TY - JOUR A1 - Steinbeck, Christoph A1 - Jung, Nicole A1 - Bach, Felix A1 - Neumann, Steffen A1 - Herres-Pawlis, Sonja A1 - Liermann, Johannes A1 - Koepler, Oliver A1 - Bannwarth, Christoph A1 - Bender, Theo A1 - Bocklitz, Thomas A1 - Boehm, Franziska A1 - Bonatto Minella, Christian A1 - Biedermann, Frank A1 - Brack, Werner A1 - Cunha, Ricardo A1 - Czodrowski, Paul A1 - Eberl, Franziska A1 - Engel, Thomas A1 - Engstfeld, Albert A1 - Fischer, Tillmann G. A1 - Friedrich, Pascal A1 - Glorious, Frank A1 - Golub, Benjamin A1 - Grathwol, Christoph A1 - Haag, Rainer A1 - Hunold, Johannes A1 - Jacob, Christoph A1 - Johannsen, Jochen A1 - Jollife, John A1 - Kast, Stefan A1 - Kettner, Carsten A1 - Kuhn, Stefan A1 - Lanza, Giacomo A1 - Lisec, Jan A1 - Manolikakes, Georg A1 - Mata, Ricardo A1 - Meiler, Jens A1 - Müller, Matthias A1 - Müller-Pfefferkorn, Ralph A1 - Ortmeyer, Jochen A1 - Patterson, Wendy A1 - Pleiss, Jürgen A1 - Riedel, Annalisa A1 - Riedel, Jens A1 - Schatzschneider, Ulrich A1 - Schuster, Leonie A1 - Seeberger, Peter A1 - Seibert, Johann-Nikolaus A1 - Stadler, Peter A1 - Zeitler, Kirsten T1 - Proposal NFDI4Chem 2025-2030 In the National Research Data Infrastructure (NFDI) — Our Vision: All Chemists Publish FAIR Data N2 - The 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. KW - Research Data Management KW - FAIR KW - Chemistry PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-648540 DO - https://doi.org/10.3897/rio.11.e177037 SN - 2367-7163 VL - 11 SP - 1 EP - 100 PB - Pensoft Publishers AN - OPUS4-64854 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Shelley, J.T. A1 - Stindt, Arne A1 - Riedel, Jens A1 - Engelhard, C. T1 - Time-resolved mass-spectral characterization of ion formation from a low-frequency, low-temperature plasma probe ambient ionization source N2 - New-found interest in the development of ionization sources for mass spectrometry, inspired by the advent of ambient desorption/ionization mass spectrometry, has led to a resurgence in plasma-source development and characterization. Dielectric-barrier discharges, particularly the low-temperature plasma (LTP) probe format, have been at the forefront of this field due to their low power consumption and relatively simple design. However, better fundamental understanding of this desorption/ionization source is needed to improve the analytical capabilities of such a device. Here, we use relatively fast (2.5 ms per spectrum) time-resolved mass spectrometry to characterize the temporal reagent-ion distribution from a low-frequency LTP probe. Different voltage waveforms were found to heavily influence the discharge properties and, consequently, ion production. Ion signals from short discharge pulses, ca. 40 µs, were found to be significantly broadened, ca. 10 ms, prior to extraction into the mass spectrometer. Additionally, higher frequencies of a sine-wave LTP produced the largest flux of reagent ions, which existed for most of the voltage waveforms. Finally, temporal signals for reagent and analyte ions were measured and related to specific ionization processes: proton transfer and charge transfer. KW - Time resolved KW - Mass spectrometry KW - Time of flight KW - Dielectric barrier discharge KW - Plasma KW - Atmospheric-pressure KW - Emission-spectrometry KW - Surface treatment PY - 2014 DO - https://doi.org/10.1039/c3ja50318f SN - 0267-9477 SN - 1364-5544 VL - 29 IS - 2 SP - 359 EP - 366 PB - Royal Society of Chemistry CY - London AN - OPUS4-30404 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Glaus, Reto A1 - Riedel, Jens A1 - Gornushkin, Igor B. T1 - Insight into the formation of molecular species in laser-induced plasma of isotopically labeled organic samples N2 - Recently, the detection of molecular species in laser-induced breakdown spectroscopy (LIBS) has gained increasing interest, particularly for isotopic analysis. In LIBS of organic materials, it is predominantly CN and C2 species that are formed, and multiple mechanisms may contribute to their formation. To gain deeper insight into the formation of these species, laser-induced plasma of 13C and 15N labeled organic materials was investigated in a temporally and spatially resolved manner. LIBS on fumaric acid with a 13C labeled double bond allowed the formation mechanism of C2 to be investigated by analyzing relative signal intensities of 12C2, 12C13C, and 13C2 molecules. In the early plasma (<5 µs), the majority of C2 originates from association of completely atomized target molecules, whereas in the late plasma, the increased concentration of 13C2 is due to incomplete dissociation of the carbon double bond. The degree of this fragmentation was found to be up to 80% and to depend on the type of the atmospheric gas. Spatial distributions of C2 revealed distinct differences for plasma generated in nitrogen and argon. A study of the interaction of ablated organics with ambient nitrogen showed that the ambient nitrogen contributed mainly to CN formation. The pronounced anisotropy of the C15N to C14N ratio across the diameter of the plasma was observed in the early plasma, indicating poor initial mixing of the plasma with the ambient gas. Overall, for accurate isotope analysis of organics, LIBS in argon with relatively short integration times (<10 µs) provides the most robust results. On the other hand, if information about the original molecular structure is of interest, then experiments in nitrogen (or air) with long integration times appear to be the most promising. KW - Laser-induzierte Plasmaspektroskopie KW - Ablation KW - Emission KW - Isotopenmarkierung PY - 2015 DO - https://doi.org/10.1021/acs.analchem.5b02926 SN - 0003-2700 SN - 1520-6882 VL - 87 IS - 19 SP - 10131 EP - 10137 PB - American Chemical Society CY - Washington, DC AN - OPUS4-35226 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmid, Thomas A1 - Hidde, Julia A1 - Grünier, Sophie A1 - Jungnickel, Robert A1 - Dariz, P. A1 - Riedel, Jens A1 - Neuhaus, B. T1 - Ageing effects in mountig media of microscope slide samples from natural history collections: A case study with Canada balsam and Permount™ N2 - Microscope slide collections represent extremely valuable depositories of research material in a natural history, forensic, veterinary, and medical context. Unfortunately, most mounting media of these slides deteriorate over time, with the reason for this not yet understood at all. In this study, Raman spectroscopy, ultraviolet–visible (UV–Vis) spectroscopy, and different types of light microscopy were used to investigate the ageing behaviour of naturally aged slides from museum collections and the experimentally aged media of Canada balsam and Permount™, representing a natural and a synthetic resin, respectively, with both being based on mixtures of various terpenes. Whereas Canada balsam clearly revealed chemical ageing processes, visible as increasing colouration, Permount™ showed physical deterioration recognisable by the increasing number of cracks, which even often impacted a mounted specimen. Noticeable changes to the chemical and physical properties of these mounting media take decades in the case of Canada balsam but just a few years in the case of Permount™. Our results question whether or not Canada balsam should really be regarded as a mounting medium that lasts for centuries, if its increasing degree of polymerisation can lead to a mount which is no longer restorable. KW - Deterioration KW - Microscope slides KW - Mounting media KW - Raman spectroscopy KW - UV–Vis spectroscopy PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-537632 DO - https://doi.org/10.3390/polym13132112 VL - 13 IS - 13 SP - 1 EP - 27 PB - MDPI CY - Basel AN - OPUS4-53763 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - van Wasen, S. A1 - You, Yi A1 - Beck, S. A1 - Riedel, Jens A1 - Volmer, D. A. T1 - Miniaturized Protein Digestion Using Acoustic Levitation with Online High Resolution Mass Spectrometry N2 - The combination of acoustically levitated droplets, mid-IR laser evaporation, and subsequent post-ionization by secondary electrospray ionization was applied for monitoring the enzymatic digestion of various proteins. Acoustically levitated droplets are an ideal, wall-free model reactor, readily allowing compartmentalized microfluidic trypsin digestions. Time-resolved interrogation of the droplets yielded real-time information on the progress of the reaction and thus provided insights into reaction kinetics. After 30 min of digestion in the acoustic levitator, the obtained protein sequence coverages were identical to the reference overnight digestions. Importantly, our results clearly demonstrate that the applied experimental setup can be used for the real-time investigation of chemical reactions. Furthermore, the described methodology only uses a fraction of the typically applied amounts of solvent, analyte, and trypsin. Thus, the results exemplify the use of acoustic levitation as a green analytical chemistry alternative to the currently used batch reactions. KW - Acoustic levitation KW - Protein analysis KW - Mass spectrometry PY - 2023 DO - https://doi.org/10.1021/acs.analchem.2c05334 VL - 95 SP - 4190 EP - 4195 PB - ACS Publications AN - OPUS4-57053 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Alcalde-Vasquez, R. A1 - Moreno-Pedraza, A. A1 - Rosas-Román, I. A1 - Guillén-Alonso, H. A1 - Riedel, Jens A1 - Partida-Martínez, L. P. A1 - Winkler, R. T1 - MoBiMS: A Modular Miniature Mass Analyzer for the Real-Time 2 Monitoring of Gases and Volatile Compounds in Biological Systems N2 - Living organisms constantly interact with their environment, including through the exchange of gases. Respiration and the release and uptake of volatile organic compounds (VOCs) create dynamic microenvironments in biological systems. Studying the kinetics of volatiles in biological systems requires expensive instruments, and data analysis is challenging. Therefore, we aimed to design a minimal analytical device for measuring the composition of gaseous mixtures in realtime. We built the ‘Modular Biological Mass Spectrometer’ (MoBiMS) from 3D-printed parts and custom sensors to fit a wide array of experimental set-ups. We tested the chemical detection range and temporal resolution of the MoBiMS employing pure compounds and complex biological samples. Compounds with a higher than 0.4 mmHg vapor pressure and a molecular weight up to 154 g/mol were reliably sensed within seconds. The generated electron impact (EI) spectra were directly comparable with standard databases like the NIST EI library. Under a direct analysis approach, the MoBiMS identified the characteristic odor of banana (Musa sp.), that is, isoamyl acetate; tracked the dynamics of CO2 release while the Alka-Seltzer® reaction occurred showed the kinetics of the transient production and consumption of carbon dioxide during photosynthesis. MoBiMS also discriminated between volatile compounds ions coming from tobacco (Nicotiana benthamiana) leaves and the surrounding air through untargeted analysis. The small footprint of the MoBiMS and its relatively low energy consumption facilitate in situ analyses, as an additional gas supply is not necessary with EI ionization. The MoBiMS is easy to assemble, and its construction and operation are very cost-efficient compared to commercial devices. The analytical performance of the MoBiMS is suitable for real-time studies of biological systems, environmental monitoring, and medical diagnostics. KW - Mass spectrometry KW - Instrumentation KW - Miniaturization KW - Volatiles PY - 2022 DO - https://doi.org/10.1016/j.microc.2021.107090 SN - 0026-265X VL - 175 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-56528 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmid, Thomas A1 - Jungnickel, R. A1 - Neuhaus, B. A1 - Riedel, Jens A1 - Kneipp, Janina A1 - Lüter, C. T1 - Raman spectroscopy as a tool for the collection management of microscope slides N2 - Throughout the history of preparation of biological samples for microscopy the choice of the mounting medium was sometimes dictated merely by availability of the used media. Thus, a plethora of resins and other organic polymers as well as complex mixtures are found to serve as mounting agents in microscope slide collections of museums of natural history, impeding the work for both curators and conservators. Dramatically, in some cases the used mounting media can already be observed to have undergone crystallization and other decomposition processes within few years of mounting demanding immediate action in restoring as well as an imminent precaution in conservation. Therefore, an unambiguous chemical identification of the used agent as well as its current aging stage is of great interest for the biologist community. The technical demands on the analytical approach to obtain this information can be straightforwardly identified. Any used technique has to be non-destructive, yield in molecular information allowing for a chemical identification of the used mounting agents and allow for a spatially well-defined interrogation in a thin sample slice, typically through a transparent cover slip. In this contribution we present a thorough study of the applicability of Raman spectroscopy for the described task. The obtained results clearly demonstrate the successful feasibility of the chosen method for a) a clear distinction between different media, b) the elucidation of the chemical composition of a multicomponent medium and c) an unambiguous identification of real unknown samples by a distinct assignment to a previously recorded spectral library. This library database was built up by recording pure mounting agents and will be provided to the general public. In combination with a Raman spectrometer, it can be an invaluable tool for future curation and conservation endeavors devoted to microscope slide collections at natural history museums. KW - Taxonomy KW - Mounting medium KW - Coverslip seal PY - 2016 DO - https://doi.org/10.1016/j.jcz.2016.07.002 SN - 0044-5231 VL - 265 SP - 178 EP - 190 PB - Elsevier AN - OPUS4-38210 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Villatoro, J. A1 - Zühlke, M. A1 - Riebe, D. A1 - Beitz, T. A1 - Weber, M. A1 - Riedel, Jens A1 - Löhmannsröben, H.-G. T1 - IR-MALDI ion mobility spectrometry: physical source characterization and application as HPLC detector N2 - Infraredmatrix-assisted laser dispersion and ionization(IR-MALDI) in combination with on mobility (IM) spectrometry enables the direct Analysis of biomolecules in aqueous solution. The release of ions directly from an aqueous solution is based on a phase explosion, induced by the Absorption of an IR laser pulse, which disperses the liquid as vapor, nano- and micro-droplets. The ionization process is characterized initially by a broad spatial distribution of the ions, which is a result of complex fluid dynamics and desolvation kinetics. These processes have a profound effect on the shape and width of the peaks in the IM spectra. In this work, the Transport of ions by the phase explosion-induced shockwave could be studied independently from the transport by the electric field. The shockwave-induced mean velocities of the ions at different time scales were determined through IM spectrometry and shadowgraphy. The results show a deceleration of the Ions from 118m∙s−1 at a distance of 400 μm from the liquid surface to 7.1 m∙s−1 at a distance of 10 mm, which is caused by a pileup effect. Furthermore, the desolvation kinetics were investigated and a first-order desolvation constant of 325 ± 50 s−1 was obtained. In the second part, the IR-MALDI-IM spectrometer is used as an HPLC detector for the twodimensional separation of a pesticide mixture. KW - Ion mobility spectrometry KW - IR-MALDI KW - Shadowgraphy KW - Laser PY - 2016 DO - https://doi.org/10.1007/s12127-016-0208-1 VL - 2016 IS - 4 SP - 197 EP - 207 PB - Springer-Verlag Berlin CY - Heidelberg AN - OPUS4-38467 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bierstedt, Andreas A1 - Riedel, Jens T1 - High-repetition rate laser ablation coupled to dielectric barrier discharge postionization for ambient mass spectrometry N2 - Most ambient sample introduction and ionization techniques for native mass spectrometry are highly selective for polar agents. To achieve a more general sensitivity for a wider range of target analytes, a novel laser ablation dielectric barrier discharge (LA DBD) ionization scheme was developed. The Approach employs a two-step mechanism with subsequent sample desorption and post-ionization. Effective Ablation was achieved by the second harmonic output (λ = 532 nm) of a diode pumped Nd:YVO₄ laser operating at a high-repetition rate of several kHz and pulse energies below 100 μJ. The ejected analytecontaining aerosol was consecutively vaporized and ionized in the afterglow of a DBD plasma jet. Depending on their proton affinity the superexcited Helium species in this afterglow produced analyte ions as protonated and ammoniated species, as well as radical cations. The optimization procedure could corroborate underlying conceptual consideration on the ablation, desorption and ionization mechanisms. A successful detection of a variety of target molecules could be shown from the pharmaceutical ibuprofen, urea, the amino acids L-arginine, L-lysine, the polymer polyethylene glycol, the organometallic compound ferrocene and the technical mixture wild mint oil. For a reliable evaluation of the introduced detection procedure spectra from the naturally abundant alkaloid capsaicin in dried capsicum fruits were recorded. KW - Laser ablation KW - High-repetition rate laser KW - Dielectric barrier discharge KW - Ambient mass spectrometry PY - 2016 DO - https://doi.org/10.1016/j.ymeth.2016.02.002 SN - 1046-2023 IS - 104 SP - 3 EP - 10 PB - Elsevier CY - Oxford AN - OPUS4-36730 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Riedel, Jens A1 - Warschat, Carsten T1 - Studying the field induced breakup of acoustically levitated drops N2 - Coulomb fission of charged droplets (The terms drop and droplet are often used synonymous. Throughout this manuscript, to avoid confusion, the terms drop and droplet will be used for liquid spheres with radii in the millimeter range and the micrometer range, respectively. In our experiments, the first correspond to the parent drop while the latter describes the ejected progeny droplets.) is a wellstudied natural phenomenon. Controlled droplet fission is already successfully employed in several technological applications. Still, since the occurring surface rupture relies on the exact understanding and description of the liquid gas boundary, some details are still under debate. Most empirical systematic studies observe falling micrometer droplets passing through the electric field inside a plate capacitor. This approach, although easily applicable and reliable, limits the experimental degrees of freedom regarding the observable time and the maximum size of the drops and can only be performed in consecutive individual observations of different subsequent drops. Here we present a novel setup to study the field induced breakup of acoustically levitated drops. The design does not bear any restrictions towards the temporal window of observation, and allows handling of drops of a tunable radius ranging from 10 µm to several millimeters and a real-time monitoring of one single drop. Our comprehensive study includes a time resolved visual inspection, laser shadowgraphy, laser induced fluorescence imaging, and ambient mass spectrometric interrogation of the nascent Taylor cone. The results shown for a millimeter sized drop, previously inaccessible for Coulomb fission experiments, are mostly comparable with previous results for smaller drops. The major difference is the time scale and the threshold potential of the drop rupture. Both values, however, resemble theoretically extrapolations to the larger radius. The technique allows for a systematic study of breakup behavior of drops of different charge, material, and size. KW - Droplet fission KW - Levitated droplets KW - Taylor limit KW - Spray PY - 2017 DO - https://doi.org/10.1063/1.5004046 SN - 0034-6748 SN - 1089-7623 VL - 88 IS - 10 SP - 105108-1 EP - 105108-6 PB - AIP publishing AN - OPUS4-42940 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ickert, Stefanie A1 - Hofmann, J. A1 - Riedel, Jens A1 - Beck, S. A1 - Pagel, K. A1 - Linscheid, M. W. T1 - Charge-induced geometrical reorganization of DNA oligonucleotides studied by tandem mass spectrometry and ion mobility N2 - Mass spectrometry is applied as a tool for the elucidation of molecular structures. This premises that gas-phase structures reflect the original geometry of the analytes, while it requires a thorough understanding and investigation of the forces controlling and affecting the gas-phase structures. However, only little is known about conformational changes of oligonucleotides in the gas phase. In this study, a series of multiply charged DNA oligonucleotides (n¼15–40) has been subjected to a comprehensive tandem mass spectrometric study to unravel transitions between different ionic gas-phase structures. The nucleobase sequence and the chain length were varied to gain insights into their influence on the geometrical oligonucleotide organization. Altogether, 23 oligonucleotides were analyzed using collision-induced fragmentation. All sequences showed comparable correlation regarding the characteristic collision energy. This value that is also a measure for stability, strongly correlates with the net charge density of the precursor ions. With decreasing charge of the oligonucleotides, an increase in the fragmentation energy was observed. At a distinct charge density, a deviation from linearity was observed for all studied species, indicating a structural reorganization. To corroborate the proposed geometrical change, collisional cross-sections of the oligonucleotides at different charge states were determined using ion mobility-mass spectrometry. The results clearly indicate that an increase in charge density and thus Coulomb repulsion results in the transition from a folded, compact form to elongated structures of the precursor ions. Our data show this structural transition to depend mainly on the charge density, whereas sequence and size do not have an influence. KW - Ion mobility KW - Collision-induced dissociation KW - Mass spectrometry KW - Oligonucleotide KW - Fragmentation KW - Tandem-MS PY - 2018 DO - https://doi.org/10.1177/1469066717746896 SN - 1469-0667 SN - 1751-6838 VL - 24 IS - 2 SP - 225 EP - 230 PB - Sage AN - OPUS4-44429 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ickert, Stefanie A1 - Riedel, Jens A1 - Beck, S. A1 - Linscheid, M. W. T1 - Negative nucleotide ions as sensitive probes for energy specificity in collision‐induced fragmentation in mass spectrometry N2 - Rationale: The most commonly used fragmentation methods in tandem mass spectrometry (MS/MS) are collision‐induced dissociation (CID) and higher energy collisional dissociation (HCD). While in CID the preselected ions in the trap are resonantly (and m/z exclusively) excited, in HCD the entire m/z range experiences the dissociative acceleration. The different excitation is reflected in different fragment distributions. Methods: As a test‐bed for particularly pronounced fragmentation specificity, here MS/MS experiments on several 4‐mer oligonucleotides were conducted employing both collision methods and the results were thoroughly compared. Oligonucleotides are shown to be sensitive probes to subtle changes, especially in the negative ion mode. A detailed analysis of these differences reveals insight into the dissociation mechanics. Results: Thedifferencesarerepresentedinheat‐maps,whichallowforadirectvisualinspection oflargeamountsofdata.Inthesefalsecolourrepresentationsthe,sometimessubtle,changesinthe individual dissociation product distributions become distinct. Another advantage of these graphic plots can be found in the formation of systematic patterns. These patterns reflect trends in dissociation specificity which allow for the formulation of general rules in fragmentation behavior. Conclusions: Instruments equipped with two different excitation schemes for MS/MS are today widely available. Nonetheless, direct comparisons between the individual results are scarcely made. Such comparative studies bear a powerful analytical potential to elucidate fragmentation reaction mechanism. KW - DNA KW - Tandem MS KW - HCD KW - CID PY - 2018 DO - https://doi.org/10.1002/rcm.8062 SN - 0951-4198 SN - 1097-0231 VL - 32 IS - 7 SP - 597 EP - 603 PB - Wiley & Sons, Ltd. AN - OPUS4-44430 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neuhaus, Birger A1 - Schmid, Thomas A1 - Riedel, Jens T1 - Collection management and study of microscope slides: Storage, profiling, deterioration, restoration procedures, and general recommendations N2 - A wide range of aspects concerning microscope slides, their preparation, long-time storage, curatorial measures in collections, deterioration, restoration, and study is summarized based on our own data and by analyzing more than 600 references from the 19th century until 2016, 15 patents, and about 100 Materials Safety Data Sheets. Information from systematic zoology, conservation sciences, chemistry, forensic sciences, pathology, paleopathology, applied sciences like food industry, and most recent advances in digital imaging are put together in order to obtain a better understanding of which and possibly why mounting media and coverslip seals deteriorate, how slides can be salvaged, which studies may be necessary to identify a range of ideal mounting media, and how microscope studies can benefit from improvements in developmental biology and related fields. We also elaborate on confusing usage of concepts like that of maceration and of clearing. The chemical ingredients of a range of mounting media and coverslip seals are identified as much as possible from published data, but this information suffers in so far as the composition of a medium is often proprietary of the manufacturer and may vary over time. Advantages, disadvantages, and signs of deterioration are documented extensively for these media both from references and from our own observations. It turns out that many media degrade within a few years, or decades at the latest, except Canada balsam with a documented life-time of 150 years, Euparal with a documented life-time of 50 years, and glycerol-paraffin mounts sealed with Glyceel, which represents almost the only non-deteriorating and easily reversible mount. Deterioration reveals itself as a yellowing in natural resins and as cracking, crystallization, shrinkage on drying or possibly on loss of a plasticizer, detachment of the coverslip, segregation of the ingredients in synthetic polymers, as well as continued maceration of a specimen to a degree that the specimen virtually disappears. Confusingly, decay does not always appear equally within a collection of slides mounted at the same time in the same medium. The reasons for the deteriorative processes have been discussed but are controversial especially for gum-chloral media. Comparing data from conservation sciences, chemical handbooks, and documented ingredients, we discuss here how far chemical and physical deterioration probably are inherent to many media and are caused by the chemical and physical properties of their components and by chemicals dragged along from previous preparation steps like fixation, chemical maceration, and physical clearing. Some recipes even contain a macerating agent, which proceeds with its destructive work. We provide permeability data for oxygen and water vapor of several polymers contained in mounting media and coverslip seals. Calculation of the penetration rate of moisture in one example reveals that water molecules reach a specimen within a few days up to about a month; this lays to rest extensive discussions about the permanent protection of a mounted specimen by a mounting medium and a coverslip seal. Based on the ever growing evidence of the unsuitable composition and application of many, and possibly almost all, mounting media, we strongly encourage changing the perspective on microscope slides from immediate usability and convenience of preparation towards durability and reversibility, concepts taken from conservation sciences. Such a change has already been suggested by Upton (1993) more than 20 years ago for gum-chloral media, but these media are still encouraged nowadays by scientists. Without a new perspective, taxonomic biology will certainly lose a large amount of its specimen basis for its research within the next few decades. Modern non-invasive techniques like Raman spectroscopy may help to identify mounting media and coverslip seals on a given slide as well as to understand ageing of the media. An outlook is given on potential future studies. In order to improve the situation of existing collections of microscope slides, we transfer concepts as per the Smithsonian Collections Standards and Profiling System, developed for insect collections more than 25 years ago, to collections of slides. We describe historical and current properties and usage of glass slides, coverslips, labels, and adhesives under conservational aspects. In addition, we summarize and argue from published and our own experimental information about restorative procedures, including re-hydration of dried-up specimens previously mounted in a fluid medium. Alternatives to microscope slides are considered. We also extract practical suggestions from the literature concerning microscope equipment, cleaning of optical surfaces, health risks of immersion oil, and recent improvements of temporary observation media especially in connection with new developments in digital software. KW - Re-hydration KW - Mounting medium KW - Coverslip seal KW - Fixation KW - Maceration KW - Clearing KW - Immersion oil KW - Permeability PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-423322 SN - 978-1-77670-222-0 SN - 978-1-77670-223-7 DO - https://doi.org/10.11646/zootaxa.4322.1.1 SN - 1175-5326 VL - 4322 IS - 1 SP - 1 EP - 173 PB - Magnolia Press CY - Auckland, Neuseeland AN - OPUS4-42332 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Riedel, Jens A1 - Larsson, H. A1 - Temps, F. A1 - Hartke, B. T1 - Resonance dynamics of DCO (<(X over tilde>(2)A') simulated with the dynamically pruned discrete variable representation (DP-DVR) N2 - Selected resonance states of the deuterated formyl radical in the electronic ground state X^2A´ are computed using our recently introduced dynamically pruned discrete variable representation [H. R. Larsson, B. Hartke, and D. J. Tannor, J. Chem. Phys. 145, 204108 (2016)]. Their decay and asymptotic distributions are analyzed and, for selected resonances, compared to experimental results obtained by a combination of stimulated emission pumping and velocity-map Imaging of the product D atoms. The theoretical results show good agreement with the experimental kinetic energy distributions. The intramolecular vibrational energy redistribution is analyzed and compared with previous results from an effective polyad Hamiltonian. Specifically, we analyzed the part of the wavefunction that remains in the interaction region during the decay. The results from the polyad Hamiltonian could mainly be confirmed. The C=O stretch quantum number is typically conserved, while the D-C=O bend quantum number decreases. Differences are due to strong anharmonic coupling such that all resonances have major contributions from several zero-order states. For some of the resonances, the coupling is so strong that no further zero-order states appear during the dynamics in the interaction region, even after propagating for 300 ps. KW - Reaction dynamics KW - Spectroscopy KW - Quantum state PY - 2018 DO - https://doi.org/10.1063/1.5026459 SN - 0021-9606 VL - 148 IS - 20 SP - 204309-1 EP - 204309-15 PB - AIP publishing CY - New York AN - OPUS4-45345 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Riedel, Jens T1 - Airborne laser spark ionization N2 - A novel ionization scheme for ambient mass spectrometry is presented and discussed. Desorption and ionization are achieved by a quasi-continuous laser induced plasma (LIP) ignited in front of the atmospheric pressure interface of a time-of-flight mass spectrometer. This setup comprises the advantages of i) an ambient probe, ii) electro neutrality, iii) low power consumption, iv) a sufficient duty cycle, v) a ubiquitous plasma medium (air) and vi) high sensitivity caused by the high electron number densities. The plasma properties and operating conditions are investigated to understand the processes that lead to the formation of molecular ions. Comprehensive studies include optical emission spectroscopy, shadowgraphic shockwave visualization and time-of-flight mass spectrometry investigations. The observed MS signal (including reagent-ion signal, as well as analyte spectra) closely resembles the ionization behavior of other electrically-driven plasma-based ionization sources, such as DBD, LTP or DART. Conversely that means that although LIPs are commonly known to have temperatures way above 10.000 K and thus efficiently atomize and ionize molecules, MS spectra were obtained that showed the formation of intact molecular ions. For an insight into the LIP properties the optical emission of the LIP is examined and exhibits a pronounced degree of dissociation into atomic and ionic species, which reflects the higher temperature and electron density inside a LIP. Accordingly, rather elemental (ICP-type) than molecular spectra should be expected. However due to the absence of such ions, we conclude that the analyte does not enter the hot center of the plasma itself. Moreover, the initial, highly-excited plasma species react cascade-like to lower energetic species via reactive collision with the surrounding atmosphere, which can then subsequently ionize molecules of interest. The concept potentially involves charge transfer, proton transfer, electron impact and photoionization. These assumptions are confirmed via the shadowgraphs of the expanding shockwave around the LIP. An effective spatial separation between the two regions is maintained by concentrically expanding pressure waves resulting in a strongly unidirectional diffusion. Additionally, the strictly outbound matter transport suggests a rarefaction inside the plasma region for each plasma event. T2 - SCIX 2017 CY - Reno, Nevada, USA DA - 08.10.2017 KW - Ambient ionization KW - Mass spectrometry KW - Laser KW - Plasma PY - 2017 UR - https://www.scixconference.org/program/final-program?symposium=17ACS01&p=8810/#session AN - OPUS4-42609 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Riedel, Jens T1 - Airborne laser spark ionization N2 - A novel ionization scheme for ambient mass spectrometry is presented and discussed. Desorption and ionization are achieved by a quasi-continuous laser induced plasma (LIP) ignited in front of the atmospheric pressure interface of a time-of-flight mass spectrometer. This setup comprises the advantages of i) an ambient probe, ii) electro neutrality, iii) low power consumption, iv) a sufficient duty cycle, v) a ubiquitous plasma medium (air) and vi) high sensitivity caused by the high electron number densities. The plasma properties and operating conditions are investigated to understand the processes that lead to the formation of molecular ions. Comprehensive studies include optical emission spectroscopy, shadowgraphic shockwave visualization and time-of-flight mass spectrometry investigations. The observed MS signal (including reagent-ion signal, as well as analyte spectra) closely resembles the ionization behavior of other electrically-driven plasma-based ionization sources, such as DBD, LTP or DART. Conversely that means that although LIPs are commonly known to have temperatures way above 10.000 K and thus efficiently atomize and ionize molecules, MS spectra were obtained that showed the formation of intact molecular ions. For an insight into the LIP properties the optical emission of the LIP is examined and exhibits a pronounced degree of dissociation into atomic and ionic species, which reflects the higher temperature and electron density inside a LIP. Accordingly, rather elemental (ICP-type) than molecular spectra should be expected. However due to the absence of such ions, we conclude that the analyte does not enter the hot center of the plasma itself. Moreover, the initial, highlyexcited plasma species react cascade-like to lower energetic species via reactive collision with the surrounding atmosphere, which can then subsequently ionize molecules of interest. The concept potentially involves charge transfer, proton transfer, electron impact and photoionization. These assumptions are confirmed via the shadowgraphs of the expanding shockwave around the LIP. An effective spatial separation between the two regions is maintained by concentrically expanding pressure waves resulting in a strongly unidirectional diffusion. Additionally, the strictly outbound matter transport suggests a rarefaction inside the plasma region for each plasma event. T2 - IPOIMS CY - Menorca, Spain DA - 16.10.2017 KW - Laser KW - Ambient ionization KW - Plasma KW - Mass spectrometry PY - 2017 UR - http://ipoims.com/downloads/Abstracts_IPOIMS_10102017.pdf AN - OPUS4-42610 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zöllner, Moritz T. A1 - Dariz, Petra A1 - Riedel, Jens A1 - Schmid, Thomas T1 - Dolomite and Mg Calcite as Mineral Thermometers in Mortar Binders. A High Resolution Raman Spectroscopic Study N2 - This paper suggests the use of high‐resolution Raman scattering bands of MgCa carbonates as posteriori thermometer minerals in archaeometric studies. Therefore, the thermal behavior of two dolomite samples and the hydration and carbonation reaction in air of the decomposition products were investigated by Raman microspectroscopy. The increase in the calcination temperature resulted in the formation of – Raman silent MgO and – inert Mg calcite at 700°C–750°C. In contrast, the decarbonation, hydration, and recarbonation of sample material exposed to 750°C–900°C in a muffle furnace led to the appearance of Mg‐free calcite. High spectral resolution Raman spectroscopy enabled a spectral distinction between these two groups due to differences in the band parameters (peak position, bandwidth) of the vibrational (v1, v4, L) modes of calcite. In combination with Raman microspectroscopic mapping, this spectral information represents a new approach for the estimation of burning temperatures of medieval high‐fired gypsum mortars via natural dolomite impurities. Thus, the results of this work highlight the importance and potential of Raman microspectroscopy as a thermometric tool for elucidating the thermal history of anthropogenic fired materials, with potential applications for archaeometry and art technology, as well as for quality controls in the frame of the production of mineral mortar binders and ceramics or bricks, respectively. KW - Mineral thermometry KW - Raman spectroscopy KW - Dolomite KW - High-fired gypsum mortar PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630270 DO - https://doi.org/10.1002/jrs.6810 SN - 1097-4555 SP - 1 EP - 13 PB - Wiley AN - OPUS4-63027 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Villatoro, J. A1 - Zühlke, M. A1 - Riebe, D. A1 - Riedel, Jens A1 - Beitz, T. A1 - Löhmannsröben, H.-G. T1 - IR-MALDI ion mobility spectrometry N2 - The novel combination of infrared matrix-assisted laser dispersion and inization (IR-MALDI) with ion mobility (IM) spectrometry makes it possible to investigate biomolecules in their natural environment, liquid water. As an alternative to an ESI source, the IR-MALDI source was implemented in an in-house-developed ion mobility (IM) spectrometer. The release of ions directly from an aqueous solution is based on a phase explosion, induced by the absorption of an IR laser pulse (λ = 2.94 μm, 6 ns pulse width), which disperses the liquid as nano- and micro-droplets. The prerequisites for the application of IR-MALDI-IM spectrometry as an analytical method are narrow analyte ion signal peaks for a high spectrometer resolution. This can only be achieved by improving the desolvation of ions. One way to full desolvation is to give the cluster ions sufficient time to desolvate. Two methods for achieving this are studied: the implementation of an additional drift tube, as in ESI-IM-spectrometry, and the delayed extraction of the ions. As a result of this optimization procedure, limits of detection between 5 nM and 2.5 μMas well as linear dynamic ranges of 2–3 orders of magnitude were obtained for a number of substances. The ability of this method to analyze simple mixtures is illustrated by the separation of two different surfactant mixtures. KW - Ion mobility KW - Spectrometry KW - IR-MALDI KW - Laser PY - 2016 DO - https://doi.org/10.1007/s00216-016-9739-x SN - 1618-2650 SN - 1618-2642 VL - 408 IS - 23 SP - 6259 EP - 6268 PB - Springer-Verlag CY - Heidelberg AN - OPUS4-37615 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bierstedt, Andreas A1 - Riedel, Jens T1 - Airborne laser-spark for ambient desorption/ionisation N2 - A novel direct sampling ionisation scheme for ambient mass spectrometry is presented. Desorption and ionisation are achieved by a quasi-continuous laser induced plasma in air. Since there are no solid or liquid electrodes involved the ion source does not suffer from chemical interferences or fatigue originating from erosive burning or from electrode consumption. The overall plasma maintains electro-neutrality, minimising charge effects and accompanying long term drift of the charged particles trajectories. In the airborne plasma approach the ambient air not only serves as the plasma medium but at the same time also slows down the nascent ions via collisional cooling. Ionisation of the analyte molecules does not occur in the plasma itself but is induced by interaction with nascent ionic fragments, electrons and/or far ultraviolet photons in the plasma vicinity. At each individual air-spark an audible shockwave is formed, providing new reactive species, which expands concentrically and, thus, prevents direct contact of the analyte with the hot region inside the plasma itself. As a consequence the interaction volume between plasma and analyte does not exceed the threshold temperature for thermal dissociation or fragmentation. Experimentally this indirect ionisation scheme is demonstrated to be widely unspecific to the chemical nature of the analyte and to hardly result in any fragmentation of the studied molecules. A vast ensemble of different test analytes including polar and non-polar hydrocarbons, sugars, low mass active ingredients of pharmaceuticals as well as natural biomolecules in food samples directly out of their complex matrices could be shown to yield easily accessible yet meaningful spectra. Since the plasma medium is humid air, the chemical reaction mechanism of the ionisation is likely to be similar to other ambient ionisation techniques. N2 - Wir stellen hier eine neue Ionisationsmethode für die Umgebungsionisation (ambient ionisation) vor. Sowohl die Desorption als auch die Ionisation erfolgen hierbei durch ein laserbetriebenes Luftplasma. Die Abwesenheit fester oder flüssiger Elektroden hat zur Folge, dass die Methode weder unter chemischen Interferenzen noch unter Verschleiß durch Korrosionsbrand oder abgetragenes Elektrodenmaterial leidet. Insgesamt betrachtet herrscht in dem Plasma Elektroneutralität, wodurch Aufladungseffekte minimiert werden, die andernfalls zu einer langfristigenÄderung der Flugbahnen von Ionen während der Experimente führen kann. In dem Ansatz eine freischwebende Luftentladung bei Atmosphärendruck zu verwenden agiert die Luft nicht nur als Plasmamedium sondert dient zusätzlich als Badgas für die stoßinduzierte Kühlung der entstehenden Ionen. Die Ionisierung der Analytmoleküle erfolgt nicht unmittelbar im Plasma sondern in dessen direkter Umgebung durch Wechselwirkung mit freigesetzten ionischen Luftspezies, freien Elektronen oder Photonen im kurzwelligen ultravioletten Bereich. Jede Laserentladung erzeugt eine hörbare Stoßwelle, in welcher neu produzierte reaktive Spezies freigesetzt werden, welche sich konzentrisch ausbreiten, so dass eine Diffusion der Analytmoleküle ins heiße Innere des Plasmas verhindert wird. Daraus folgt, dass im Interaktionsvolumen zwischen Plasma und Analyt der Temperaturgrenzwert für eine thermische Dissoziation oder Fragmentierung der Moleküle nicht überschritten wird. Experimentell konnte belegt werden, dass das vorgestellte Ionisierungsschema sehr unselektiv bezüglich der chemischen Analytklasse ist und kaum Fragmentierungsprodukte beobachtet werden können. Messungen einer breitgefächerten Auswahl unterschiedlicher Testsubstanzen, wie beispielsweise polarer und unpolarer Kohlenwasserstoffe, Zuckern, niedermolekularer pharmazeutischer Wirkstoffe, sowie natürlicher Biomoleküle in Lebensmittelproben unmittelbar aus ihren komplexen Matrizes, führten zu aussagekräftigen Massenspektren. Zumal das Lasermedium feuchte Luft ist, scheint der Reaktionsmechanismus dem anderer Atmosphärendruckionisierungsmethoden zuähneln. KW - Laser-spark KW - Laser-induced plasma KW - DPSS laser KW - High repetition rate KW - Ambient mass spectrometry KW - Time-of-flight mass spectrometry KW - Ionisation PY - 2016 DO - https://doi.org/10.1255/ejms.1417 SN - 1469-0667 VL - 22 IS - 3 SP - 105 EP - 114 PB - IM Publications LLP CY - Chichester, UK AN - OPUS4-37286 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Riedel, Jens A1 - Hoekstra, S. A1 - Jäger, W. A1 - Gilijamse, J.J. A1 - van de Meerakker, S.Y.T. A1 - Meijer, G. T1 - Accumulation of Stark-decelerated NH molecules in a magnetic trap N2 - Here we report on the accumulation of ground-state NH molecules in a static magnetic trap. A pulsed supersonic beam of NH (a1Δ) radicals is produced and brought to a near standstill at the center of a quadrupole magnetic trap using a Stark decelerator. There, optical pumping of the metastable NH radicals to the X3Σ- ground state is performed by driving the spin-forbidden A3Π ← a1Δ transition, followed by spontaneous A → X emission. The resulting population in the various rotational levels of the ground state is monitored via laser induced fluorescence detection. A substantial fraction of the groundstate NH molecules stays confined in the several milliKelvin deep magnetic trap. The loading scheme allows one to increase the phase-space density of trapped molecules by accumulating packets from consecutive deceleration cycles in the trap. In the present experiment, accumulation of six packets is demonstrated to result in an overall increase of only slightly over a factor of two, limited by the trap-loss and reloading rates. KW - Cold matter KW - Stark deceleration KW - Trapping of polar molecules KW - NH KW - High resolution spectroscopy KW - Fluorescence KW - Radical PY - 2011 DO - https://doi.org/10.1140/epjd/e2011-20082-7 SN - 1434-6060 VL - 65 IS - 1-2 SP - 161 EP - 166 PB - Springer CY - Berlin AN - OPUS4-25050 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Michalik-Onichimowska, Aleksandra A1 - Kern, Simon A1 - Riedel, Jens A1 - Panne, Ulrich A1 - King, R. A1 - Maiwald, Michael T1 - ‘‘Click” analytics for ‘‘click” chemistry – A simple method for calibration–free evaluation of online NMR spectra N2 - Driven mostly by the search for chemical syntheses under biocompatible conditions, so called "click" chemistry rapidly became a growing field of research. The resulting simple one-pot reactions are so far only scarcely accompanied by an adequate optimization via comparably straightforward and robust analysis techniques possessing short set-up times. Here, we report on a fast and reliable calibration-free online NMR monitoring approach for technical mixtures. It combines a versatile fluidic system, continuous-flow measurement of 1H spectra with a time interval of 20 s per spectrum, and a robust, fully automated algorithm to interpret the obtained data. As a proof-of-concept, the thiol-ene coupling between N-boc cysteine methyl ester and allyl alcohol was conducted in a variety of non-deuterated solvents while its time-resolved behaviour was characterized with step tracer experiments. Overlapping signals in online spectra during thiol-ene coupling could be deconvoluted with a spectral model using indirect hard modeling and were subsequently converted to either molar ratios (using a calibrationfree approach) or absolute concentrations (using 1-point calibration). For various solvents the kinetic constant k for pseudo-first order reaction was estimated to be 3.9 h-1 at 25 °C. The obtained results were compared with direct integration of non-overlapping signals and showed good agreement with the implemented mass balance. KW - Online NMR Spectroscopy KW - Reaction Monitoring KW - Automated Data Evaluation KW - Thiol-ene click chemistry KW - Click Chemistry KW - Process Analytical Technology PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-393232 UR - http://www.sciencedirect.com/science/article/pii/S1090780717300575 DO - https://doi.org/10.1016/j.jmr.2017.02.018 VL - 277 SP - 154 EP - 161 PB - Elsevier Inc. CY - Oxford AN - OPUS4-39323 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kern, Simon A1 - Michalik-Onichimowska, Aleksandra A1 - Riedel, Jens A1 - Panne, Ulrich A1 - King, R. A1 - Maiwald, Michael ED - Herwig, Christoph T1 - “Click” analytics for “click” chemistry – a simple method for calibration-free evaluation of online NMR spectra N2 - Currently, research in chemical manufacturing moves towards flexible plug-and-play approaches focusing on modular plants, capable of producing small scales on-demand with short down-times between individual campaigns. This approach allows for efficient use of hardware, a faster optimization of the process conditions, and thus, an accelerated introduction of new products to the market. Driven mostly by the search for chemical syntheses under biocompatible conditions, so-called “click” chemistry rapidly became a growing field of research. The resulting simple one-pot reactions are so far only scarcely accompanied by an adequate optimization via comparably straightforward and robust analysis techniques. Here we report on a fast and reliable calibration-free online high field NMR monitoring approach for technical mixtures. It combines a versatile fluidic system, continuous-flow measurement with a time interval of 20 s per spectrum, and a robust, automated algorithm to interpret the obtained data. All spectra were acquired using a 500 MHz NMR spectrometer (Varian) with a dual band flow probe having a 1/16-inch polymer tubing working as a flow cell. Single scan 1H NMR spectra were recorded with an acquisition time of 5 s, relaxation delay of 15 s. As a proof-of-concept, the thiol-ene coupling between N-boc cysteine methyl ester and allyl alcohol was conducted in non-deuterated solvents while its time-resolved behaviour was characterised with step tracer experiments. Through the application of spectral modeling the signal area for each reactant can be deconvoluted in the online spectra and thus converted to the respective concentrations or molar ratios. The signals which were suitable for direct integration were used herein for comparison purposes of both methods. T2 - 11. Interdisziplinäres Doktorandenseminar CY - Berlin, Germany DA - 12.03.2017 KW - Process Monitoring KW - Online NMR Spectroscopy KW - Indirect Hard Modeling KW - Process Control KW - Process Analytical Technology KW - CONSENS KW - Click Chemistry PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-435531 SP - 33 EP - 35 PB - Gesellschaft Deutscher Chemiker (GDCh) CY - Frankfurt a. M. AN - OPUS4-43553 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Riedel, Jens T1 - Laser-induzierte Plasmaspektroskopie zur Prozessanalytik an Schlacken im elektrischen Lichtbogenofen T2 - ANAKON 2013 CY - Essen, Germany DA - 2013-03-04 PY - 2013 AN - OPUS4-30342 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -