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Corundum Particles as Trypsin Carrier for Efficient Protein Digestion
No full textReusable enzyme carriers are valuable for proteomic workflows, yet many supports are expensive or lack robustness. This study describes the covalent immobilization of recombinant trypsin on micrometer-sized corundum particles and assesses their performance in protein digestion and antibody analysis. The corundum surface was cleaned with potassium hydroxide, silanized with 3-aminopropyltriethoxysilane and activated with glutaraldehyde. Recombinant trypsin was then attached, and the resulting imines were reduced with sodium cyanoborohydride. Aromatic amino acid analysis (AAAA) estimated an enzyme loading of approximately 1 µg/mg. Non-specific adsorption of human plasma proteins was suppressed by blocking residual aldehydes with a Tris-glycine-lysine buffer. Compared with free trypsin, immobilization shifted the temperature optimum from 50 to 60 °C and greatly improved stability in 1 M guanidinium hydrochloride. Activity remained above 80 % across several reuse cycles, and storage at 4 °C preserved functionality for weeks. When applied to digesting the NISTmAb, immobilized trypsin provided peptide yields and sequence coverage comparable to soluble enzyme and outperformed it at elevated temperatures. MALDI-TOF MS analysis of Herceptin digests yielded fingerprint spectra that correctly identified the antibody and achieved >60 % sequence coverage. The combination of low cost, robustness and analytical performance makes corundum-immobilized trypsin an attractive option for research and routine proteomic workflows
Can simple exchange heuristics help us in predicting magnetic properties of solids?
No full textEnvironmental and scarcity issues of common functional magnetic materials for, e.g., permanent magnets have intensified the search for rare-earth-free alternatives. This challenge is increasingly met by machine learning of magnetic properties of transition-metal compounds. Surprisingly, bond-angle-derived features were not found to be relevant for magnetic structure prediction in previous studies using DFT-computed labels. This contrasts with the Kanamori-Goodenough-Anderson (KGA) rules of superexchange, present in every magnetism textbook.
These semiempirical rules predict whether a nearest-neighbor magnetic interaction in insulators is FM or AFM based on the bond angle, orbital symmetry, and orbital occupancy. For some cases, the rules can be simplified further to only consider the bond angle of neighboring magnetic sites (KGA rules of thumb).
We review magnetism—bond angle trends within the MAGNDATA database, the largest collection of experimentally determined magnetic structures. Observed trends follow the KGA rules of thumb, and exceptions can be rationalized. In contrast, bond angles in a popular theoretical DFT database show very different trends and do not depend on the magnetic ordering.
Building on our analysis, we engineer heuristic-derived features for the machine learning of magnetic structures. We introduce a new, informative label for predicting magnetic structures that can be extended to magnetic sites and structures of arbitrary complexity. We show that features derived from the heuristic are of high importance for this machine learning task. Beyond this, our model enables the prediction of non-collinear magnetic structures
Proposal NFDI4Chem 2025-2030 In the National Research Data Infrastructure (NFDI) — Our Vision: All Chemists Publish FAIR Data
No full textThe first funding period of NFDI4Chem established a robust foundation for research data management (RDM) in chemistry by promoting FAIR data principles and creating a cohesive infrastructure to capture well-annotated data early in the lab through electronic lab notebooks (ELNs) and making this data available in public repositories. Key achievements include standardised data formats and metadata, a federated repository environment, and improved data visibility and accessibility. Training programs and outreach have significantly increased awareness and adoption of best RDM practices. In the second funding period, the consortium aims to advance these achievements by consolidating this infrastructure, developing a model for its sustainable maintenance and operation, and fostering cultural change for its widespread adoption. Goals include ensuring seamless data workflows from laboratories to open repositories, enhancing interoperability, and supporting innovative research through AI-ready data. The work plan is organised into six task areas (TAs). TA1 (Management) provides leadership and supports all other TAs in achieving their objectives. TA2 (Smart Lab) aims to develop a fully digital research environment, including an ELN as a modular platform. This environment will support data collection, management, storage, analysis, and sharing. Integrating devices and external resources will enable seamless data transfer to repositories. TA3 (Repositories) will consolidate the repository ecosystem. The goal is to integrate repositories into a federated system for better accessibility and interoperability, ensuring long-term data availability and sustainability. TA4 (Metadata, Data Standards, and Publication Standards) focuses on developing and promoting new data and metadata standards in an international community process. This includes applying ontologies to create a semantic foundation for linking research data, making it machine-readable and enabling knowledge graphs. TA5 (Community and Training) is dedicated to fostering a cultural shift towards digital chemistry through continuous engagement, collecting requirements, and providing extensive training and support through workshops and open education resources. It will promote FAIR-compliant machine learning applications, embedding RDM into academic curricula to ensure future scientists are well-versed in these practices. TA6 (Synergies and Cross-Cutting Topics) aims to enhance collaboration across NFDI consortia and beyond. This includes developing ontologies, terminology services, the search service, and other cross-cutting solutions, integrating these developments into existing infrastructure, enabling interdisciplinary data harmonisation and fostering machine learning applications
Biocides as drivers for the Selection and evolution of antimicrobial resistance
No full textAntimicrobial resistance (AMR) is a global health problem with the environment being an important compartment for the evolution, selection and transmission of AMR. These processes are impacted by pollution with antibiotics. However, antimicrobial biocides used as disinfectants and material preservatives are major pollutants exceeding the antibiotic market in terms of chemical diversity and mass. The aim of our work is to understand the mechanisms and risks of biocides for resistance and antibiotic cross-resistance evolution in bacteria to optimize their application and safeguard their efficacy. We use adaptive laboratory evolution experiments, phenotypic characterization, single-cell analysis, whole genome sequencing, and competition experiments to investigate AMR evolution and selection of the model organism E. coli in the presence of biocides. Our work shows that biocides have the potential to affect evolutionary processes towards AMR by increasing the rates of de-novo mutation and conjugation. Importantly, widely used compounds such as chlorhexidine and quaternary ammonium compounds (QACs) affect rates of mutation and conjugation at environmentally relevant concentrations. Furthermore, we show that single-cell phenotypic heterogeneity regarding tolerance (persistence) determines survival against specific biocides including QACs and isopropanol. Mechanistic investigations reveal that known antibiotic persister mechanisms contribute to persister formation to biocides. The evolution of high-level tolerance to different biocides is linked to the initial persister level and the evolution of specific genetically encoded mechanisms related to properties of the cell envelope. Biocide-tolerant strains have a selective advantage in the presence of environmentally-relevant concentrations of antibiotics, which could lead to the stabilization of biocide tolerance in environments where biocides and antibiotics co-occur (e.g. wastewater, animal stables). Taken together, our work shows the importance of assessing the contribution of biocides on evolution and selection of AMR in the environment
Improvement of manufacturing processes of Li-ion batteries by Glow Discharge Optical Emission Spectroscopy
No full textManufacturing lithium-ion coin cells (LIBs) for scientific research demands reproducibility, precision, and thorough metrology to ensure consistent quality and performance. Glow-discharge optical emission spectroscopy (GD-OES) emerges as a crucial analytical technique in this context, providing detailed insights into elemental composition and material homogeneity [1,2].
This study focuses on using GD-OES to optimize and standardize the manufacturing processes of LIBs, emphasizing metrology and traceability to develop reproducible and high-quality batteries for research purposes.
We refined cell production by adjusting key parameters such as cathode doping, electrolyte concentration, and calendar pressing. GD-OES facilitated depth analysis of elemental composition and distribution, which is essential for identifying and maintaining optimal manufacturing conditions. Validation was achieved through electrochemical impedance spectroscopy (EIS), ensuring the quality and consistency of the manufactured batteries.
GD-OES analysis revealed critical insights into elemental uniformity and impurities, guiding adjustments significantly improving cell performance and reproducibility. The method proved fast and effective in detecting and correcting variations in the manufacturing process, leading to enhanced battery quality. To understand the aging mechanisms, GD-OES was employed for fluorine depth profiling, which is crucial for studying polymer and electrolyte degradation. We significantly enhanced fluorine detection sensitivity by substituting the argon plasma with a neon/argon mixture, providing a more accurate aging analysis.
By demonstrating the versatility and efficacy of GD-OES in optimizing LIB manufacturing processes and gaining deeper insights into aging mechanisms, this research has significant practical implications. It not only advances lab research but also offers tangible industrial benefits, including improved battery quality, extended lifespan, and enhanced performance. By ensuring metrology and traceability, GD-OES contributes to developing a robust method for the reproducible manufacturing of Li-ion coin cells, boosting innovation and sustainability in battery technology
Fire Testing of various measures to prevent spalling of CFRP-reinforced concrete
No full textIn a joint research project, an interdisciplinary team of researchers and practitioners design a new prefabricated, prestressed floor system for common building constructions. To achieve a lightweight floor element, concrete with a high compressive strength is combined with high tensile strength carbon textile reinforcement. The corrosion resistant carbon textile reinforcement consists of carbon fibres embedded in a polymer matrix. The use of Carbon Fibre Reinforced Polymer (CFRP) allows a reduction of the required concrete cover and enables the design of thin-walled and highly efficient cross-sections in a variety of shapes.
However, the use of concrete with a high compressive strength increases the risk of explosive spalling of concrete under fire exposure. Experimental studies conducted at BAM have shown that the carbon textile reinforcement creates a discontinuity in the concrete resulting in a delamination of the concrete cover. Concrete spalling also depends on the type of CFRP-reinforcement. The comparison of the specimens with different CFRP-reinforcement shows an earlier event of spalling in the case of epoxy-based CFRP.
In the 8th International RILEM Workshop on Concrete Behaviour due to Fire Exposure, fire tests on CFRP-reinforced concrete elements without and with various protection measures to prevent spalling will be presented and discussed. The protection measures include the application of an intumescent coating to the fire exposed surface as well as the use of a modified concrete mixture containing polypropylene fibres (PP-fibres). The concrete mixtures used have a maximum grain size of 2 mm and correspond to concrete grade C50/60. The specimens include variants with and without carbon textile reinforcement. Two types of textile reinforcements are investigated, i.e., acrylate-based and epoxy-based resin. The specimens have circular and square forms. The lateral surfaces of the circular specimens are enclosed by a steel ring to restrain the thermal expansion of the concrete during the fire test. In contrast, at the square specimens a free thermal expansion is allowed. The fire tests are carried out with a fire exposure in accordance to the ISO-834 fire curve and without mechanical load. During the fire test, thermocouples are used to measure the temperature within the specimen and on the unexposed surface.
The fire test results show that the intumescent coating effectively prevents the concrete spalling in both unreinforced specimens and those with acrylate-based CFRP-reinforcement. However, the intumescent coating was not able to prevent the concrete spalling at the specimens with epoxy-based CFRP-reinforcement, despite the time of the spalling was delayed compared to uncoated specimens. The specimens containing PP-fibres show no spalling, which applies to both types of carbon textile reinforcement used as well as the unreinforced variant
Sustainable energy materials and circularity
No full textLi-ion batteries (LIB) are the dominant energy storage technology and present in electrified transportation, electronic devices as well as robotics. This is due to their high energy density (300 watt-hours per kilogram), low self-discharge (1.5-2% per month), long storage life (10 years) and cyclability (500-2000 cycles). Unfortunately, these batteries require the use of scarce, toxic and unethically resourced materials for their fabrication. Furthermore, it is expected an increase of 26 million units of LIB on electric vehicles by 2030 generating a large amount of waste in a very near future. However, those end-of-life batteries can be considered an important source of metals and materials (electrolytes, binders, anodes) to be reused in other applications or incorporated in the battery supply chain. This also pushes the need to redesign the LIB components and other sustainable technologies using low-cost materials. The focus of this symposium is to bring together experts from around the world to discuss the latest advancements in sustainability of battery technologies and their impact on the future landscape of our society and environment. During the symposium, speakers will present recent research and developments in solving future and present problems derived from the exponential demand of LIB manufacturin
KorroPad®-Ein Kurzzeitprüfverfahren zur Qualitätssicherung der Oberflächen- und Schweißnahtnachbearbeitung nichtrostender Stähle
No full textDie Ausbildung einer stabilen Passivschicht ist entscheidend für den Korrosionsschutz nichtrostender Stähle. KorroPad® bietet eine schnelle, zerstörungsfreie Bewertung der Passivschichtstabilität und ist seit 2025 als DIN 50024 genormt. Die Methode ermöglicht eine 15‑minütige Vor‑Ort‑Prüfung ohne Spezialwissen und schließt die Lücke zwischen teuren Laborverfahren und fehlender prozessbegleitender Qualitätssicherung. Der Beitrag beschreibt Funktionsprinzip, Anwendung sowie Beispiele aus der Oberflächen- und Schweißnahtbearbeitun
Incipient Fires—Definition, Detection and Extinguishment by Laypersons
No full textThe earlier a fire is noticed, the less developed it is and the easier it can be prevented respectively stopped, even by laypersons. Within the research project ‘TEBRAS’ the incipient phase of fires was investigated in detail. In the course of the project, it became apparent that the definition of what exactly the incipient phase of a fire encompasses is not definite and depends on the disciplines dealing with the subject ‘fire’. Based on the results of a literature review, an inquiry under experts and laypersons as well as practical fire tests a definition for the phenomenon of the incipient fire was developed which divides it into four phases. Driving key factors for each phase are identified considering the main parameters to detect and extinguish the fire
Accelerating Sustainable Material Development with SLAMD: Case Studies Using Recycled and Bio-Based Materials
No full textAs part of the EU Reincarnate project, BAM has developed an AI-based tool that signifi-cantly accelerates the development of materials in an iterative process of laboratory work, experimental validation, and data-driven optimization. This approach has already been suc-cessfully tested and validated. In Reincarnate SLAMD is currently being applied in demon-stration projects together with two industrial partners – a recycling company specializing in construction and demolition waste and a leading supplier of cement-based building materi-als. The recycling company aims to process recycled concrete fines and glass waste into composite cements with improved performance characteristics. The building materials' manufacturer, on the other hand, aims to reuse processed concrete waste primarily as aggre-gate and to develop suitable materials for five different exposure classes. The integration of SLAMD is envisioned to enable the rapid identification of optimal material compositions that consider the performance and ecological and economic aspects.
In addition, we currently further develop in the Circular B-I/O project, a joint effort with African partners to develop alternative, more biobased building materials. The goal is to integrate agricultural residues – such as corn cobs, rice hulls, and sugarcane bagasse – into large-scale, robust supply chains for the construction industry. AI-driven decision-making will be used to create a sustainable framework to transform these seasonally variable raw materials into reliable, high-performance concrete components. Building stable ecosystems and supply chains is crucial to ensure the continuous availability of sustainable materials for a resilient and circular construction industry