-gadofosveset and albumin stain (R2 = 0.78, p < 0.05), and signal loss areas in T2*-weighted MRI with Perls’ Prussian blue stain (R2 = 0.83, p < 0.05) were observed. No interference of ferumoxytol with gadofosveset enhancement was detectable. Pravastatin led to decreased inflammation and intraplaque albumin. Multi-target MRI combining ferumoxytol and gadofosveset is a promising method to improve diagnosis and treatment monitoring in atherosclerosis.
KW - Magnetic resonance imaging
KW - MRI
KW - Imaging
KW - Human serum albumin
KW - Extracellular matrix
KW - Macrophages
KW - Contrast agent
KW - Atherosclerotic plaques
KW - Gadofosveset
KW - Aneurysm
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-536725
DO - https://doi.org/10.3390/biology10100964
VL - 10
IS - 10
SP - 1
EP - 16
PB - MDPI
CY - Basel
AN - OPUS4-53672
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Backes, A. T.
A1 - Reinmuth-Selzle, K.
A1 - Leifke, A. L.
A1 - Ziegler, K.
A1 - Krevert, C. S.
A1 - Tscheuschner, Georg
A1 - Lucas, K.
A1 - Weller, Michael G.
A1 - Berkemeier, T.
A1 - Pöschl, U.
A1 - Fröhlich-Nowoisky, J.
T1 - Oligomerization and Nitration of the Grass Pollen Allergen Phl p 5 by Ozone, Nitrogen Dioxide, and Peroxynitrite: Reaction Products, Kinetics, and Health Effects
N2 - The allergenic and inflammatory potential of proteins can be enhanced by chemical modification upon exposure to atmospheric or physiological oxidants. The molecular mechanisms and kinetics of such modifications, however, have not yet been fully resolved. We investigated the oligomerization and nitration of the grass pollen allergen Phl p 5 by ozone (O3), nitrogen dioxide (NO2), and peroxynitrite (ONOO–). Within several hours of exposure to atmospherically relevant concentration levels of O3 and NO2, up to 50% of Phl p 5 were converted into protein oligomers, likely by formation of dityrosine cross-links. Assuming that tyrosine residues are the preferential site of nitration, up to 10% of the 12 tyrosine residues per protein monomer were nitrated. For the reaction with peroxynitrite, the largest oligomer mass fractions (up to 50%) were found for equimolar concentrations of peroxynitrite over tyrosine residues. With excess peroxynitrite, the nitration degrees increased up to 40% whereas the oligomer mass fractions decreased to 20%. Our results suggest that protein oligomerization and nitration are competing processes, which is consistent with a two-step mechanism involving a reactive oxygen intermediate (ROI), as observed for other proteins. The modified proteins can promote pro-inflammatory cellular signaling that may contribute to chronic inflammation and allergies in response to air pollution.
KW - Protein
KW - Nitrotyrosine
KW - Dityrosine
KW - Allergy
KW - Hay fever
KW - Diesel exhaust
KW - Combustion
KW - Exhaust
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-529729
DO - https://doi.org/10.3390/ijms22147616
VL - 22
IS - 14
PB - MDPI
CY - Basel
AN - OPUS4-52972
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Adams, L. C.
A1 - Brangsch, J.
A1 - Reimann, C.
A1 - Kaufmann, Jan Ole
A1 - Buchholz, R.
A1 - Karst, U.
A1 - Botnar, R. M.
A1 - Hamm, B.
A1 - Makowski, M. R.
T1 - Simultaneous molecular MRI of extracellular matrix collagen and inflammatory activity to predict abdominal aortic aneurysm rupture
N2 - Abdominal aortic aneurysm (AAA) is a life-threatening vascular disease with an up to 80% mortality in case of rupture. Current biomarkers fail to account for size-independent risk of rupture. By combining the information of different molecular probes, multi-target molecular MRI holds the potential to enable individual characterization of AAA. In this experimental study, we aimed to examine the feasibility of simultaneous imaging of extracellular collagen and inflammation for size-independent prediction of risk of rupture in murine AAA. The study design consisted of: (1) A outcome-based longitudinal study with imaging performed once after one week with follow-up and death as the end-point for assessment of rupture risk. (2) A week-by-week study for the characterization of AAA development with imaging after 1, 2, 3 and 4 weeks. For both studies, the animals were administered a type 1 collagen-targeted gadolinium-based probe (surrogate marker for extracellular matrix (ECM) remodeling) and an iron oxide-based probe (surrogate marker for inflammatory activity), in one imaging session. In vivo measurements of collagen and iron oxide probes showed a significant correlation with ex vivo histology (p < 0.001) and also corresponded well to inductively-coupled plasma-mass spectrometry and laser-ablation inductively-coupled plasma mass spectrometry. Combined evaluation of collagen-related ECM remodeling and inflammatory activity was the most accurate predictor for AAA rupture (sensitivity 80%, specificity 100%, area under the curve 0.85), being superior to information from the individual probes alone. Our study supports the feasibility of a simultaneous assessment of collagen-related extracellular matrix remodeling and inflammatory activity in a murine model of AAA.
KW - Atherosclerosis
KW - Specific probe
KW - Magnetic resonance imaging
KW - Gadolinium
KW - Iron oxide
KW - Ferumoxytol
KW - Inductively‑coupled mass spectrometry
KW - ICP-MS
KW - LA-ICP-MS
KW - Laser ablation
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-525864
UR - https://www.nature.com/articles/s41598-020-71817-x
DO - https://doi.org/10.1038/s41598-020-71817-x
VL - 10
IS - 1
SP - 15206
PB - Springer Nature Limited
CY - London, New York, Berlin, Shanghai and Tokyo
AN - OPUS4-52586
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - INPR
A1 - Paul, Martin
A1 - Tannenberg, Robert
A1 - Tscheuschner, Georg
A1 - Ponader, Marco
A1 - Weller, Michael G.
T1 - Cocaine detection by a laser-induced immunofluorometric biosensor
N2 - The trafficking of illegal drugs by criminal networks at borders, harbors, or airports is an increasing issue in public health as these routes ensure the main supply of illegal drugs. The prevention of drug smuggling, including the installation of scanners and other analytical devices to detect ultra-small traces of drugs within a reasonable time frame, remains a challenge. The presented immunosensor is based on a monolithic affinity column with a large excess of immobilized hapten, which traps fluorescently labeled antibodies as long as the analyte cocaine is absent. In the presence of the drug, some binding sites of the antibody will be blocked, which leads to an immediate breakthrough of the labeled protein, detectable by highly sensitive laser-induced fluorescence with the help of a Peltier-cooled complementary metal-oxide-semiconductor (CMOS) camera. Liquid handling is performed with high-precision syringe pumps and microfluidic chip-based mixing devices and flow cells. The biosensor achieved limits of detection of 23 pM (7 ppt) of cocaine with a response time of 90 seconds and a total assay time below 3 minutes. With surface wipe sampling, the biosensor was able to detect 300 pg of cocaine. This immunosensor belongs to the most sensitive and fastest detectors for cocaine and offers near-continuous analyte measurement.
KW - Drug search
KW - Customs
KW - Confiscation
KW - Border surveillance
KW - Narcotics
KW - International drug trade
KW - Drug trafficking
KW - Illicit drug
KW - Immunosensor
KW - Antibodies
KW - Detection
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-529951
DO - https://doi.org/10.20944/preprints202107.0521.v1
SN - 2310-287X
N1 - Geburtsname von Ponader, Marco: Wilke, M. - Birth name of Ponader, Marco: Wilke, M.
SP - 1
PB - MDPI
CY - Basel
AN - OPUS4-52995
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ponader, Marco
A1 - Röder, Bettina
A1 - Paul, Martin
A1 - Weller, Michael G.
T1 - Sintered glass monoliths as supports for affinity columns
N2 - A novel stationary phase for affinity separations is presented. This material is based on sintered borosilicate glass readily available as semi-finished filter plates with defined porosity and surface area. The material shows fast binding kinetics and excellent long-term stability under real application conditions due to lacking macropores and high mechanical rigidity. The glass surface can be easily modified with standard organosilane chemistry to immobilize selective binders or other molecules used for biointeraction. In this paper, the manufacturing of the columns and their respective column holders by 3D printing is shown in detail. The model system protein A/IgG was chosen as an example to examine the properties of such monolithic columns under realistic application conditions. Several specifications, such as (dynamic) IgG capacity, pressure stability, long-term performance, productivity, non-specific binding, and peak shape, are presented. It could be shown that due to the very high separation speed, 250 mg antibody per hour and column can be collected, which surpasses the productivity of most standard columns of the same size. The total IgG capacity of the shown columns is around 4 mg (5.5 mg/mL), which is sufficient for most tasks in research laboratories. The cycle time of an IgG separation can be less than 1 min. Due to the glass material’s excellent pressure resistance, these columns are compatible with standard HPLC systems. This is usually not the case with standard affinity columns, limited to manual use or application in low-pressure systems. The use of a standard HPLC system also improves the ability for automation, which enables the purification of hundreds of cell supernatants in one day. The sharp peak shape of the elution leads to an enrichment effect, which might increase the concentration of IgG by a factor of 3. The final concentration of IgG can be around 7.5 mg/mL without the need for an additional nano-filtration step. The purity of the IgG was > 95% in one step and nearly 99% with a second polishing run.
KW - Affinity Chromatography
KW - Affinity Extraction
KW - Affinity Separation
KW - Protein Purification
KW - Down Stream Processing
KW - Antibody Purification
KW - Diagnostic Antibodies
KW - Therapeutic Antibodies
KW - Automated Purification
KW - HPLC
KW - FPLC
KW - IgG determination
KW - Concentration step
KW - Monoclonal Antibodies
KW - Polyclonal Antibodies
KW - Human Plasma
KW - Glass Support
KW - Borosilicate Glass
KW - Monolith
KW - Sintered Material
KW - Additive Manufacturing
KW - Column holder
KW - Construction
KW - Open Science
KW - Citizen Science
KW - Protein A
KW - Regeneration
KW - High-Speed Separations
KW - Robustness
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-527581
DO - https://doi.org/10.3390/separations8050056
SN - 2297-8739
N1 - Geburtsname von Ponader, Marco: Wilke, M. - Birth name of Ponader, Marco: Wilke, M.
VL - 8
IS - 5
SP - 1
EP - 16
PB - MDPI
CY - Basel
AN - OPUS4-52758
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Adams, L. C.
A1 - Brangsch, J.
A1 - Reimann, C.
A1 - Kaufmann, Jan Ole
A1 - Nowak, K.
A1 - Buchholz, R.
A1 - Karst, U.
A1 - Botnar, R. M.
A1 - Hamm, B.
A1 - Makowski, M. R.
T1 - Noninvasive imaging of vascular permeability to predict the risk of rupture in abdominal aortic aneurysms using an albumin binding probe
N2 - Abdominal aortic aneurysm (AAA) remains a fatal disease. Its development encompasses a complex interplay between hemodynamic stimuli on and changes in the arterial wall. Currently available biomarkers fail to predict the risk of AAA rupture independent of aneurysm size. Therefore, novel biomarkers for AAA characterization are needed. In this study, we used a mouse model of AAA to investigate the potential of magnetic resonance imaging (MRI) with an albumin-binding probe to assess changes in vascular permeability at different stages of aneurysm growth. Two imaging studies were performed: a longitudinal study with follow-up and death as endpoint to predict rupture risk and a week-by-week study to characterize AAA development. AAAs, which eventually ruptured, demonstrated a significantly higher in vivo MR signal enhancement from the albumin-binding probe (p = 0.047) and a smaller non-enhancing thrombus area compared to intact AAAs (p = 0.001). The ratio of albumin-binding-probe enhancement of the aneurysm wall to size of non-enhancing-thrombus-area predicted AAA rupture with high sensitivity/specificity (100%/86%). More advanced aneurysms with higher vascular permeability demonstrated an increased uptake of the albumin-binding-probe. These results indicate that MRI with an albumin-binding probe may enable noninvasive assessment of vascular permeability in murine AAAs and prediction of rupture risk.
KW - Magnetic resonance imaging
KW - Imaging
KW - Tomography
KW - Gadolinium
KW - Contrast agent
KW - Atherosclerosis
KW - ICP-MS
KW - Gadofosveset
KW - Angiography
KW - LA-ICP-MS
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-525541
DO - https://doi.org/10.1038/s41598-020-59842-2
VL - 10
SP - Article number: 3231
PB - Springer Nature Limited
CY - London, New York, Berlin, Shanghai and Tokyo
AN - OPUS4-52554
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - INPR
A1 - Ponader, Marco
A1 - Röder, Bettina
A1 - Paul, Martin
A1 - Weller, Michael G.
T1 - Sintered glass monoliths as new supports for affinity columns
N2 - A novel stationary phase for affinity separations is presented. This material is based on sintered borosilicate glass readily available as semi-finished filter plates with defined porosity and surface area. The material shows fast binding kinetics and excellent long-term stability under real application conditions due to lacking macropores and high mechanical rigidity. The glass surface can be easily modified with standard organosilane chemistry to immobilize selective binders or other molecules used for biointeraction. In this paper, the manufacturing of the columns and their respective column holders by 3D printing is shown in detail. The model system protein A/IgG was chosen as an example to examine the properties of such monolithic columns under realistic application conditions. Several specifications, such as (dynamic) IgG capacity, pressure stability, long-term performance, productivity, non-specific binding, and peak shape, are presented. It could be shown that due to the very high separation speed, 250 mg antibody per hour and column can be collected, which surpasses the productivity of most standard columns of the same size. The total IgG capacity of the shown columns is around 4 mg (5.5 mg/mL), which is sufficient for most tasks in research laboratories. The cycle time of an IgG separation can be less than 1 minute. Due to the glass material's excellent pressure resistance, these columns are compatible with standard HPLC systems. This is usually not the case with standard affinity columns, limited to manual use or application in low-pressure systems. The use of a standard HPLC system also improves the ability for automation, which enables the purification of hundreds of cell supernatants in one day. The sharp peak shape of the elution leads to an enrichment effect, which might increase the concentration of IgG by a factor of 3. The final concentration of IgG can be around 7.5 mg/mL without the need for an additional nanofiltration step. The purity of the IgG was > 95% in one step and nearly 99% with a second polishing run.
KW - Affinity Chromatography
KW - Glass
KW - Purification
KW - Antibodies
KW - Solid support
KW - HPLC
KW - FPLC
KW - Separation
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-529117
DO - https://doi.org/10.20944/preprints202103.0298.v1
SN - 2310-287X
N1 - Geburtsname von Ponader, Marco: Wilke, M. - Birth name of Ponader, Marco: Wilke, M.
SP - 1
EP - 17
PB - MDPI
CY - Basel
AN - OPUS4-52911
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kabelitz, Anke
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Joester, Maike
A1 - Reinholz, Uwe
A1 - Radtke, Martin
A1 - Bienert, Ralf
A1 - Schulz, K.
A1 - Schmack, R.
A1 - Kraehnert, R.
A1 - Emmerling, Franziska
T1 - Time-resolved in situ studies on the formation mechanism of iron oxide nanoparticles using combined fast-XANES and SAXS
N2 - The reaction of iron chlorides with an alkaline reagent is one of the most prominent methods for the synthesis of iron oxide nanoparticles. We studied the particle formation mechanism using triethanolamine as reactant and stabilizing agent. In situ fast-X-ray absorption near edge spectroscopy and small-angle X-ray scattering provide information on the oxidation state and the structural information at the same time. In situ data were complemented by ex situ transmission electron microscopy, wide-angle X-ray scattering and Raman analysis of the formed nanoparticles. The formation of maghemite nanoparticles (γ-Fe2O3) from ferric and ferrous chloride was investigated. Prior to the formation of these nanoparticles, the formation and conversion of intermediate phases (akaganeite, iron(II, III) hydroxides) was observed which undergoes a morphological and structural collapse. The thus formed small magnetite nanoparticles (Fe3O4) grow further and convert to maghemite with increasing reaction time.
KW - oxidation state
KW - structural information
KW - maghemite
PY - 2015
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-351376
DO - https://doi.org/10.1039/C5CE01585E
SN - 1466-8033
VL - 17
IS - 44
SP - 8463
EP - 8470
CY - London, UK
AN - OPUS4-35137
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wilke, Manuel
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Reinholz, Uwe
A1 - Rademann, Klaus
A1 - Emmerling, Franziska
T1 - The structure and in situ synthesis investigation of isomorphic mononuclear molecular metal phenylphosphonates
N2 - We describe a fast and effective synthesis for molecular metal phosphonates. Isomorphic compounds [M(II)(HO₃PPh)₂(H₂O₃PPh)₂(H₂O)₂] (M = Mn (1), Co (2), Ni (3); Ph = C₆H₅) were obtained by grinding. The complexes are mononuclear compounds containing neutral and monodeprotonated phenylphosphonic acid and water as ligands. The crystal structures were determined using powder X-ray diffraction (PXRD) data and validated by extended X-ray absorption fine structure (EXAFS) data. Combined synchrotron XRD measurements and Raman spectroscopy were conducted for investigating the reactions in situ. Based on these data, the intermediates were characterized and the formation mechanism was derived.
KW - Mechanochemistry
KW - Metal phosphonate
KW - In situ
KW - XRD
PY - 2016
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-363944
DO - https://doi.org/10.1039/c6dt00787b
SN - 1477-9226
SN - 1477-9234
SN - 1364-5447
VL - 45
IS - 23
SP - 9460
EP - 9467
AN - OPUS4-36394
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wilke, Manuel
A1 - Batzdorf, Lisa
A1 - Fischer, Franziska
A1 - Rademann, Klaus
A1 - Emmerling, Franziska
T1 - Cadmium phenylphosphonates: preparation, characterisation and in situ investigation
N2 - The successful mechanochemical syntheses of three cadmium phenylphosphonates indicates that mechanochemistry is ideally suited for synthesizing metal phosphonates. With this powerful synthesis tool it is possible to synthesize rapidly and efficiently both known and novel phosphonates. The Crystal structures of the two new compounds, and, were solved from PXRD data. They contain monodeprotonated phenylphosphonate and neutral phenylphosphonic acid ligands. The synthesis pathways of all three compounds were investigated in situ. A diffusion mechanism is corroborated by our findings.
Intermediates could be detected and identified. The kinetically favored product (3) could always be detected during the syntheses. The thermodynamic stability of the compounds and the stoichiometric ratio of the starting materials are the two directing factors for the synthesis of the final products.
KW - Mechanochemistry
KW - Metal phosphonate
KW - In situ
KW - MOF
KW - XRD
PY - 2016
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-363322
DO - https://doi.org/10.1039/c6ra01080f
SN - 2046-2069
VL - 6
IS - 42
SP - 36011
EP - 36019
PB - Royal Soc Chemistry
CY - Cambridge, UK
AN - OPUS4-36332
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Radtke, Martin
A1 - Reinholz, Uwe
A1 - Riesemeier, Heinrich
A1 - Emmerling, Franziska
T1 - Time- & spatial-resolved X-ray absorption fine structure (XAFS) spectroscopy in a single-shot – new analytical possibilities for in situ material characterization
N2 - A new concept that comprises both time- and lateral-resolved X-ray absorption fine-structure information simultaneously in a single shot is presented. This uncomplicated set-up was tested at the BAMline at BESSY-II (Berlin, Germany). The primary broadband beam was generated by a double multilayer monochromator. The transmitted beam through the sample is diffracted by a convexly bent Si (111) crystal, producing a divergent beam. This, in turn, is collected by either an energy-sensitive area detector, the so-called color X-ray camera, or by an area-sensitive detector based on a CCD camera, in θ-2θ geometry. The first tests were performed with thin metal foils and some iron oxide mixtures. A time resolution of lower than 1 s together with a spatial resolution in one dimension of at least 50 µm is achieved.
KW - Time resolution
KW - Single-shot XAFS
PY - 2016
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-370892
DO - https://doi.org/10.1107/S1600577516003969
SN - 1600-5775
IS - 23
SP - 769
EP - 776
PB - International Union of Crystallography
CY - Chester, UK
AN - OPUS4-37089
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fischer, Franziska
A1 - Scholz, G.
A1 - Benemann, Sigrid
A1 - Rademann, K.
A1 - Emmerling, Franziska
T1 - Evaluation of the formation pathways of cocrystal polymorphs in liquid-assisted syntheses
N2 - The synthesis of the polymorphic cocrystal caffeine:anthranilic acid was investigated to obtain a better understanding of the processes leading to the formation of different polymorphic forms. In the case of these cocrystal polymorphs synthesized by liquid-assisted grinding a distinct influence of the dipole moment of the solvent was found. A pre-coordination between the solvent molecules and the caffeine:anthranilic acid cocrystal could be identified in the formation of form II. In the case of form II the solvent can be regarded as a catalyst. The formation pathway of each polymorph was evaluated using synchrotron X-ray diffraction.
KW - cocrystal
KW - synchrotron X-ray diffraction
KW - caffeine
PY - 2014
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-313222
DO - https://doi.org/10.1039/c4ce00472h
SN - 1466-8033
VL - 16
IS - 35
SP - 8272
EP - 8278
CY - London, UK
AN - OPUS4-31322
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fischer, Franziska
A1 - Scholz, G.
A1 - Batzdorf, Lisa
A1 - Wilke, Manuel
A1 - Emmerling, Franziska
T1 - Synthesis, structure determination, and formation of a theobromine: oxalic acid 2:1 cocrystal
N2 - The structure and the formation pathway of a new theobromine : oxalic acid (2 : 1) cocrystal are presented. The cocrystal was synthesised mechanochemically and its structure was solved based on the powder X-ray data. The mechanochemical synthesis of this model compound was studied in situ using synchrotron XRD. Based on the XRD data details of the formation mechanism were obtained. The formation can be described as a self-accelerated ('liquid like') process from a highly activated species.
KW - ssNMR spectroscopy
KW - Synchrotron measurements
KW - API molecule
PY - 2015
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-331567
DO - https://doi.org/10.1039/c4ce02066a
SN - 1466-8033
VL - 17
IS - 4
SP - 824
EP - 829
CY - London, UK
AN - OPUS4-33156
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Abbott, A. P.
A1 - Abolibda, T. Z.
A1 - Davis, S.J.
A1 - Emmerling, Franziska
A1 - Lourdin, D.
A1 - Leroy, E.
A1 - Wise, W. R.
T1 - Glycol based plasticisers for salt modified starch
N2 - Starch is one of the most common and easily obtained natural polymers, making it attractive as a potential bio-based alternative to synthetic polymers. This study shows that a simple quaternary ammonium salt combined with urea or glycols forms effective modifiers that produce flexible plastics with good mechanical properties that are comparable to some polyolefin plastics. The processing conditions are shown to significantly affect the structure of the polymer which has a concomitant effect upon the mechanical and physical properties of the resulting plastic. Using a glycerol based modifier results in a totally sustainable and biodegradable material which can be injection moulded.
KW - biodegradable material
KW - flexible plastics
KW - injection moulded
PY - 2014
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-351426
DO - https://doi.org/10.1039/C4RA06220E
SN - 2046-2069
VL - 4
IS - 76
SP - 40421
EP - 40427
PB - RSC Publishing
CY - London
AN - OPUS4-35142
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - INPR
A1 - Morcillo, Dalia
A1 - Oelze, Marcus
A1 - Seena Prem, Pranav
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Emmerling, Franziska
A1 - Recknagel, Sebastian
A1 - Panne, Ulrich
A1 - Abad Andrade, Carlos Enrique
T1 - Lithium isotope fractionation as an early indicator of degradation mechanisms in lithium-ion batteries
N2 - Aging in lithium-ion batteries (LIBs) degrades performance and hinders sustainability, demanding advanced diagnostics for early failure prediction. We investigate lithium isotope fractionation (LIF) as an innovative probe of degradation in lithium cobalt oxide (LCO) coin cells aged over 0−700 cycles. High-precision multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) quantified δ7Li variations across cell stages: non-cycled (0 cycles), newly formed (5 cycles), semi-aged (250 cycles), and fully aged (700 cycles). During early cycling (≤ 45 cycles), chemical processes drive 7Li enrichment at the anode (δ7Li vs LSVEC = +12 ‰) through solid electrolyte interphase (SEI) formation, while the cathode depletes in 7Li (δ7Li vs LSVEC = −0.7 ‰). Beyond 45 cycles, electric field-induced migration predominates, promoting 6Li intercalation into the anode and increasing the δ7Li of the cathode by 8.1 ‰. Mass balance verifies isotope conservation, attributing shifts to redistribution and trapping. Complementary electrochemical impedance spectroscopy (EIS) and X-ray absorption spectroscopy and diffraction confirm SEI expansion, cobalt oxidation, lattice shrinkage, and changes in electrode structure, corroborating LIF trends. Notably, a δ7Li inflection at approximately 270 cycles anticipates end-of-life by 70 cycles, surpassing traditional methods in sensitivity. LIF emerges as a predictive indicator of aging mechanisms, informing optimized designs for durable LIBs.
KW - Lithium isotope fractionation
KW - Lithium-ion batteries
KW - Degradation mechanisms
KW - LiCoO2 cathodes
KW - LCO
KW - Isotopic tracing
KW - Lithium isotopes
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-650945
DO - https://doi.org/10.26434/chemrxiv-2025-16lvq
SP - 1
EP - 19
AN - OPUS4-65094
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hoque, Maroof Arshadul
A1 - Sommerfeld, Thomas
A1 - Lisec, Jan
A1 - Das, Prasenjit
A1 - Prinz, Carsten
A1 - Heinekamp, Christian
A1 - Stolar, Tomislav
A1 - Etter, Martin
A1 - Rosenberger, David
A1 - George, Janine
A1 - Bhattacharya, Biswajit
A1 - Emmerling, Franziska
T1 - Mechanochemically Synthesized Covalent Organic Framework Effectively Captures PFAS Contaminants
N2 - Per‐ and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants that pose significant health risks, prompting urgent efforts to develop effective removal methods and adsorbers. Covalent organic frameworks (COFs) are metal‐free adsorbers with high stability and tunable porosity. A highly crystalline COF is synthesised mechanochemically using 1,3,5‐tris(4‐aminophenyl)benzene (TAPB) and 1,3,5‐triformylbenzene (TFB). The formation dynamics are monitored in real time with time‐resolved in situ synchrotron X‐ray diffraction. The TAPB‐TFB COF demonstrates good efficiency in eliminating PFAS from water. Perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) are effectively extracted, and most of the adsorption occurred within the first 10 min. Additionally, X‐ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and DFT calculations are employed to elucidate the molecular interactions between PFAS and the COF framework. The rapid and efficient removal of PFAS makes TAPB‐TFB COF a promising material for water treatment applications.
KW - COFs
KW - Ball-milling
KW - PFAS
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-648712
DO - https://doi.org/10.1002/smll.202509275
SN - 1613-6810
VL - 21
IS - 44
SP - 1
EP - 8
PB - Wiley
CY - Weinheim
AN - OPUS4-64871
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kulow, Anicó
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Reinholz, Uwe
A1 - Emmerling, Franziska
A1 - Hampel, S.
A1 - Fittschen, U.E.A.
A1 - Streli, C.
A1 - Radtke, Martin
T1 - Comparison of three reconstruction methods based on deconvolution, iterative algorithm and neural network for X-ray fluorescence imaging with coded apertures
N2 - X-ray imaging methods are used in many fields of research, as they allow a non-destructive Investigation of the elemental content of various samples. As for every imaging method, for X-ray imaging the optics are of crucial importance. However, these optics can be very expensive and laborious to build, as the requirements on surface roughness and precision are extremely high. Angles of reflection and refraction are often in the range of a few mrad, making a compact design hard to achieve. In this work we present a possibility to simplify X-ray imaging. We have adapted the coded aperture method, a high energy radiation imaging method that has its origins in astrophysics, to full field X-ray fluorescence imaging. In coded aperture imaging, an object is projected through a known mask, the coded aperture, onto an area sensitive detector. The resulting image consists of overlapping projections of the object and a reconstruction step is necessary to obtain the information from the recorded image. We recorded fluorescence images of different samples with an energy-dispersive 2D detector (pnCCD) and investigated different reconstruction methods. With a small coded aperture with 12 holes we could significantly increase the count rate compared to measurements with a straight polycapillary optic. We show that the reconstruction of two different samples is possible with a deconvolution approach, an iterative algorithm and a neural network. These results demonstrate that X-ray fluorescence imaging with coded apertures has the potential to deliver good results without scanning and with an improved count rate, so that measurement times can be shortened compared to established methods.
KW - X-ray fluorescence imaging
KW - Coded apertures
KW - Imaging
KW - Elemental mapping
KW - Image reconstruction
PY - 2020
DO - https://doi.org/10.1039/d0ja00146e
VL - 35
IS - 7
SP - 1423
EP - 1434
PB - Royal Society of Chemistry
CY - United Kingdom
AN - OPUS4-51518
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Al-Terkawi, Abdal-Azim
A1 - Prinz, Carsten
A1 - Scholz, Gudrun
A1 - Kemnitz, Erhard
A1 - Emmerling, Franziska
T1 - Ca-, Sr-, and Ba-Coordination polymers based on anthranilic acid via mechanochemistry
N2 - Ca-, Sr-, and Ba-Based coordination polymers (CPs) were prepared mechanochemically by milling metal-hydroxide samples with anthranilic acid (oABAH). {[Ca(oABA)2(H2O)3]}n consists of one-dimensional polymeric chains that are further connected by a hydrogen-bonding network. {[Sr(oABA)2(H2O)2]·H2O}n is a one-dimensional CP in which water molecules bridge Sr2+ ions and increase the dimensionality by building an extended network. {[Ba(oABA)2(H2O)]}n crystallizes as a two-dimensional CP comprising one bridging water molecule. The cation radii influence the inorganic connectivity and dimensionality of the resulting crystal structures. The crystal structures were refined from powder X-ray diffraction data using the Rietveld method. The local coordination environments were studied via extended X-ray absorption fine structure (EXAFS) measurements. The compounds were further characterized using comprehensive analytical methods such as elemental analysis, thermal analysis, MAS NMR, imaging, and dynamic vapor sorption (DVS) measurements. Compounds 1, 2, and 3 exhibit small surface areas which decrease further after thermal annealing experiments. All compounds exhibit a phase transformation upon heating, which is only reversible in 3.
KW - Mechanochemistry
KW - XRD
PY - 2019
DO - https://doi.org/10.1039/c9dt00991d
SN - 1477-9226
SN - 1477-9234
VL - 48
IS - 19
SP - 6513
EP - 6521
PB - Royal Society of Chemistry
AN - OPUS4-48014
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Beyer, Sebastian
A1 - Prinz, Carsten
A1 - Schürmann, Robin
A1 - Feldmann, Ines
A1 - Zimathies, Annett
A1 - Blocki, Anna
A1 - Bald, Ilko
A1 - Schneider, Rudolf
A1 - Emmerling, Franziska
T1 - Ultra-sonication of ZIF-67 crystals results in ZIF-67 nano-flakes
N2 - Zeolitic Imidazolate Frameworks (ZIFs) are crystalline materials
that comprise of metal nodes and Imidazole derivatives as
linkers. ZIF-67 is often used in polymer composite materials
e. g. for gas separation membranes. Post-synthesis treatment of
ZIF-67 crystals with ultrasound leads to unforeseen plasticity
that resulted in sintered ZIF-67 and ZIF-67 nano-flakes.
Consequently, ultrasound increases the external surface area of
ZIF-67 which might improve e.g. blending with polymers in
composite materials. These new morphologies of ZIF-67 were
characterized by transmission electron, scanning electron, and
atomic force microscopy. The ultrasound treatment of ZIF-67
did not result in the formation of an amorphous framework or
a meta-stable crystal structure as indicated by powder x-ray
diffraction. In addition, ultra-sonicated ZIF-67 retained the high
gas adsorption capacity and pore size compared to synthesized
ZIF-67. The morphological changes are hard to detect with
standard analytical methods that are usually utilized for MOF
characterization. These findings also suggest that sonochemical
treatment of ZIFs leads to structural effects beyond increasing
the amount of nucleation clusters during sono-chemical synthesis,
which is currently not addressed in the field.
KW - ZIF
PY - 2016
DO - https://doi.org/10.1002/slct.201601513
SN - 2365-6549
VL - 1
IS - 18
SP - 5905
EP - 5908
AN - OPUS4-38496
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Radtke, Martin
A1 - Yusenko, Kirill
A1 - Stawski, Tomasz
A1 - Kulow, Anicó
A1 - Cakir, Cafer Tufan
A1 - Röder, Bettina
A1 - Naese, Christoph
A1 - Britzke, Ralf
A1 - Sintschuk, Michael
A1 - Emmerling, Franziska
T1 - BAMline - A real-life sample materials research beamline
N2 - With increasing demand and environmental concerns, researchers are exploring new materials that can perform as well or better than traditional materials while reducing environmental impact. The BAMline, a real-life sample materials research beamline, provides unique insights into materials’ electronic and chemical structure at different time and length scales. The beamline specializes in x-ray absorption spectroscopy, x-ray fluorescence spectroscopy, and tomography experiments. This enables real-time optimization of material properties and performance for various applications, such as energy transfer, energy storage, catalysis, and corrosion resistance. This paper gives an overview of the analytical methods and sample environments of the BAMline, which cover non-destructive testing experiments in materials science, chemistry, biology, medicine, and cultural heritage. We also present our own synthesis methods, processes, and equipment developed specifically for the BAMline, and we give examples of synthesized materials and their potential applications. Finally, this article discusses the future perspectives of the BAMline and its potential for further advances in sustainable materials research.
KW - Extended X-ray absorption fine structure
KW - Energy storage
KW - Environmental impacts
KW - Nondestructive testing techniques
KW - X-ray fluorescence spectroscopy
KW - Corrosion
KW - Near edge X-ray absorption fine structure spectroscopy
KW - X-ray absorption spectroscopy
PY - 2023
DO - https://doi.org/10.1063/5.0157194
VL - 158
IS - 24
SP - 1
EP - 22
PB - AIP Publishing
AN - OPUS4-57824
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 - 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 - Wiesner, Yosri
A1 - Altmann, Korinna
A1 - Braun, U.
T1 - Determination of Microplastic Mass Content by Thermal Extraction Desorption Gas Chromatography– Mass Spectrometry
N2 - The scientific and practical challenge of detecting microplastics (MPs) in the environment in a targeted and rapid manner is solved by innovative coupling of thermogravimetric analysis with mass spectrometric methods.
Fast identification and quantitative determination of most thermoplastic polymers and elastomers is possible by using thermal extraction Desorption gas chromatography–mass spectrometry (TED-GC–MS).
KW - Microplastics
KW - Mikroplastik
KW - TED-GC/MS
KW - Microplastics analytic
KW - Mikroplastik Massegehalt
PY - 2021
VL - 17
IS - 3
SP - 2
EP - 7
PB - MultiMedia (UK) LLC
CY - Cranbury
AN - OPUS4-52570
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Eisentraut, Paul
A1 - Altmann, Korinna
T1 - Repräsentative Mikroplastik-Detektion in Umweltproben - Weiterentwicklung der TED-GC/MS
N2 - Die große Herausforderung in der Detektion von Mikroplastik (MP)‑Partikeln (1-1000 µm) besteht darin, sie neben Millionen von natürlichen Partikeln in Umweltproben nachzuweisen. Zum Aufspüren von Senken, Eintragspfaden und für Monitoring-Kampagnen ist ein schnelles, automatisiertes Verfahren unerlässlich. Ein solches Verfahren wurde an der Bundesanstalt für Materialforschung und -prüfung (BAM) mit der ThermoExtraktion/Desorption-Gaschromatographie-Massenspektrometrie (TED-GC/MS) in den letzten Jahren entwickelt.
KW - Mikroplastik
KW - TED-GC/MS
PY - 2021
UR - https://analyticalscience.wiley.com/do/10.1002/was.0004000195
SN - 0016-3538
SP - 2
EP - 5
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-54266
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Altmann, Korinna
T1 - PlasticTrace WP1 – Stakeholder Workshop
N2 - The talk summarizes the achievments of WP1 of the PlasticTrace project. Microplastic reference materials were developed by producing tablets. Different preparation methods were compared. Characterisation of the tablets was done after filtration with µFTIR, QCL, µRaman, Py-GC/MS and TED-GC/MS after ISO standards ISO 16094-2 and ISO/FDIS 16094-3. Polymer types are polypropylene and polyethylene terephthalate.
T2 - Stakeholder Workshop PlasticsTrace
CY - Online meeting
DA - 09.09.2025
KW - Microplastics
KW - Reference materials
KW - TED-GC/MS
KW - PET
PY - 2025
AN - OPUS4-64258
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Prinz, Carsten
T1 - Importance of stability studies on porous certified reference materials
N2 - In the development of certified reference materials (CRM), it is necessary to examine appropriate materials in advance for homogeneity and stability to meet the criteria of a CRM.
In this case, the materials properties are characterized at the actual time without being possible to give a prognosis for suitability in the following years.
It is, therefore, necessary to follow the certified material parameters via a monitoring system over the years on sale.
For the current development of CRMs, the gained experience from long-term stability studies about the first generation of porous CRMs is significant. This experience is useful to better assess the suitability of candidate materials and thus develop higher quality CRMs in the future.
A comparison between the gas sorption CRM materials silica, activated carbons, alpha alumina and anatase titanium oxides will illustrate the importance of long-term stability studies on porous CRMs.
T2 - BERM 2018 - 15th International Symposium on Biological and Environmental Reference Materials
CY - Berlin, Germany
DA - 23.09.2018
KW - Reference material
KW - Monitoring
KW - Long-term stability
PY - 2018
AN - OPUS4-46257
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Rautenberg, Max
T1 - Metal phosphonates as proton conductors and ORR catalysts
N2 - Metal phosphonates are promising materials for applications in fuel cells, due to their high proton conductivity and higher chemical and thermal stability compared to the industry standard (e.g. Nafion®). Additionally, metal phosphonates are precursors to porous carbon materials with evenly distributed centers for ORR catalysis. As a fast and sustainable synthesis, mechanochemistry is the synthesis method of choice. Thorough characterization is carried out by XRD, MAS-NMR, XAS, BET, and DVS.
T2 - 2nd European Workshop on Metal Phosphonates
CY - Berlin, Germany
DA - 24.09.2019
KW - Phosphonates
KW - Proton cunductor
KW - Oxygen reduction reaction
KW - Catalysis
KW - Mechanochemistry
PY - 2019
AN - OPUS4-50257
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sobina, E.
A1 - Zimathis, Anett
A1 - Prinz, Carsten
A1 - Emmerling, Franziska
A1 - de Santis Neves, R.
A1 - Galhardo, C. E.
A1 - De Robertis, E.
A1 - WANG, H.
A1 - Mizuno, K.
A1 - Kurokawa, A.
A1 - Unger, Wolfgang
T1 - Final report of CCQM-K136 measurement of porosity properties (specific adsorption, BET specific surface area, specific pore volume and pore diameter) of nanoporous Al2O3
N2 - The CCQM-K136 key comparison for determination of the porosity properties of aluminum oxide has been organized jointly by the surface and micro/nano analysis working groups of CCQM to test the abilities of the metrology institutes to measure the porosity properties (specific adsorption, BET specific surface area, specific pore volume and pore diameter) of nanoporous Al2O3.
Ural Scientific Research Institute for Metrology (UNIIM) acted as the coordinating laboratory for this comparison with BAM Federal Institute for Materials Research and Testing (BAM) as co-coordinating laboratory. Five NMIs and one DI participated in this key comparison. All participants used a gas adsorption method, here nitrogen adsorption at 77.3 K, for analysis according to the international standards ISO 15901-2 and 9277.
KW - BET specific surface area
KW - Specific adsorption
KW - Pore diameter
KW - Specific pore volume
KW - Nanoporous Al2O3
PY - 2016
UR - http://iopscience.iop.org/article/10.1088/0026-1394/53/1A/08014
DO - https://doi.org/10.1088/0026-1394/53/1A/08014
SN - 0026-1394
SN - 1681-7575
VL - 2016
IS - 53 Technical Supplement
SP - Article 08014, 1
EP - 39
PB - IOPscience
AN - OPUS4-38282
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Miclea, P-T
T1 - Evaluation of Toxicological Characteristics of Airborne Nano/Microplastic Particles From the Industrial Environment
N2 - Micro and nano plastic (MNPs) particles and fibres represent a global scale contamination source with hazard potential. They can be identified all around our environment, even in air, soil and water. One of the major global MNPs polluters is the textile industry, which generates plastic particles (nylon, polyester, polyurethane, polyolefin, acrylic etc.) during the manufacturing processes. The study analyses the level of particle concentration outside a company that processes textile yarns, but also from the proximity of workplaces using an online air samplers with cascade and mono filter holders for silicon (Si) and quartz filters, respectively. A laser detector was used for real- time counting of particles of six size classes (PM0.3-PM10). Silicon (Si) filters with a diameter of 9 mm and pore sizes of 10 µm and 1 µm and quartz filters with a diameter of 25 mm and a pore size of 1.2 µm were used for particle sampling. A special holder was designed and made for selective sampling (PM10 and PM1.0) on Si filters. Quartz filters were pre-calcined (8000C) before collection. Sampling parameters: airflow (GilAir Plus pump) -2 l/m3, collection time -3 hours; starting time 7.00 am (T1)/2.00 pm (T2), intermittent natural ventilation, average temperature and humidity: 23.3 0C, RH: 52.5%. The weight of particles collected (µg) on the quart filters was 4.9E-05 (T1) and 5.1E-05 (T2) and on the Si filters 3,2 E-05(T1) and 5E-06(T2). The total number of the outside particles (PM0,3-PM10) was situated between 3584,58 (T1)-15165,05(T2) and inside 9901(T1) and 12921,61(T2). The highest number of PM 10 particles inside was 72/m3 and of PM0.3 particles 71979/m3. The samples were characterized using electron microscopy and µRaman spectroscopy. All samples showed a high concentration of particles on the filter. Samples show only particles with irregular shapes. The equivalent particle diameter was for PM10: 1-5 µm and PM1<1 µm. The total Ion Chromatogram shows the presence of PET-type polymer and the TED GS-MS analysis shows that the weight of the collected particles is PET. After extracting the particles from the quartz filters, they were tested for evaluation of the cytotoxic potential of preparations on human monocyte-macrophage cell cultures and peripheral lymphocytes. In the first case, the level of cytotoxicity was at the border between non-cytotoxic and cytotoxic and in the second test the result was moderate cytotoxic.
T2 - SETAC Europe 2025
CY - Vienna, Austria
DA - 11.05.2025
KW - Microplastics
KW - TED-GC/MS
KW - Nanoplastics
KW - Raman microscopy
PY - 2025
AN - OPUS4-63378
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Nusser, K.
A1 - Mosbauer, T.
A1 - Schneider, G. J.
A1 - Brandt, K.
A1 - Weidemann, Gerd
A1 - Goebbels, Jürgen
A1 - Riesemeier, Heinrich
A1 - Göritz, D.
T1 - Silica dispersion in styrene butadiene rubber composites studied by synchrotron tomography
N2 - By means of synchrotron X-ray computed tomography, model composites consisting of silica and styrenebutadiene rubber were studied with a very high spatial resolution. By our analysis technique we were able to determine the nano- and micro dispersion from the experimental results by our numerical analysis. These results are discussed with respect to crucial advantages of the generically 3-dimensional tomography technique as compared to 2-dimensional methods. Our quantitative analysis of the 3d images demonstrates that in the case of our model composites the filler dispersion is good, independent on the filler concentration. Our new 3-dimensional results evidence that considering only 2-d pictures may lead to ambiguities that can lead to wrong conclusions.
KW - X-ray tomography
KW - Silica
KW - Styrene butadiene rubber
KW - Dispersion
PY - 2012
DO - https://doi.org/10.1016/j.jnoncrysol.2011.10.009
SN - 0022-3093
VL - 358
IS - 3
SP - 557
EP - 563
PB - North-Holland Publ. Co.
CY - Amsterdam
AN - OPUS4-26105
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stawski, Tomasz
A1 - Smales, Glen Jacob
A1 - Scoppola, E.
A1 - Jha, D.
A1 - Morales, L. F. G.
A1 - Moya, A.
A1 - Wirth, R.
A1 - Pauw, Brian Richard
A1 - Emmerling, Franziska
A1 - Van Driessche, A. E. S.
T1 - Seeds of imperfection rule the mesocrystalline disorder in natural anhydrite single crystals
N2 - In recent years, we have come to appreciate the astounding intricacies associated with the formation of minerals from ions in aqueous solutions. In this context, a number of studies have revealed that the nucleation of calcium sulfate systems occurs nonclassically, involving the aggregation and reorganization of nanosized prenucleation species. In recent work, we have shown that this particle-mediated nucleation pathway is actually imprinted in the resultant micrometer-sized CaSO4 crystals. This property of CaSO4 minerals provides us with the unique opportunity to search for evidence of nonclassical nucleation pathways in geological environments.
In particular, we focused on large anhydrite Crystals extracted from the Naica Mine in Mexico. We were able to shed light on this mineral's growth history by mapping defects at different length scales. Based on this, we argue that the nanoscale misalignment of the structural subunits, observed in the initial calcium sulfate crystal seeds, propagates through different length scales both in morphological, as well as in strictly crystallographic aspects, eventually causing the formation of large mesostructured single crystals of anhydrite. Hence, the nonclassical nucleation mechanism introduces a “seed of imperfection,” which leads to a macroscopic “single” crystal whose fragments do not fit together at different length scales in a self-similar manner. Consequently, anisotropic voids of various sizes are formed with very welldefined walls/edges. However, at the same time, the material retains in part its single crystal nature.
KW - Calcium sulfate
KW - Anhydrite
KW - Mesocrystal
KW - Nucleation
KW - Naica
PY - 2021
DO - https://doi.org/10.1073/pnas.2111213118
SN - 0027-8424
VL - 118
IS - 48
SP - 1
EP - 11
PB - National Academy of Sciences (USA)
CY - Washington
AN - OPUS4-53820
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Juribašić, M.
A1 - Halasz, I.
A1 - Budimir, A.
A1 - Užarević, K.
A1 - Lukin, S.
A1 - Monas, A.
A1 - Emmerling, Franziska
A1 - Plavec, J.
A1 - Ćurić, M.
T1 - Reversible Gas−Solid Ammonia N−H Bond Activation Mediated by an Organopalladium Complex
N2 - N−H bond activation of gaseous ammonia is achieved at room temperature in a reversible solvent-free reaction using a solid dicyclopalladated azobenzene complex. Monitoring of the gas−solid reaction in real-time by in situ solid-state Raman spectroscopy enabled a detailed insight into the stepwise activation pathway proceeding to the final amido complex via a stable diammine intermediate. Gas−solid synthesis allowed for isolation and subsequent structural characterization of the intermediate and the final amido product, which presents the first dipalladated complex with the PdII−(μ-NH2)−PdII bridge. Gas−solid reaction is readily followed via color changes associated with conformational switching of the palladated azobenzene backbone. The reaction proceeds analogously in solution and was characterized by UV−vis and NMR spectroscopies showing the same stepwise route to the amido complex. Combining the experimental data with density functional theory calculations we propose a stepwise mechanism of this heterolytic N−H bond activation assisted by exogenous ammonia.
KW - In situ
KW - Mechanochemistry
PY - 2017
DO - https://doi.org/10.1021/acs.inorgchem.7b00422
VL - 56
SP - 5342
EP - 5351
PB - American Chemical Society
CY - Washington, DC, USA
AN - OPUS4-40464
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wilke, Manuel
A1 - Bach, S.
A1 - Gorelik, T.
A1 - Kolb, U.
A1 - Tremel, W.
A1 - Emmerling, Franziska
T1 - Divalent metal phosphonates – new aspects for syntheses, in situ characterization and structure solution
N2 - Divalent metal phosphonates are promising hybrid materials with a broad field of application. The rich coordination chemistry of the phosphonate linkers enables the formation of structures with different dimensionalities ranging from isolated complexes and layered structures to porous frameworks incorporating various functionalities through the choice of the building blocks.
In brief, metal phosphonates offer an interesting opportunity for the design of multifunctional materials. Here, we provide a short review on the class of divalent metal phosphonates discussing their syntheses, structures, and applications. We present the advantages of the recently introduced mechanochemical pathway for the Synthesis of divalent phosphonates as a possibility to generate new, in certain cases metastable compounds. The benefits of in situ investigation of synthesis mechanisms as well as the implementation of sophisticated methods for the structure analysis of the resulting compounds are discussed.
KW - Metal phosphonate
KW - Mechanochemistry
PY - 2017
DO - https://doi.org/10.1515/zkri-2016-1971
SN - 2194-4946
SN - 2196-7105
VL - 232
IS - 1-3
SP - 209
EP - 222
PB - De Gruyter
AN - OPUS4-40003
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fischer, Franziska
A1 - Fendel, Nicole
A1 - Greiser, Sebastian
A1 - Rademann, Klaus
A1 - Emmerling, Franziska
T1 - Impact is important - Systematic investigation of the influence of milling balls in mechanochemical reactions
N2 - A newly established in situ technique using Raman spectroscopy was employed for the detailed kinetic investigation of mechanochemical reaction pathways. This approach was applied for the systematic investigation of the direct influence of colliding balls on the reaction rate constants of a mechanochemical cocrystallization reaction. As a model reaction, the mechanochemical cocrystallization of felodipine and the coformer imidazole was investigated. Keeping the total ball mass constant by varying the number of milling balls, our study reveals that the impact of each single collision has a more significant influence on the reaction kinetics than expected.
KW - Mechanochemistry
KW - In situ
KW - Cocrystal
PY - 2017
UR - http://pubs.acs.org/doi/abs/10.1021/acs.oprd.6b00435
DO - https://doi.org/10.1021/acs.oprd.6b00435
SN - 1083-6160
SN - 1520-586X
VL - 21
IS - 4
SP - 655
EP - 659
AN - OPUS4-40355
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Nützmann, Kathrin
T1 - Depth dependent phase identification of corrosion zones in ferritic alloys by micro-X-ray absorption near edge structure spectroscopy
N2 - Ferritic steels with chromium contents up to 13 wt% are used as materials for power plant components as boiler materials (< 2 wt% Cr) and super heater tubes (> 9 wt% Cr). These materials are subject to aggressive corrosion caused by hot gases such as CO2, H2O, O2 and SO2. Especially SO2 causes fatal corrosion even as a minor component. To examine sulfurous corrosion mechanisms, experiments with pure SO2 were conducted. A proper analysis of the material changes requires phase identification and quantification with a high lateral resolution within the corrosion scale.
T2 - ANAKON2017
CY - Tübingen, Germany
DA - 03.04.2017
KW - Corosion
KW - Steel
KW - XANES
PY - 2017
AN - OPUS4-40415
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fischer, Franziska
A1 - Lubjuhn, Dominik
A1 - Greiser, Sebastian
A1 - Rademann, K.
A1 - Emmerling, Franziska
T1 - Supply and demand in the ball mill: competitive cocrystal reactions
N2 - The stability of different theophylline cocrystals under milling conditions was investigated by competitive cocrystal reactions. To determine the most stable cocrystal form under milling conditions, the active pharmaceutical ingredient theophylline was either ground with two similar coformers (benzoic acid, benzamide, or isonicotinamide), or the existing theophylline cocrystals were ground together with a competitive coformer. All competitive reactions were investigated by in situ powder X-ray diffraction disclosing the formation pathway of the milling processes. On the basis of these milling reactions, a stability order (least to most stable) was derived: tp/bs < tp/ba < tp/ina < bs/ina.
KW - Mechanochemistry
KW - Cocrystal
KW - Milling
PY - 2016
DO - https://doi.org/10.1021/acs.cgd.6b00928
SN - 1528-7483
SN - 1528-7505
VL - 16
IS - 10
SP - 5843
EP - 5851
AN - OPUS4-38097
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fischer, Franziska
A1 - Greiser, Sebastian
A1 - Peifer, Dietmar
A1 - Jäger, Christian
A1 - Rademann, K.
A1 - Emmerling, Franziska
T1 - Mechanochemically Induced Conversion of Crystalline Benzamide Polymorphs by Seeding
N2 - Benzamide has been known for its polymorphism for almost 200 years.Three polymorphic forms are described. To date,itwas only possible to crystallizeametastable form in amixture together with the thermodynamically most stable form I. Acomplete transformation of form Iinto the metastable form III by mechanochemical treatment has been achieved. Catalytic amounts of nicotinamide seeds were used to activate the conversion by mechanochemical seeding. NMR experiments indicated that the nicotinamide molecules were incorporated statistically in the crystal lattice of benzamide form III during the conversion. The transformation pathway was evaluated using in situ powder X-ray diffraction.
KW - Nicotinamide
KW - Benzamide
KW - In situ reactions
KW - Mechanochemistry
KW - Polymorphs
PY - 2016
DO - https://doi.org/10.1002/anie.201607358
VL - 128
IS - 46
SP - 14493
EP - 14497
PB - WILEY-VCH
CY - Weinheim
AN - OPUS4-38472
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - May the Force be with you - Mechanochemical syntheses studied in situ
N2 - Mechanochemistry is a fast and efficient method applicable for the synthesis of new organic, metal-organic, and inorganic compounds. The direct monitoring of milling reactions is still challenging. The underlying reaction mechanisms remain often unclear. In the last years, have established a tandem in situ approach for investigating mechanochemical reactions using time-resolved in situ XRD coupled with Raman spectroscopy. Here, we present an in situ coupling of synchrotron XRD, Raman spectroscopy, and thermography allowing the observation of mechanochemical reactions in real time. Information on the crystalline, molecular, and temperature state of the materials during grinding could be collected. The chemical composition of the reaction mixture was found to be directly correlated with changes in the temperature profile of the reaction. Furthermore, the presented setup allows the detection of crystalline, amorphous, eutectic as well as liquid intermediates. The resulting deeper kinetic and thermodynamic understanding of milling processes is the key for future optimization of mechanochemical syntheses.
T2 - Seminar Universität Montpellier
CY - Montpellier, France
DA - 24.01.2019
KW - Mechanochemistry
KW - In situ
PY - 2019
AN - OPUS4-47261
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Emmerling, Franziska
T1 - Synchrotron X-ray Investigations
N2 - Summary of the techniques available at the BAMline and µspot BEamline.
T2 - Workshop Humboldt University and Hebrew University of Jerusalem
CY - Berlin, Germany
DA - 09.10.2018
KW - In situ
KW - XRD
PY - 2018
AN - OPUS4-46993
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -