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Peanut hulls (Arachis hypogaea, Leguminosae), which are a side stream of global peanut processing, are rich in bioactive flavonoids such as luteolin, eriodictyol, and 5,7-dihydroxychromone. This study aimed to isolate these flavonoid derivatives by liquid-liquid chromatography with as few steps as possible. To this end, luteolin, eriodictyol and 5,7-dihydroxychromone were isolated from peanut hulls using two different techniques, high-performance countercurrent chromatography (HPCCC) and fast-centrifugal partition chromatography (FCPC). The suitability of the biphasic solvent system composed of n-hexane/ethyl acetate/methanol/water (1.0/1.0/1.0/1.5; v/v/v/v) was determined by the Conductor like Screening Model for Real Solvents (COSMO-RS), which allowed the partition ratio KD-values of the three main flavonoids to be calculated. After a one-step HPCCC separation of ~1000 mg of an ethanolic peanut hull extract, 15 mg of luteolin and 8 mg of eriodictyol were isolated with purities over 96%. Furthermore, 3 mg of 5,7-dihydroxychromone could be isolated after purification by semi-preparative reversed-phase liquid chromatography (semi-prep. HPLC) in purity of over 99%. The compounds were identified by electrospray ionization mass spectrometry (ESI-MS) and nuclear magnetic resonance spectroscopy (NMR).

Herpes simplex virus type 1 (HSV-1) has several therapeutic indications including cancer, dermatological diseases and neurological disorders. For the clinical studies, high 106–108 plaque forming unit per mL (PFU mL-1) formulated virus doses are required. Supplying this amount of virus is challenging since the upstream process titer is influenced by numerous, non-linearly dependent parameters as well as by the genetic nature of the virus. The aim of this work was to characterize and mathematically model the wild-type HSV-1 production process as a basis for producing high quantity and quality virus. Three HSV-1 permissive cell lines (Vero, suspension HEK-293 and BHK-21) were considered for the production. However, due to the superior Vero cell productivity, the process development focused on Vero cells growing on Cytodex 1 microcarrier in a stirred tank bioreactor. Results showed that temperature (33 and 37 °C), pH (6.5–7.4) and medium exchange before time of infection (TOI) are not only factors for improving the virus titer but also the virus quality (ratio of PFU to virus genome copies). For the first time, the HSV-1 production—from cell inoculation until harvest—was described with a mathematical model. This model was used to maximize the virus titer by varying the TOI (2–3.5 days) and multiplicity of infection (MOI) (0.0001–0.1), which was possible without compromising the virus quality. This work revealed that ammonium accumulation in Vero cell cultures inhibits HSV-1 propagation, even more severely in higher cell density cultures. Using pyruvate or GlutaMAX supplementation instead of L-glutamine reduced the ammonium accumulation and increased the virus titer 2.9-fold in high cell density cultures (3.5 x 106 cells mL-1) in shaking flask, respectively. Alternatively, applying a daily medium exchange after TOI in glutamine cultures also led to comparable titers to pyruvate and GlutaMAX cultures. Overall, increasing the cell density from 1.0 x 106 cells mL-1 to 3.7 x 106 cells mL-1 for the TOI increased the titer 1.9-fold and space-time yield 1.6-fold in pyruvate bioreactor cultures. Genetically modified HSV-1 vectors were produced by applying the wild-type HSV-1-based process. While the insertion sites and transgenes (for targeting tumor cells or immune checkpoint inhibitor) into the virus genome decreased the virus titer 2.7–4.5 fold, the production of these viruses was still economically feasible. Yet attenuating the virus (by deletion of UL39 and mutation of UL37 gene) resulted an order of magnitude lower titer than the wild type virus and will require a complementing Vero cell line to achieve economic production titers., Das Herpes-simplex-Virus Typ 1 (HSV-1) hat mehrere therapeutische Indikationen, darunter Krebs, Hautkrankheiten und neurologische Störungen. Für klinische Studien werden hoch formulierte Virusdosen im Bereich von 106 bis 108 Plaque formenden Einheiten per mL (PFU mL-1) benötigt. Die Bereitstellung dieser Virusmenge stellt eine Herausforderung dar, da der Titer des Upstream-Prozesses von zahlreichen, nicht linear abhängigen Parametern, sowie von der genetischen Beschaffenheit des Virus beeinflusst wird. Ziel dieser Arbeit war es, den Wildtyp-HSV-1-Produktionsprozess zu charakterisieren und mathematisch zu modellieren, um eine Grundlage für die Produktion von Viren in hoher Quantität und Qualität zu schaffen. Drei HSV-1-permissive Zelllinien (Vero, HEK-293 und BHK-21) wurden für die Produktion in Betracht gezogen. Aufgrund der überlegenen Produktivität der Vero-Zellen konzentrierte sich die Prozessentwicklung auf Vero-Zellen, die auf Cytodex 1 in einem Rührkessel Bioreaktor gewachsen sind. Die Ergebnisse zeigten, dass sowohl die Wahl der Temperatur (33 und 37 °C) und des pH-Werts (6,5-7,4) als auch der Austausch des Mediums vor dem Infektionszeitpunkt (TOI) den Virustiter und die Virusqualität (Verhältnis von PFU zu Virusgenomkopien) beeinflussen. Zum ersten Mal wurde die HSV-1-Produktion—von der Zellinokulation bis zur Ernte—eines mathematischen Modells beschrieben. Dieses Modell wurde verwendet, um den Virustiter durch Variation der TOI (2-3,5 Tage) und der Multiplizität der Infektion (MOI) (0,0001-0,1) zu maximieren, was ohne Beeinträchtigung der Virusqualität möglich war. Diese Arbeit enthüllte, dass die Anreicherung von Ammonium in Vero-Zellkulturen die Vermehrung von HSV-1 hemmt und dieser Effekt mit erhöhter Zelldichte zunehmend ist. Durch Verwendung von Pyruvat oder GlutaMAX anstelle von L-Glutamin konnte diese Ammoniumakkumulation verringert werden, was zu einem 2,9-fach erhöhten Virustiter in Kulturen mit hoher Zelldichte (3,5 x 106 Zellen mL-1) im Schüttelkolben führte. Alternativ dazu führte ein täglicher Mediumwechsel nach TOI zu vergleichbaren Erträgen mit Glutamin wie unter Verwendung von Pyruvat und GlutaMAX. Insgesamt verbesserte die Erhöhung der Zelldichte von 1,0 x 106 auf 3,7 x 106 Zellen mL-1 den Titer um das 1,9-fache und die Raumzeitausbeute um das 1,6-fache in Pyruvat-Bioreaktorkulturen. Zusätzlich wurden gentechnisch veränderte HSV-1-Vektoren durch Anwendung des Wildtyp-HSV-1-basierten Verfahrens hergestellt. Obwohl die Insertionsstellen und Transgene (für Zielsteuerung auf Tumorzellen oder den Immun-Checkpoint-Inhibitor) den Virustiter um das 2,7- bis 4,5-fache verringerten, war die Herstellung dieser Viren dennoch wirtschaftlich umsetzbar. Eine Abschwächung des Virus (durch Deletion von UL39 und Mutation des UL37-Gens) reduzierte den Titer jedoch um eine Größenordnung gegenüber dem Wildtyp-Virus und erfordert eine komplementäre Vero-Zelllinie, um wirtschaftliche Produktionserträge zu erzielen.

Numerous synthetic techniques for the fabrication of porous metal electrodes were developed in recent decades. A very promising and facile route is the 3D printing of structures, which can be designed directly on the computer first. However, the current techniques allow structures to be printed with a resolution down to 20 µm, which is still quite rough regarding tuning the pore distribution and diameter of electrode materials for potential applications. For the first time, a laser-induced forward transfer (LIFT) process was used to 3D print metal voxels on a solid surface, resulting in a porous electrocatalytically active gold (Au) electrode film. Porous Au electrodes produced using LIFT showed an increase in the electrochemically active surface area (SA) by a factor of four compared with a sputtered dense Au film when characterized using cyclic voltammetry (CV) in Ar-saturated 0.1 M KOH. Therefore, the LIFT process can be considered very promising for the printing of ordered porous electrodes with high surface areas for electrochemical applications.

Insect bite hypersensitivity (IBH) is the most common allergic skin disease of horses. It is caused by insect bites of the Culicoides spp. which mediate a type I/IVb allergy with strong involvement of eosinophil cells. No specific treatment option is available so far. One concept could be the use of a therapeutic antibody targeting equine interleukin 5, the main activator and regulator of eosinophils. Therefore, antibodies were selected by phage display using the naïve human antibody gene libraries HAL9/10, tested in a cellular in vitro inhibition assay and subjected to an in vitro affinity maturation. In total, 28 antibodies were selected by phage display out of which eleven have been found to be inhibiting in the final format as chimeric immunoglobulin G with equine constant domains. The two most promising candidates were further improved by in vitro affinity maturation up to factor 2.5 regarding their binding activity and up to factor 2.0 regarding their inhibition effect. The final antibody named NOL2262D10 showed a strong inhibition of the interleukin 5 binding to its receptor (IC50 = 4 nM). Furthermore, a nanomolar binding activity (EC50 = 8.8 nM), stable behavior and satisfactory producibility were demonstrated. This antibody is an excellent candidate for in vivo studies for the treatment of equine IBH.

Biopharmazeutika werden zur Therapie einer Vielzahl von schwerwiegenden Krankheiten wie Krebs und Autoimmunerkrankungen verwendet. Sie zeichnen sich insbesondere in der Onkologie durch eine im Vergleich zu chemischen Medikamenten deutlich höhere Spezifität und ein reduzierteres Nebenwirkungsspektrum aus. Die Hauptgruppe der Biopharmazeutika sind heutzutage monoklonale Antikörper, die hauptsächlich in CHO-Zellen hergestellt werden. Denn CHO-Zellen besitzen gegenüber anderen Expressionssystemen. einige entscheidende Vorteile für die biopharmazeutische Produktion. Ein stetig wachsender Markt und die steigende Nachfrage zwingen die biopharmazeutische Industrie Zelllinien schneller zu entwickeln und höhere Titer zu erreichen. In dieser Arbeit wurden verschiedene Herangehensweisen verwendet, um die Entwicklung einer CHO-Produktionszelllinie zu optimieren. Es konnte am Beispiel von Antikörpern gezeigt werden, dass die genetische Konfiguration der CHO-Hostzelle einen Einfluss sowohl auf den Titer, als auch auf den Zeitbedarf für die Zelllinienentwicklung hat. Dazu wurden verschiedene molekulare Werkzeuge verwendet, mit denen die Ausbeuten eines full size IgG und eines Antikörperfragments gesteigert werden konnten. Dabei wurden verschiedene Engpässe umgangen, die während der Proteinbiosynthese innerhalb der Zelle auftreten und so die Produktion gesteigert: a) Durch die Optimierung der Transkription mit Hilfe von Signalpeptiden konnte die Quantität des full size Antikörpers um mehr als das Doppelte gesteigert werden. b) Durch den Einsatz eines UCOEs, einem Chromatin modifizierenden Element, das die Zugänglichkeit des Gens für die Transkription verbessert, konnte die Quantität des Antikörperfragments um das 0,7-fache gegenüber einer Referenz ohne UCOE erhöht werden. c) Durch die Überexpression eines Gens, das die Sekretion verbessert, konnte die Quantität des Antikörperfragments um das Vierfache gesteigert werden. Neben der Produktionssteigerung wurde auch die Methodik der Zelllinienentwicklung optimiert. So konnte gezeigt werden, dass ein Screening auf der Ebene von „Minipools“ deutlich mehr Hochproduzenten hervorbrachte, die eine höhere Quantität des full size Antikörpers vorwiesen, als ein einziger „Largepool“. Der Aufwand für das multiparallele Screening auf Hochproduzenten wurde durch die Etablierung eines MicroFlask Systems, mit dem bis zu 24 Pools parallel in kleinem Volumen in einer Platte kultiviert werden können, signifikant verringert. Ein Vergleich zwischen einem klassischen Fed-Batch mit einem vereinfachten Simple-Fed-Batch, bei dem eine Glukoselösung als einzige Nährstoffzugabe hinzugefügt wurde, zeigte, dass mit weniger Aufwand schneller vergleichbare Ergebnisse erzielt werden können., Biopharmaceuticals are used for the treatment of a variety of serious diseases such as cancer and autoimmune diseases. In oncology in particular, they are characterized by significantly higher specificity and reduced side effects compared to chemical drugs. The main group of biopharmaceuticals today are monoclonal antibodies, which are mainly produced in CHO cells. These cells possess some key advantages over other expression systems. For biopharmaceutical production a steadily growing market and increasing demand are forcing the biopharmaceutical industry to develop cell lines faster and achieve higher titres. In this work, different approaches were used to optimize the development of a CHO production cell line. It was shown for antibodies that the genetic configuration of the CHO host cell has an impact on both the titre and the time need for cell line development. For this purpose, different molecular tools were used to increase the yields of a full size IgG and an antibody fragment. Several bottlenecks that occur during protein biosynthesis within the cell were bypassed to increase production: a) By optimizing transcription using signal peptides, the quantity of a full size antibody was increased more than twofold. b) Using a UCOE, a chromatin modifying element that improves the accessibility of the gene for transcription, increased the quantity of the antibody fragment by 0.7-fold compared to a reference without a UCOE. c) Overexpression of a gene that enhances secretion increased the quantity of antibody fragment fourfold. In addition to the increase in production, the methodology of cell line development was also optimized. It was shown that screening at the level of "minipools" yielded significantly more high producers, which had a higher quantity of the full size antibody, than a single "largepool". The effort required for multiparallel screening for high producers was significantly reduced by establishing a MicroFlask system that allows up to 24 pools to be cultured in parallel in small volume in one plate. A comparison between a classical fed-batch with a simplified simple fed-batch, where only a glucose solution serves as nutrition add-on, showed that comparable results can be achieved faster with less effort.

Bernsteinsäure (BS) kann auf biotechnischem Weg aus einer Vielzahl von Substraten mit hohen Ertragskoeffizienten, hoher Produktivität und hohen Endkonzentrationen hergestellt werden. Dabei kann auf das vorherrschende Roh- und Reststoffpotential aus Agrar- und Landwirtschaft zurückgegriffen werden. Die hergestellte BioBernsteinsäure dient dann als Ausgangsstoff für eine Vielzahl an Chemikalien und Polymeren. Biotechnisch hergestellte BS findet außerdem in empfindlichen Bereichen der Lebensmittel-, Pharma- und Kosmetikindustrie zahlreich Verwendung. Dadurch, dass BS ein Zwischenprodukt des Citratzyklus und ein Stoffwechselprodukt einiger Mikroorganismen ist, lässt sich die biotechnische Herstellung mit vergleichsweise einfachen Mitteln umsetzen. Besonders eignen sich hierbei natürliche Überproduzenten, welche BS über den reduktiven Citratzyklus produzieren. Während des reduktiven Citratzyklus wird CO2 eingelagert, wodurch Ertragskoeffizienten von größer 1 gBS/gSubstrat erzielt werden können. Ziel der vorliegenden Arbeit war es, einen biotechnischen Produktionsprozess im Hinblick auf Ertragskoeffizient, Produktivität und Bernsteinsäureendkonzentration zu optimieren. Als Substrat diente Glycerin, welches hauptsächlich bei der Biodieselproduktion als Abfallprodukt entsteht. Im Verlauf dieser Arbeit wurden grundlegende Erkenntnisse zur Bernsteinsäureproduktion mit der unbekannten, aus dem Boden isolierten Mischkultur DSM 32268, welche einen neuartigen Organismus der Actinobacteria enthält, gewonnen. Hierbei gehörte die Einstellung der optimalen Sauerstoff- und auch Kohlenstoffdioxidverfügbarkeit für den mikroaerophilen, sowie kapnophilen Organismus zu den Hauptschwerpunkten. Prozessparameter wie pH-Wert, Temperatur, Redoxpotential, Rührerdrehzahl und Begasungsraten wurden zu diesem Zweck in verschiedenen Reaktorsystemen untersucht. Die besten Ergebnisse wurden im Zulaufverfahren erzielt, bei welchem im vorangestellten Satzbetrieb eine Glycerinanfangskonzentration von 50 g/L eingesetzt wurde und dem System im folgenden Zulauf jeweils ca. 35 g/L reines Glycerin zugegeben wurde. Bei der wachstumsentkoppelten Produktion wurden ein Ertragskoeffizent, eine Produktivität und eine maximale Bernsteinsäureendkonzentration von Y=1,15 g/g, P=0,39 g/(L*h) und BS=117 g/L erreicht. Beim Einsatz von 50 g/L Glycerin wurden im Satzbetrieb ein Ertragskoeffizient, eine Produktivität und eine Bernsteinsäureendkonzentration von Y=0,98 g/g, P=0,55 g/(L*h) und BS=50,8 g/L erhalten. Somit lässt sich der in dieser Arbeit entwickelte Produktionsprozess als konkurrenzfähig einordnen., Succinic acid (SA) can be bioengineered from a variety of substrates with high yield, high productivity, and high final product concentrations. In doing so, the prevailing feedstock and residual material potential from agriculture can be used. The biosuccinic acid produced is then used as basic material for a large number of chemicals and polymers. Biotechnically produced SA is also widely used in sensitive areas of food, drug and cosmetic industries. Since SA is an intermediate of the citric acid cycle and a metabolic product of microorganisms, biotechnical production can be implemented with comparatively simple means. Natural overproducers that produce SA via the reductive citric acid cycle are particularly suitable here. CO2 is stored during the reductive citric acid cycle, which means that yields of more than 1 gSA/gsubstrate can be achieved. The aim of the present work was to optimize a biotechnical production process with regard to yield, productivity and final SA concentration. The used substrate was Glycerol, which mainly occurs as a waste product in biodiesel production. In the course of this work, fundamental insights into SA production were gained with the unknown soil-isolated mixed culture DSM 32268, which contains a novel Actinobacteria organism. The adjustment of the optimal availability of oxygen and carbon dioxide for the microaerophilic and capnophilic organism was one of the main focuses. For this purpose, process parameters such as pH, temperature, redox potential, stirrer speed and gassing rates were investigated in different reactor systems. The best results were achieved by fed-batch process, in which an initial glycerol concentration of 50 g/L was used in the preceding batch operation and approx. 35 g/L of pure glycerine was added to the system in subsequent feed. In growth-decoupled production, yield, productivity and maximum final SA concentration of Y=1.15 g/g, P=0.39 g/(L*h), SA=117 g/L were achieved. When using 50 g/L glycerol inital during batch, yield , productivity and final SA concentration of Y=0.98 g/g, P=0.55 g/(L*h), SA=50.8 g/L were achieved. Thus, the production process developed in this work can be classified as competitive.

High-performance countercurrent chromatography (HPCCC) was used for the target-guided isolation of precursors of 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN) from Riesling wine. In separated HPCCC fractions of an Amberlite® XAD®-2 extract obtained from a German Riesling, TDN-generating fractions were identified by the acid-catalyzed hydrolysis of the progenitors at pH 3.0 and subsequent HS-GC-MS/MS analysis. The presence of multiple TDN-generating precursors in Riesling wine could be confirmed. From polar HPCCC fractions (11–13 and 14–16), 3,4-dihydroxy-7,8-dihydro-β-ionone 3-O-rutinoside and 3,4-dihydroxy-7,8-dihydro-β-ionone 3-O-β-d-glucopyranoside were isolated as major TDN-precursors at a sufficient amount for structure elucidation by NMR spectroscopic studies. In the medium polar HPCCC factions (27–35), enzymatic hydrolysis liberated the aglycones 3-hydroxy-β-ionone and 3-hydroxy-TDN in minor amounts. In further less polar TDN-generation fractions (36–44 and 45–50), glycosidic progenitors were absent; instead, a minor TDN formation most likely from non-conjugated constituents was observed.

Microbioreactors (MBRs) with a volume below 1 mL are promising alternatives to established cultivation platforms such as shake flasks, lab-scale bioreactors and microtiter plates. Their main advantages are simple automatization and parallelization and the saving of expensive media components and test substances. These advantages are particularly pronounced in small-scale MBRs with a volume below 10 µL. However, most described small-scale MBRs are lacking in process information from integrated sensors due to limited space and sensor technology. Therefore, a novel capillary-wave microbioreactor (cwMBR) with a volume of only 7 µL has the potential to close this gap, as it combines a small volume with integrated sensors for biomass, pH, dissolved oxygen (DO) and glucose concentration. In the cwMBR, pH and DO are measured by established luminescent optical sensors on the bottom of the cwMBR. The novel glucose sensor is based on a modified oxygen sensor, which measures the oxygen uptake of glucose oxidase (GOx) in the presence of glucose up to a concentration of 15 mM. Furthermore, absorbance measurement allows biomass determination. The optical sensors enabled the characterization of an Escherichia coli batch cultivation over 8 h in the cwMBR as proof of concept for further bioprocesses. Hence, the cwMBR with integrated optical sensors has the potential for a wide range of microscale bioprocesses, including cell-based assays, screening applications and process development.

Previously, different Hydrangea macrophylla ssp. serrata cultivars were investigated by untargeted LC-MS analysis. From this, a list of tentatively identified and unknown compounds that differ significantly between these cultivars was obtained. Due to the lack of reference compounds, especially for dihydro-isocoumarins, we aimed to isolate and structurally characterise these compounds from the cultivar ‘Yae-no-amacha’ using NMR and LC-MS methods. For purification and isolation, counter-current chromatography was used in combination with reversed-phase preparative HPLC as an orthogonal and enhanced purification workflow. Thirteen dihydro-isocoumarins in combination with other metabolites could be isolated and structurally identified. Particularly interesting was the clarification of dihydrostilbenoid glycosides, which were described for the first time in H. macrophylla ssp. serrata. These results will help us in further studies on the biological interpretation of our data.

This study presents a new approach for the recycling of bilayered PET waste in an efficient, continuous process with a depolymerization degree >97%. The complex PET waste was converted by chemolysis into its monomers ethylene glycol (EG) and the corresponding salt of terephthalic acid (TA) in a twin-screw extruder (TSE). Via this method, the starting materials for PET production were recovered, and highly contaminated PET waste and PET composite materials were transformed into valuable starting materials. The PE layer of the composite PET/PE material remained inert under depolymerization conditions and could be separated by filtration. An increase in the rotational speed by 200 rpm in the TSE reduced the residence time, but the degree of depolymerization was not affected in a proportional manner. Thus, the results indicate that a shorter residence time can be compensated with intensified mechanical agitation due to higher rotational speeds to obtain a similar degree of depolymerization. These results support the potential of this recycling concept to substantially contribute to the implementation of a circular PET economy.

Steigende Kundenanforderungen führen zu einer zunehmend vielseitigen Produktgestaltung. Die einzelnen Produktbauteile müssen diesen ständig wachsenden Anforderungen gerecht werden und gewinnen daher an Komplexität. Der Einsatz multimaterieller Bauteile, die beispielsweise aus faserverstärkten Kunststoffen bestehen, verspricht, hohe mechanische Anforderungen bei gleichzeitiger Gewichtsreduktion zu erfüllen. Ein solcher multimaterieller Aufbau führt jedoch zu steigenden Material- und Produktionskosten, weshalb der Vermeidung von Ausschuss eine hohe Bedeutung zukommt. Damit ist der vermehrte Einsatz von zerstörungsfreien und produktionsbegleitenden Prüfverfahren zur Sicherung der Bauteilqualität erforderlich. Mit der Luftultraschalluntersuchung in Transmission hat sich in den letzten Jahren ein zerstörungsfreies Prüfverfahren entwickelt, das in der industriellen Anwendung zunehmend zur Prüfung von multimateriellen Bauteilen mit geometrisch komplexer Formgebung eingesetzt wird. Die Prüfköpfe arbeiten kontaktlos und der Auftrag eines Koppelmediums entfällt. Das Messsignal der Luftultraschalluntersuchung in Transmission weist jedoch starke Abhängigkeiten von der Bauteilgeometrie, den Materialparametern und eventuell auftretenden Fehlerstellen auf. Die Beeinflussung des Messsignals durch die Bauteilgeometrie und die Materialparameter kann über den Einbezug von Konstruktions- und Simulationsdaten prognostiziert und kompensiert werden, sodass dadurch tatsächliche Fehlerstellen durch die Veränderung des Messsignals eindeutig identifizierbar werden. Der Grad der Messsignalbeeinflussung durch die Bauteilgeometrie und die Materialparameter ist für multimaterielle Bauteile jedoch nur aufwendig zu ermitteln und insbesondere für faserverstärkte Kunststoffe bislang nicht bekannt. Deshalb ist die Luftultraschalluntersuchung zur produktionsbegleitenden Qualitätssicherung bislang nicht mit ausreichender Güte einsetzbar. Die vorliegende Arbeit verfolgt das Ziel, durch einen mathematischen Ansatz das Messsignal anhand der gegebenen Bauteilgeometrie und Materialparameter zu prognostizieren. Die Schaffung eines systemischen Verständnisses für das Prüfverfahren an sich sowie für die Wechselwirkungen und Phänomene im Bauteil während der Prüfung trägt wesentlich zur Zielerreichung bei. Dazu werden fehlerfreie Prüfkörper mit variierten Geometrien und Materialparametern aufgebaut und analysiert. Die aus experimentellen Messungen erhaltenen Ergebnisse validieren den in dieser Arbeit entwickelten mathematischen Ansatz. Es wird gezeigt, dass veränderte geometrische Ausprägungen sowie Variationen in den Materialparametern von faserverstärkten Kunststoffen mithilfe des mathematischen Ansatzes abgebildet werden können., Rising customer requirements lead to an increasingly varied product design. The individual components must meet the constantly growing requirements and are therefore becoming increasingly complex. The use of multi-material components, for example made of fiber-reinforced plastics, promises to meet high mechanical requirements while keeping weight down. However, the multi-material structure leads to increasing material and production costs, which is why the prevention of rejects is of major importance. This development demands an increased use of non-destructive and in-process testing methods to ensure component quality. With the air ultrasound examination in transmission, a non-destructive testing method has developed in the past years, which is increasingly used in industrial applications for testing multi-material components with geometrically complex shapes. The probes operate without contact and the application of a coupling medium is not necessary. The measuring signal of the air ultrasonic examination in transmission shows strong dependencies on the component geometry, the material parameters and occurring defects. The influence of the component geometry and the material parameters on the measurement signal can be predicted and compensated for by including design and simulation data, so that actual defects can be clearly identified by the change in the measurement signal. However, the degree of influence of the measurement signal by the component geometry and the material parameters is difficult to determine for multi-material components and, in particular, is not yet known for fiber-reinforced plastics, which is why air ultrasonic examination cannot yet be used with sufficient quality for in-process quality assurance. Against this background, the present work aims to use a mathematical approach to predict the measurement signal based on the given component geometry and material parameters. The creation of a systemic understanding for the test procedure itself as well as the interactions and phenomena in the component during the test contribute significantly to the achievement of the objective. For this purpose, defect-free test specimens with varied geometries and material parameters are built and analyzed. The results obtained from experimental measurements validate the mathematical approach developed in this thesis. It is shown that modified geometric specifications as well as variations in the material parameters of fiber-reinforced plastics can be reproduced using the mathematical approach., Schriftenreihe des Instituts für Werkzeugmaschinen und Fertigungstechnik, vol. 2022

Bei der Steigerung der Leistungsfähigkeit und Sicherheit von Lithium-Ionen-Batterien (LIBs) stellt insbesondere der Eintrag von Wasser während der Produktion eine große Herausforderung dar. Zu hohe Restfeuchten in LIB-Zellen können zu drastisch eingeschränkter elektrochemischer Performance führen und bergen ein großes Sicherheitsrisiko, weshalb die Zellkomponenten vor dem Zellbau nachgetrocknet werden müssen. Obwohl die Nachtrocknung sehr energieaufwändig ist und einen großen Einfluss auf die Produktqualität hat, ist sie nach wie vor nicht im Detail erforscht und verstanden. Die vorliegende Arbeit hat deshalb ein besseres Verständnis und die Optimierung des Vakuum-Nachtrocknungsprozesses von LIB-Elektroden sowie die Erforschung des Wassersorptionsverhaltens der Elektroden zum Ziel. Für ein tiefgehendes Prozessverständnis muss die Prozesstechnik über die mikroskopische Elektrodenstruktur mit den makroskopischen Elektrodeneigenschaften korreliert werden. Die im Rahmen dieser Arbeit durchgeführten Untersuchungen basieren deshalb auf dem Konzept der Prozess-Struktur-Eigenschafts-Beziehungen. Die Ergebnisse zeigen, dass hohe Nachtrocknungsintensitäten zwar einerseits niedrige Restfeuchtegehalte erzielen, andererseits aber die Mikrostruktur der Elektroden und ihre mechanischen, elektrischen und elektrochemischen Funktionseigenschaften schädigen können. Die elektrochemische Performance wird also nicht nur durch den Restfeuchtegehalt, sondern ebenfalls signifikant durch die Nachtrocknungsintensität beeinflusst. Aufbauend auf den identifizierten Prozess-Struktur-Eigenschafts-Beziehungen wird ein allgemeines Verständnis für den Prozess der Vakuum-Nachtrocknung ganzer Elektrodencoils erarbeitet und eine vergleichsweise moderate II-Phasen-Vakuum-Nachtrocknungsprozedur konzipiert und erfolgreich praktisch angewandt. Für ein besseres Verständnis des Sorptionsverhaltens von LIB-Elektroden werden zudem der Einfluss der Mikrostruktur, des Aktivmaterials und des Taupunkts beim Zellbau auf die Wassersorption untersucht und daraus Prozess-Struktur-(Eigenschafts-)Beziehungen abgeleitet. Die im Rahmen dieser Arbeit identifizierten Prozess-Struktur-(Eigenschafts-)Beziehungen bei der Nachtrocknung und dem Wassersorptionsverhalten von LIBs tragen maßgeblich zu einem besseren Prozessverständnis bei. Sie bilden die Grundlage für eine wissensbasierte Auslegung des Nachtrocknungsprozesses sowie des Feuchtemanagements über die gesamte Prozesskette und leisten somit einen wesentlichen Beitrag zur Energie- und Kosteneinsparung sowie Steigerung der Produktqualität und -sicherheit von LIBs., In order to increase the performance and safety of lithium-ion batteries (LIBs), the introduction of water during production, in particular, poses a major challenge. Excessive residual moisture in LIB cells can lead to drastically reduced electrochemical performance and represents a high safety risk. Therefore, the cell components must be post-dried prior to cell assembly. Although post-drying is energy-intensive and has a major impact on the product quality, it is still not well-researched and understood in detail. Therefore, the work presented here aims at better understanding and optimizing the vacuum post-drying process of LIB electrodes, as well as investigating the water sorption behavior of the electrodes. For better process understanding, the process technology must be linked with the microscopic electrode properties through the macroscopic electrode structure. The investigations carried out in this work are therefore based on the concept of process-structure-property relationships. The results show that although high post-drying intensities achieve low residual moisture contents on the one hand, they can damage the microstructure of the electrodes and their mechanical, electrical and electrochemical functional properties on the other hand. The electrochemical performance is therefore not only influenced by the residual moisture content, but also significantly by the post-drying intensity. Based on the identified process-structure-property relationships, a general understanding of the vacuum post-drying of whole electrode coils is developed. A comparatively moderate II-phase vacuum post-drying procedure is designed and successfully applied in practice. For a better understanding of the sorption behavior of LIB electrodes, the influence of the microstructure, the active material and the dew point during cell assembly on water sorption is investigated, and process-structure(-property) relationships are derived. The process-structure(-property) relationships generated in this work, with regard to post-drying and the water sorption behavior of LIBs, contribute significantly to a better process understanding. They form the basis for the knowledge-based design of the post-drying process and the moisture management throughout the entire process chain, and thus make a significant contribution to saving energy and costs and to increasing the product quality and safety of LIBs., Dissertationen der iPAT-Schriftenreihe, vol. 54

The most severe limitations of lithium-sulfur batteries on a cell level are linked to the reaction mechanism, which therefore represents a key feature of knowledge driven development. This study applies a complementary set of chemical and electrochemical characterization methods, including cyclic voltammetry, HPLC and galvanostatic discharge and computational simulation of cyclic voltammetry, to examine the reaction kinetics of sulfur reduction in detail. Cyclic voltammetry in combination with galvanostatic discharge and open circuit potential measurement reveals the electron transfer and chemical reactions at different states of charge, HPLC/MS determines dissolved sulfur quantitatively and dissolved polysulfides qualitatively in the electrolyte during the discharge processes. An E3C4-mechanism is proposed as reaction mechanism, based on the results of the conducted experiments and literature findings. The mechanism is able to reproduce the current signal of cyclic voltammetry experiments, showing all important characteristics. Besides the electrochemical reduction reactions of S8 and S8^2- during the higher voltage discharge plateau and the S4^2- reduction during the lower voltage discharge plateau, circular routes by chemical reactions, that support a deeper discharge of the cell by producing S8 and S4^2-, are proven. The chemical reactions are also balanced to match the HPLC results, which revealed that short chain polysulfides, S3^2- and S4^2-, are favored. Although, sulfur is still present in bulk during the lower voltage discharge plateau, it is chemically converted to S4^2- before reaching the electrode/electrolyte interface. Cycling experiments of lithium-sulfur coin cells uncovered the current dependency of the higher and lower voltage discharge plateau. It can be explained by the circular routes of the mechanism since the conversion reaction is time dependent and therefore significantly influenced by the applied current. This work gives detailed information about the proposed mechanism that enables improved analysis of the shuttle mechanism, Li2S precipitation or overall cell performance. The proposed mechanism represents a great advance in the development of lithium-sulfur batteries by implementing a physically correct view in the interpretation of experimental results and modeling., Die maßgeblichen Limitierungen der Lithium-Schwefel Batterie sind alle verbunden mit dem Reaktionsmechanismus von Schwefel, welcher daher ein wichtigen Baustein zur wissensbasierten Weiterentwicklung der Technologie darstellt. In dieser Arbeit wurden sich ergänzende Methoden der elektrochemischen und chemischen Analyse verwendet, um die Reaktionskinetik von Schwefel im Detail zu analysieren. Diese umfassen Cyclovoltammetrie, HPLC und galvanostatische Entladung und wurden durch die Simulation von Cyclovoltammetrieexperimenten im zuvor implementierten Modell ergänzt. Cyclovoltammetrie in Verbindung mit galvanostatischer Entladung und der Messung der Leerlaufspannung machten die elektrochemischen und chemischen Reaktionen bei verschiedenen Entladezuständen der Zelle sichtbar. Mittels HPLC/MS ließ sich die Konzentration von Schwefel im Entladeverlauf quantitativ bestimmen, die Konzentrationsverläufe der Polysulfide über die Entladung konnten qualitativ bestimmt werden. Basierend auf diesen Ergebnissen und den Erkenntnissen der Literatur wird ein E3C4-Mechanismus empfohlen. Die Simulation mit diesem Mechanismus zeigt übereinstimmende Ströme im Cyclovoltammogram mit den Experimenten. Alle charakteristischen Merkmale im Kurvenverlauf werden reproduziert. Neben den bekannten elektrochemischen Reduktionen von S8 und S8^2- auf dem oberen Spannungsplateau der Entladekurve und der Reduktion von S4^2- auf dem unteren Spannungsplateau der Entladekurve, konnten zyklische Routen belegt werden, welche S8 und S4^2- reproduzieren und eine tiefere Entladung unterstützen. Das Gleichgewicht der chemischen Reaktionen wurde so gewählt, dass die HPLC Ergebnisse, welche S3^2- und S4^2- als primäre Produkte zeigen, berücksichtigt wurden. Obwohl S8 im Elektrolyt auch während des unteren Spannungsplateaus vorhanden ist, erreicht es durch eine Umwandlung zu S4^2- nicht mehr die Elektrodenoberfläche. Es reagiert daher chemisch und nicht mehr elektrochemisch. Diese Arbeit stellt detaillierte Informationen über den empfohlenen Reaktionsmechanismus bereit. Analysen des Shuttle-Mechanismus, des Ausfallens von Li2S oder der Gesamtperformance der Zellen profitieren von der detaillierten Abbildung der inneren Abläufe. Der empfohlene Reaktionsmechanismus repräsentiert daher einen großen Schritt für die Entwicklung von Lithium-Schwefel Batterien, indem er physikalisch korrekte Einblicke in die Interpretation experimenteller Ergebnisse und die Modellierung gewährt.

Generation of sequence defined antibodies from universal libraries by phage display has been established over the past three decades as a robust method to cope with the increasing market demand in therapy, diagnostics and research. For applications requiring the bivalent antigen binding and an Fc part for detection, phage display generated single chain Fv (scFv) antibody fragments can rapidly be genetically fused to the Fc moiety of an IgG for the production in eukaryotic cells of antibodies with IgG-like properties. In contrast to conversion of scFv into IgG format, the conversion to scFv-Fc requires only a single cloning step, and provides significantly higher yields in transient cell culture production than IgG. ScFv-Fcs can be effective as neutralizing antibodiesin vivoagainst a panel of pathogens and toxins. However, different scFv fragments are more heterologous in respect of stability than Fab fragments. While some scFv fragments can be made extremely stable, this may change due to few mutations, and is not predictable from the sequence of a newly selected antibody. To mitigate the necessity to assess the stability for every scFv-Fc antibody, we developed a generic lyophilization protocol to improve their shelf life. We compared long-term stability and binding activity of phage display-derived antibodies in the scFv-Fc and IgG format, either stored in liquid or lyophilized state. Conversion of scFv-Fcs into the full IgG format reduced protein degradation and aggregation, but in some cases compromised binding activity. Comparably to IgG conversion, lyophilization of scFv-Fc resulted in the preservation of the antibodies’ initial properties after storage, without any drop in affinity for any of the tested antibody clones.

An optimization of the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and hydroxy benzotriazole mediated conjugation of the polysaccharide chitosan with functional carboxylic acids was shown. Optimal parameters that enable resource-efficient synthesis of highly functionalized chitosan were identified. In particular, use of only catalytic instead of stoichiometric amounts of hydroxy benzotriazole and tight control of pH in reaction mixture resulted in highly efficient incorporation of the desired moieties as side chains in chitosan. As a result, the model reactant 4-azidobenzoic acid was incorporated resulting in a degree of substitution of over 30% with very high coupling efficacy of up to 90%. Similar results were obtained with other carboxylic acids such as methacrylic acid, 3-(2-furyl) propionic acid and 3-maleimido propionic acid, highlighting the broad applicability of our findings for the functionalization of chitosan.

Multi-step cascade reactions have gained increasing attention in the biocatalysis field in recent years. In particular, multi-enzymatic cascades can achieve high molecular complexity without workup of reaction intermediates thanks to the enzymes’ intrinsic selectivity, and where enzymes fall short, organo- or metal catalysts can further expand the range of possible synthetic routes. Here, we present two enantiocomplementary (chemo)-enzymatic cascades composed of either a styrene monooxygenase (StyAB) or the Shi epoxidation catalyst for enantioselective alkene epoxidation in the first step, coupled with a halohydrin dehalogenase (HHDH)-catalysed regioselective epoxide ring opening in the second step for the synthesis of chiral aliphatic non-terminal azidoalcohols. Through the controlled formation of two new stereocenters, corresponding azidoalcohol products could be obtained with high regioselectivity and excellent enantioselectivity (99% ee) in the StyAB-HHDH cascade, while product enantiomeric excesses in the Shi-HHDH cascade ranged between 56 and 61%.

The need for energy-storing technologies with lower environmental impact than Li-ion batteries but similar power metrics has revived research in Zn-based battery chemistries. The application of bio-based materials as a replacement for current components can additionally contribute to an improved sustainability of Zn battery systems. For that reason, bacterial cellulose (BC) was investigated as separator material in Ni-Zn batteries. Following the biotechnological production of BC, the biopolymer was purified, and differently shaped separators were generated while surveying the alterations of its crystalline structure via X-ray diffraction measurements during the whole manufacturing process. A decrease in crystallinity and a partial change of the BC crystal allomorph type Iα to II was determined upon soaking in electrolyte. Electrolyte uptake was found to be accompanied by dimensional shrinkage and swelling, which was associated with partial decrystallization and hydration of the amorphous content. The separator selectivity for hydroxide and zincate ions was higher for BC-based separators compared to commercial glass-fiber (GF) or polyolefin separators as estimated from the obtained diffusion coefficients. Electrochemical cycling showed good C-rate capability of cells based on BC and GF separators, whereas cell aging was pronounced in both cases due to Zn migration and anode passivation. Lower electrolyte retention was concluded as major reason for faster capacity fading due to zincate supersaturation within the BC separator. However, combining a dense BC separator with low zincate permeability with a porous one as electrolyte reservoir reduced ZnO accumulation within the separator and improved cycling stability, hence showing potentials for separator adjustment.

Es wurden Copolymere synthetisiert und als Beschichtung auf Edelstahl und Kupfer - als Materialien mit deutlich höherer Leitfähigkeit als Grafit - aufgetragen, analysiert und auf Eignung als Anodenmaterial in mikrobiellen Brennstoffzellen untersucht. Die bisher mit purem Kupfer und Edelstahl erreichten ausbaufähigen Leistungen der reinen Materialien sind dabei besonders bei Edelstahl sollten durch Copolymere mit Komponenten zur Anbindung, zur Förderung der bakteriellen Adhäsion sowie zur Verbesserung des Elektronentransfers verbessert werden. Zur Anbindung auf Edelstahl wurden zwei chemisorbierende Phosphonate und eine Phosphonsäure mit quartären Ammoniumsalzen als zweite Komponente gewählt, da diese als wachstumsfördernd bei anodophilen Bakterien gelten. Die Beschichtung erfolgte mittels Spray-Coating und wurde mit Ellipsometrie, Kontaktwinkel und elektrochemischer Methoden analysiert. Hierbei lösten sich die phosphonathaltigen Beschichtungen bei Potentialen unter -0,2 V vs. Ag/AgCl. Die Verwendung der redoxaktiven Gruppe TEMPO verhinderte zwar das Ablösen der Schichten, allerdings verhinderte die TEMPO-Gruppe das Anwachstum der Bakterien. Zur Anbindung auf Kupfer sind schwefelhaltige Komponenten zur Physi- bzw. Chemisorption nötig. Als zweite Komponente wurde das quartäre Ammoniumsalz bzw. die redoxaktive Gruppe Ferrocen verwendet und mittels eines simplen Tauchprozesses beschichtet. Dieser musste anaerob erfolgen, da ansonsten abhängig vom Polymer verschiedene Oxidschichten generiert wurden. Die dünne Oxidschicht verschob die Oxidation des Kupfers zu höheren Potentialen im Vergleich zu reinem Kupfer, während die Leistungsfähigkeit als Anodenmaterial für alle Materialien vergleichbar. Die thiolhaltigen Polymeren nicht erfolgreich auf Kupfer aufgebracht werden. Zuletzt wurde die Autopolymerisation Dopamin und dessen Copolymerisation mit 1,1‘-Ferrocendicarboxaldehyd zur Modifikation von Oberflächen in Bezug auf das Schichtwachszum, die Oberflächentopografie und die elektrochemischen Eigenschaften untersucht, wobei das Copoolymer zu schneller wachsenden und homogeneren Schichten führte. Beide Beschichtungen verschoben die Oxidation des Kupfers zu höheren Potentialen. Die Leistung als Anodenmaterial war für beide Beschichtungen höher als bei reinem Kupfer. Die Anwachszeit war allerdings bei der reinen Polydopaminbeschichtung deutlich kürzer als beim modifizierten Polydopamin, was die Polydopaminbeschichtung als geeignetstes Material ausweist., Copolymers have been synthesized for the coating of stainless steel (SS) and copper since their electric conductivity is better than for graphite. The copolymer coatings with components to bind on the surface, fasten up the initial adhesion of the bacteria and enhance the charge transfer were synthesized, coated, and analysed anode material in microbial fuel cells (MFCs) to improve their power especially for SS. Due to chemisorption two phosphonates and one phosphonic acid has been used on SS with quaternary ammonia salts as second component to improve the growth of anodophilic bacteria. The copolymers were analysed due to their r-parameters by NMR-spectroscopy and their coating behaviour via spray-coating by ellipsometry, contact angle and electrochemical methods. It was observed that the phosphonatic layers detached below -0.2 V vs. Ag/AgCl. The phosphonic acid layers stayed stable, but the current densities in the chronoamperometric measurements remain low. The redox active component TEMPO prevented a detachment. However, the TEMPO moiety was antimicrobial. Sulphur containing moieties were investigated for the binding on copper since sulphur due to physisorbation or chemisorbation with quaternary ammonia salts or the redox active group ferrocene as second component. Again r-parameters were determined for each couple. The coating was done by a dipping process. However, only different oxide layers were built depending from the utilized copolymer if not worked under nitrogen. The thin oxide layers shifted the oxidation of the bulk material to higher potentials compared to pure copper, whereas the powers of the different copper materials were comparable. The polymers containing thiols could not be coated successful. The auto polymerization of dopamine and its copolymerization with 1,1’- ferrocenedicarboxaldehyd are further possible modifications of surfaces. The growth of the different coatings and the coatings themselves have been investigated. A faster growth was observed for the ferrocene containing polydopamine. Furthermore the coatings differ in their surface topography. Both coatings shift the oxidation of the copper to higher potentials. The power of the coatings as anode material was higher than the pure copper. However, the start- up time of the ferrocene modified dopamine was higher than the dopamine coated or the uncoated copper. As conclusion polydopamine coated copper is an effective anode material in MFCs.

In the present study, it is shown that the concentration dependency of undefined mixed culture anodic biofilms does not follow a single kinetic curve, such as the Nernst-Monod curve. The biofilms adapt to concentration changes, which inevitably have to be applied to record kinetic curves, resulting in strong shifts of the kinetic parameters. The substrate concentration in a continuously operated bioelectrochemical system was changed rapidly via acetate pulses to record Nernst-Monod curves which are not influenced by biofilm adaptation processes. The values of the maximum current density jmax and apparent half-saturation rate constant Ks increased from 0.5 to 1 mA cm−2 and from 0.5 to 1.6 mmol L−1, respectively, within approximately 5 h. Double pulse experiments with a starvation phase between the two acetate pulses showed that jmax and Ks decrease reversibly through an adaptation process when no acetate is available. Pseudo-capacitive charge values estimated from non-turnover cyclic voltammograms (CV) led to the hypothesis that biofilm adaptation and the observed shift of the Nernst-Monod curves occurred due to changes in the concentration of active redox proteins in the biofilm. It is argued that concentration-related parameters of kinetic models for electroactive biofilms are only valid for the operating points where they have been determined and should always be reported with those conditions.

Das Ziel dieser Arbeit ist die Synthese von Glycoprotein-Analoga zur Modifizierung von Titan-Oxidoberflächen basierend auf einem Polypeptid-Rückgrat, das Phosphonat- und Kohlenhydrat-Seitengruppen trägt. Außerdem soll der Einfluss der Sekundärstruktur auf die Beschichtungen untersucht werden. Zur Synthese von Polypeptiden mit Phosphonat- und Kohlenhydrat-Seitengruppen wurde als Rückgrat Poly(alpha,L-glutaminsäure) verwendet. Der Einsatz verschiedener Initiatorsysteme ermöglichte die Darstellung von Polypeptiden mit variierbarem Polymerisationsgrad. Anschließend wurden polymeranalog die verschiedenen Seitenketten mit dem Kupplungsreagenz 4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinchlorid (DMT-MM) an das Rückgrat angebunden. Die Beschichtung von Titanoxid-Oberflächen mit den Polypeptiden, die Phosphonat-Seitengruppen tragen, konnte erfolgreich durchgeführt werden, was über Ellipsometrie, Kontaktwinkel-, XPS- und RAIRS-Messungen nachgewiesen wurde. Die spektroskopischen Untersuchungen der Polypeptide vor der Beschichtung, d.h. in Lösung, und nach der Anbindung belegen eine Konformationsänderung von einer ungeordneten bis schwach helicalen zu einer geordneten, helicalen Struktur. Diese Konformationsänderung findet wahrscheinlich während des Temperatur-induzierten Anbindungsschritts statt. Wenn Phosphonat- und Kohlenhydrat-Seitenketten im Polypeptid vorhanden sind, sinkt die Schickdicke in Abhängigkeit von der Zuckerdichte. Die Polypeptide konnten in Abhängigkeit von der Phosphonat-Seitenkette, des Polymerisationsgrads und des Substitutionsgrads auf ihre Sekundärstruktur in Lösung untersucht werden. Ist als Seitenkette ein Phosphonatester am Rückgrat angebunden, dann ist bei niedrigen bis mittleren Substitutionsgraden ein Helix-Knäuel-Übergang zu beobachten und im sauren pH-Bereich eine vollständige helicale Anordnung möglich. Bei höheren Substitutionsgraden ist dieser Übergang nur sehr schwach oder gar nicht vorhanden. Nimmt die Hydrophilie der Seitenkette aufgrund chemischer Modifikationen zu, sinkt der helicale Anteil im Polypeptid, da die Wechselwirkungen der Seitenketten mit dem Rückgrat sowie der Solvatationseffekt wegen der höheren Polarität zunehmen. Grundsätzlich liegen die Polypeptide im neutralen pH-Bereich als ungeordnetes Zufallsknäuel vor, was dafür spricht, dass die helicale Konformation der Polypeptide, die nach der Anbindung auf Titanoxid-Oberflächen nachgewiesen werden konnte, während des Temper-Schritts der Anbindung stattfindet., The aim of this work is the synthesis of glycoprotein analogues for the modification of titanium oxide surfaces based on a polypeptide backbone carrying phosphonate and carbohydrate side chains. Furthermore the influence of the secondary structure on the coatings should be investigated. For the synthesis of polypeptides with phosphonate and carbohydrate side groups, poly (alpha, L-glutamic acid) was used as the polypeptide backbone. The use of different initiator systems allowed the preparation of polypeptides with variable degree of polymerization. Subsequently, the different side chains were attached to the polypeptide backbone via polymer analogous reaction with the coupling reagent 4- (4,6-dimethoxy-1,3,5-triazin-2-yl) -4-methylmorpholine chloride (DMT-MM). The coating of titanium oxide surfaces with the synthesized polypeptides was successful, as evidenced by ellipsometry, contact angle, XPS, and RAIRS measurements. The spectroscopic studies of the polypeptides before coating, in solution, and after binding, show a conformational change from a disordered and accordingly weakly helical to an ordered, helical structure. This conformational change is likely to occur during the temperature-induced binding step. When phosphonate and carbohydrate side chains are present in the polypeptide, the layer thickness of the coatings decreases, depending on the sugar density. The synthesized polypeptides were tested in solution depending on the phosphonate side chain, the degree of polymerization and the degree of substitution on their secondary structure. If a phosphonate ester is attached to the polypeptide backbone, a helix-coil transition can be observed at low to medium degrees of substitution and a complete helical arrangement is possible in the acidic pH range. At higher degrees of substitution this transition is very weak or absent. If the side chain hydrophilicity increases due to chemical modifications, the helical content in the polypeptide decreases as the side chain interactions with the backbone and the solvation effect increase because of the higher polarity. In principle, the polypeptides are present in the neutral pH range as a disordered random coil, which indicates that the helical conformation of the polypeptides, which could be detected after binding to titanium oxide surfaces, takes place during the temperature-induced binding step.

Ziel der Dissertation war die Entwicklung von Itaconsäurederivaten und Verwendung dieser bei der Herstellung von ungesättigten Polyester(UP)-Harzen zur Erweiterung der Einsatzmöglichkeiten. Eine Anwendung von Itaconsäurepolyestern im Topcoatbereich sollte somit ermöglicht werden. Ein Kriterium für den Einsatz von UP-Harzen als Topcoat ist die Flexibilität. Die partielle Substitution von Itaconsäure durch Methylbernsteinsäure führt zur Verringerung der Quervernetzungsdichte und ermöglicht somit eine größere Flexibilität des entstehenden Duromers. Ein weiteres Ziel war die Substitution von Styrol durch biobasierte Reaktivverdünner. Hierfür wurden Dialkylitaconate der Itaconsäure als Reaktivverdünner untersucht. Für die katalytische Hydrierung von Itaconsäure zu Methylbernsteinsäure wurden diverse geträgerte Metallkatalysatoren entwickelt. Diese konnten durch einfache Methoden reproduzierbar hergestellt und erfolgreich in der Hydrierung von Itaconsäure angewendet werden. Die höchste Aktivität wurde für den Bimetallträgerkatalysator 5 % Pd-Pt/SiO2 (Sipernat 22) mit 2800 g Itaconsäure / (h ∙ g Metall) bei einem Wasserstoffdruck von 5 bar, einer Eduktkonzentration von 50 g/L Itaconsäure und einem Reaktionsvolumen von 1 L erreicht. Die Stabilität des Katalysators wurde über fünf Hydrierungsversuche untersucht und zeigte eine stabile Aktivität. Durch einen unkomplizierten Prozess der Hydrierung von Itaconsäure sowie die einfache Polykondensation von Itaconsäure-Methylbernsteinsäure-Gemischen mit 1,3-Propandiol konnten Polyesterharze auf Basis von nachwachsenden Rohstoffen hergestellt werden. Die Anwendung von Itaconsäurederivaten als Reaktivverdünner konnte zudem als Alternative von Styrol-basierten Reaktivverdünnern angewendet werden. Durch Variation der Itaconsäuregehalte in den Polyesterharzen und Veränderung des Reaktivverdünners konnte gezeigt werden, dass die Eigenschaften der gehärteten Polyesterharze durch den Methylbernsteinsäuregehalt und die Wahl des Reaktivverdünners in ihrer Flexibilität und in den mechanischen Eigenschaften beeinflusst werden können. Dies ermöglicht Verwendungen als Laminierharz für faserverstärkte Formteile oder als Polyesterharz für Topcoatanwendungen. Itaconsäurederivate können Styrol in UP-Harzen und in Topcoatanwendungen ersetzen und erreichen ähnliche mechanische Eigenschaften. Die Produkte sind nahezu vollständig biobasiert und erfüllen die steigende Nachfrage nach biobasierten Polyesterharzen., The aim of the investigations was the development of itaconic acid derivatives and the use of these in the production of unsaturated polyester(UP)-resins to expand the possible uses. Use of itaconic acid polyesters in the topcoat area should thus be made possible. One criterion for using UP resins as a topcoat is flexibility. The partial substitution of itaconic acid by methylsuccinic acid leads to a reduction in the crosslinking density and thus enables greater flexibility of the resulting thermoset. Another goal was the substitution of styrene with bio-based reactive diluents. For this purpose, dialkyl itaconates and methyl methacrylate were investigated as reactive diluents. Investigating the derivatization methods of itaconic acid, it was found that the catalytic hydrogenation of IA to methylsuccinic acid is an efficient process. Various supported metal catalysts have been developed, produced reproducibly using simple methods and successfully used in the hydrogenation of itaconic acid. The highest activity was achieved for a bimetal supported catalyst 5% Pd-Pt / SiO2 (Sipernat 22) with 2800 g itaconic acid/h ∙ g metal) at a hydrogen pressure of 5 bar, a reactant concentration of 50 g/L itaconic acid and a reaction volume of 1 L. The stability of the catalyst was investigated over five hydrogenation runs and showed stable activity. A straightforward process of hydrogenating itaconic acid and a polycondensation of itaconic acid-methylsuccinic acid mixtures with 1,3-propanediol made it possible to produce polyester resins based on renewable raw materials using simple methods. Alkyl itaconates and methyl methacrylate as reactive diluents could also be used as an alternative to styrene-based reactive diluents. By varying the itaconic acid content in the polyester resins and changing the reactive diluent, it was possible to show that the flexibility and mechanical properties of the properties of the cured polyester resins can be influenced by the methylsuccinic acid content and the choice of reactive diluent. This enables uses as a laminating resin for fiber-reinforced molded parts or as a polyester resin for topcoat applications. Itaconic acid derivatives can replace styrene in UP resins and in topcoat applications and achieve similar mechanical properties. The products are almost entirely bio-based and meet the increasing demand for bio-based polyester resins.

Festkörperbatterien mit nicht-entflammbaren Festkörperelektrolyten sind eine mögliche Lösung, die Risiken von derzeitigen Lithiumionenbatterien zu überwinden. Im Rahmen dieser Promotion werden die Anwendungseigenschaften von zwei vielversprechenden Festkörperelektrolyten, Lithium-Lanthan-Zirkonium-Oxid (LLZO) und Lithium-Aluminium-Titan-Phosphat (LATP) untersucht. Die SCHOTT AG kann diese über einen skalierbaren Schmelzprozess als glaskeramische Pulver herstellen. Die einzigartige amorphe Phase (φa) dieser Pulver wurde entwickelt, um mehrere Herausforderungen rein keramischer Festkörperelektrolyte zu meistern. Im ersten Teil der Arbeit werden die Bulk- und Oberflächeneigenschaften von mehreren LLZO- und LATP-Pulvern mit unterschiedlichen Anteilen an φa studiert. XRD-Messungen zeigten, dass für die LLZO-Pulver die gezielte Auswahl des Anteils von φa wichtig ist, um schlecht-leitfähige Nebenphasen zu vermeiden. Im Gegensatz dazu kann φa bei LATP variiert werden, ohne dass die hoch-leitfähige kristalline Phase beeinflusst wird. Desweiteren wurde nachgewiesen, dass die Kontamination mit kritischen Oberflächenverunreinigungen, wie H2O und CO2, vergleichbar oder kleiner ist als für typische aus der Literatur bekannte Pulver, welche auf Laborskala hergestellt worden sind. Dennoch ist die Reaktionsgeschwindigkeit mit diesen Gasen sehr schnell, sodass die Prozessierung unter inerten Bedingungen (Taupunkt, All-solid-state batteries with non-flammable solid electrolytes are one possible solution to overcome the risks of state-of-the-art lithium ion batteries. In the framework of this dissertation the application properties of two promising solid electrolytes, Lithium-lanthanum-zirconium-oxide (LLZO) and Lithium-aluminium-titan-phosphate (LATP) were investigated. The SCHOTT AG is able to produce these electrolytes with a scalable process as glass-ceramic powders. The unique amorphous phase (φa) of these powders is intended to overcome several challenges of pure ceramic solid electrolytes. In the first part of this thesis the bulk and surface properties of several glass-ceramic LLZO and LATP powders with different content of φa were studied. X-ray-diffraction measurements revealed that for the LLZO powders the right choice of the amount of φa is important to avoid secondary phases with low conductivity. In contrast φa of LATP could be varied without any influence on the highly conductive crystalline phase. Furthermore, it was proven that the contamination with detrimental surface impurities like H2O or CO2 is equal or less compared to typical powders from literature, which were produced at lab-sale. However, it was found that the reaction with these gases is still very fast, which means processing under inert conditions (dew point

Two-photon polymerization(2PP) is a process for three-dimensional (3D) micro-and Nano structuring based on the locally controlled curing of liquid precursors (light-sensitive resins) by photochemical triggered polymerization. In this decade, will be hearing a lot about this technic being applied to pharmaceutical applications like fabricating 3D microchannels for nanoparticle precipitation, nano-porous membranes and scaffolds for cell culturing, biomimetic organ-on-chip systems. This paper presents 2pp applied microsystems for continuously generating lipid nanoparticles which are one of the most important drug carrier system. The most important advantages of 2pp is manufacturing 3D shapes that is not possible with lithographic micro and nano fabrication technologies. Also, it will be shown how 2pp fabricated microchannel can be integrated with continuous size measurement by flowDLS for the feed-back controlled generation of nanoparticles., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

Antibiotic resistance is undermining public health; it is imperative that new classes of antibiotics are discovered and developed by companies and academic institutions alike. Previous research by this group used the excellent adaptability of N-heterocyclic carbene (NHC)-silver compounds, which allowed for the discovery of the lead compound 1,3-dibenzyl-4,5-diphenylimidazol-2-ylidene silver(I) acetate (SBC3) [1]. SBC3 breaks the methicillin-resistance in Staphylococcus aureus (MRSA) [2] and has proven effective in in vivo tests using Galleria mellonella [3]. More recently, encouraging parts of the antibiotic mechanism of SBC3 were discovered, which underlines the ability of SBC3 to break antibiotic resistance patterns [4]. And SBC3 was tested successfully against biofilms in vitro and against MRSA in-infected mice in vivo [5]. In addition, a telescoped continuous flow route was developed which surpassed the previous batch approach. This provided for a scalable means to afford the targets in higher yield., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

Understanding powder flow and how it affects pharmaceutical manufacturing process performance remains a significant challenge for industry. This work aims to improve decision making for manufacturing route selection, achieving the key goal of digital design within Industry 4.0 of being able to better predict properties whilst minimizing the amount of material required and time to inform process selection during early-stage development. A Machine Learning model approach is proposed to predict the flow properties of new materials from their physical properties. The model’s implementation will enhance manufacturing quality by taking advantage of the data generated throughout the manufacturing process., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

Poorly separable liquid/liquid mixtures often pose a major challenge in pharmaceutical extraction. In particular, compounds containing a low difference of density are difficult to separate using mixer-settler setups. The Zaiput device can prove an advantage over present liquid/liquid extractors. The research work involves characterizing the Zaiput apparatus for liquid/liquid extraction of pharmaceutical compounds with the model solvent system toluene-water. The extraction efficiency was investigated for a solvent mixture containing toluene-acetone-water residence times. To evaluate the separation success, the outlet’s concentrations are measured via IR spectroscopy., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

The poor solubility of a large number of active pharmaceutical ingredients (API) is a major challenge in pharmaceutical research. Therefore, the extrusion of amorphous solid dispersions (ASDs) is one promising approach to enhance the dissolution rate by molecularly dissolve the API in an amorphous carrier polymer. During ASD development, crucial parameters as the dissolution and the decomposition need to be monitored. Within this study, a small scale twin screw extruder was coupled with special ColVisTec UV-Vis probes that are characterized by their small dimensions. This setup enables a systematic formulation development and optimization based on in-line monitoring of crucial parameters using small amounts of material., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

Spherical agglomeration (SA) is a key crystal shape modification technique commonly used to improve processability and physical properties of active pharmaceutical ingredients (APIs), such as flowability and dissolution. SA involves the introduction of a bridging liquid in the form of droplets into a suspension of API crystals. A novel approach was successfully implemented in this study by adopting a membrane emulsification (ME) system to control the size of bridging liquid droplets and spherical agglomerates. The study investigated ways to achieve the critical quality attributes of the spherical agglomerates by varying operating conditions and design parameters, including mixing rate, bridging liquid injection rate and membrane pore diameter. Antisolvent crystallization of benzoic acid in ethanol (solvent) and water (antisolvent) in presence of toluene as a bridging liquid was used as a case study. Spherical agglomerates of benzoic acid with enhanced quality attributes and mean size of 300 μm were obtained using a membrane pore size of 18 μm, a bridging liquid flow rate of 0.025 mL/min and mixing rate in the range of 800 RPM and 1000 RPM., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

Mixing is a crucial parameter for a wide range of processes in bio-/chemical engineering. In multiphase flows, the aim is a high and uniform mixing effect throughout the reaction volume without negative effects on the discrete phase. These are usually caused by the hydromechanical stress exerted by the mixing element. The present study introduces a novel reactor concept to overcome the use of fast rotating, locally acting mixing elements common in stirred tank reactors. Therefore, the reactor is designed of a flat, horizontally mounted cylinder, which enables mixing of the enclosed volume by its rotation around the central axis. To evaluate the mixing performance, a colorimetric method for mixing time determination is presented and the spatial evolution of mixing kinetics visualized. In addition, the method reveals the dependencies of the mixing time on the rotational speed and filling volume., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

Two-phase biocatalysis is commonly used for the bioconversion of water-insoluble chemical and pharmaceutical compounds. In research laboratories, such processes often take place in flasks and are driven and limited by slow diffusive processes. In this work, we developed droplet-based microfluidic systems and used them to perform testosterone dehydrogenation. The use of microdroplets as reaction vessels offers the advantage of greatly improved diffusion rates due to significantly increased surface-to-volume ratio. We found that indeed reaction time was reduced from tens of minutes to tens of seconds without sacrificing conversion efficiency. This demonstrates the potential of droplet-based two-phase biocatalysis., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

Secondary nucleation is widely present in crystallisation processes and it is often relied upon to attain desirable critical quality attributes of crystalline products, such as polymorphic form and crystal size distribution. This is particularly the case in continuous crystallisation, where a good control of secondary nucleation can be crucial in order to achieve and maintain steady state operation. This work utilises rapid, small-scale experiments in agitated vials with in-situ imaging for crystal counting and sizing (using the Crystalline platform), to quantify nucleation and crystal growth kinetics of α-glycine across a range of supersaturations in aqueous solutions under isothermal conditions. Both seeded and unseeded crystallisation experiments were conducted. It was found that secondary nucleation and crystal growth rates determined from the same vials show a close correlation across the whole range of supersaturations investigated, which suggest a close relationship between the mechanisms of shear induced secondary nucleation and crystal growth in this system., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

Amorphous solid dispersions (ASDs) of a poorly water-soluble active pharmaceutical ingredient (API) in a polymer matrix can enhance the water solubility and improve the bioavailability of the API. Many ASD products are kinetically stabilized, and the inhibition of crystallization of an API within and beyond shelf life is still a matter of debate, since the formation of crystals may impact bioavailability. We present the first literature examples of ASD long-term stability studies over up to 25 years under ambient storage conditions where no API crystallization was observed. Additionally, a risk assessment and mitigation strategy of API crystallization in packaged ASD drug products (DP) is outlined. The risk of shelf-life crystallization and the respective mitigation steps are assigned for different DP development scenarios. Ultimately, the physical stability of ASD DPs during shelf-life storage is modeled by quantifying crystal growth kinetics by transmission Raman spectroscopy (TRS), modeling the impact of water sorption on the glass-transition temperature of the ASD, and predicting the moisture uptake by the packaged ASD DP during storage. This approach is applied to an ASD of an AbbVie-internal compound showing stability beyond the anticipated shelf-life., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

The cryopreservation of cells and tissue engineered constructs is determined by multiple factors, such as possible cellular damages due to mass and heat transfer during the freezing and thawing process. It is assumed that the utilization of cryobags improves the heat transfer during freezing and thawing and is therefore superior in comparison to currently applied cryovials and multiwell plates. Therefore, we have analysed the cryopreservation of cell-seeded electrospun polycaprolactone/polylactide scaffolds within cryobags. Additionally, the performance of four different cryoprotective agents was analysed, which included 10% (v/v) dimethyl sulfoxide and 10% (v/v) ethylene glycol as separately applied agents as well as their combination with 0.3 M sucrose. The samples were frozen in in-house made cryobags with a controlled rate freezer. The cell viability was analysed by fluorescence microscopy before freezing and after thawing. The results show, that the application of cryobags in combination with 10% (v/v) ethylene glycol can have a positive impact onto the cell viability., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

Without any doubt the young technology of additive manufacturing, including 2D and 3D printing, has been changing the world. A wide spectrum of objects in medical and pharmaceutical field can already be successfully printed. This ranges from a detailed figure in the micrometer regime to a full size residential house unit made from concrete [Sakin et al., 2017; Doherty et al., 2020]. In the pharmaceutical sector, additive manufacturing offers the option of medication customization [Pravin et al., 2018]. Integrating this new technology has several advantages over the current, well-established but outdated “one-size-fits-all” approach. Besides avoiding medication errors, printing tailored oral dosage forms is financially attractive for small scale on-demand production [Awad et al., 2018]. The development of dosage forms, production of sample batches and modification of samples can be done with little effort compared to generic powder-pressed pills which require heavy pharmaceutical machinery [Awad et al., 2018; Dachtler et al., 2020]. To further progress and to create the legal framework for the approval of additively manufactured drugs it requires a paradigm change of stakeholders who have the power to make decisions and changes [Horst et al., 2019]., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

In December 2019, a series of pneumonia of unknown cause emerged in Wuhan, China, which developed into a global pandemic with more than 200 million cases and 4 million deaths worldwide as of August 2021. The enveloped RNA betacoronavirus which was found to cause the pandemic was named severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Academia and industry started with non-clinical and clinical development of several SARS-CoV-2 vaccine candidates immediately and results were achieved enormously fast. As an example, BioNTech and Pfizer got their joint SARS-CoV-2 vaccine approved less than eight months after trials started, while under normal circumstances vaccine development takes up to 10 – 15 years. In the case of the SARS-CoV-2 vaccine the extremely fast turnaround time from start of clinical trials to approval of the first vaccine candidates was driven by the urgent medical need and made possible by the mobilisation of enormous financial resources from the private and public sectors, as well as manpower and effort and the willingness of regulators to speed up timelines and approval processes. Looking at the extremely fast and successful development of several SARS-CoV-2 vaccine candidates, it is difficult to understand from a layman’s perspective why for others diseases like Human Immunodeficiency Virus/ Acquired Immunodeficiency Syndrome (HIV/AIDS) and tuberculosis (TB), which are among the top ten causes of death worldwide, development of effective vaccines takes so long. More than 30 years after HIV has been discovered, there is still no vaccine available for prevention of HIV infection. Development of several vaccine candidates has failed in clinical trials. The difficulties stem in large part from HIV’s unusual characteristics of replicating and mutating rapidly and high sequence diversity, its ability of immune system evasion and the creation of a persistent viral reservoir within the host. Development of the novel TB vaccine candidate VPM1002, which is designed to be a safe and effective vaccine for prevention of TB infection and TB recurrence, is an example of classical vaccine development. VPM1002 was invented in Germany, went through successful non-clinical development and is currently being tested in phase III clinical trial. The achievements during the last year fast development of SARS-CoV-2 vaccines during the last year have proven that in case of a pandemic situation and an urgent medical need, fast vaccine development is possible. The achievements were reached with high financial commitment and regulators have shown willingness and engagement to accelerate timelines for review and approval processes. It would be desirable if further vaccine developments could benefit from these efforts., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

Polymerized Ionic Liquids (PILs) are hydrogels synthesized from ionic liquids. They combine the positive characteristics of ionic liquids and polymers which is why they have a wide range of applications, e.g. in the pharmaceutical sector. They are characterized by properties such as high mechanical strength, biocompatibility, and favorable swelling behavior. In this study, the extremely high mechanical strength of novel polymerized ionic liquids (PILs)-based hydrogels was confirmed by mechanical tests. The swelling behavior was studied of hydrogels based on 1-Vinyl-3-alkylimidazolium bromide with different crosslinkers in various solvents – aqueous and organic., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

Encapsulation of clinically relevant cells, such as multipotent stromal cells (MSCs), in three-dimensional (3D) core-shell alginate structures is a promising method for the treatment of various diseases as well as drug testing and development. By utilizing the alginate capsules, drugs and active substances can be delivered specifically to the desired place within the patients’ body. The aim of this work was to investigate the effect of cryopreservation on the integrity of cell-free coaxial alginate capsules after thawing using slow freezing to ensure their long-term storage. Alginate capsules were produced by electro-spraying and cryopreserved using different cryoprotective agents (CPAs), incubation time and thawing temperature. The results suggest that the capsules loaded with 10% (v/v) dimethyl sulfoxide (DMSO) and 0.3 M sucrose and using high thawing rates demonstrated a beneficial effect on the integrity of capsules, as compared to 10% (v/v) DMSO alone and applying low thawing rates. This study is a further development towards the application of cryopreservation for long-term storage and the emerging cell-based medicine., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

Dermatoses are skin diseases caused by lowered level of lipids in the intercellular lipid matrix of skin’s uppermost layer stratum corneum. A promising therapy is the application of liposomally formulated skin lipids (ceramides, cholesterol, fatty acids). These so called cerosomes proved very effective in disrupted skin barrier repair; however, they aim primarily on a mechanical surface restoration. For this reason an interesting idea is to combine the cerosomes and anti-inflammatory drugs (such as hydrocortisone) used for the treatment of pathophysiological processes in the skin. Unfortunately, liposomes generally show low drug encapsulation rates, hence they would not be very effective carriers. On the other hand, great encapsulation effectivity can be found in lipid nanocapsules (LNCs). We therefore aimed to create a combined system cerosomes-LNCs that would ensure the skin barrier restoration thanks to the ceramides and simultaneously effectively deliver hydrocortisone as a representative of anti-inflammatory drugs into lower layers of the skin. In this work, we characterized the formulations by dynamic light scattering and transmission electron microscopy to assess their size and morphology., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

In this study, a novel approach was developed for determining the density of compacts using ultraviolet–visible spectrophotometry. The assumption within this context was that a change in density affects the corresponding color information of the compact. From the obtained spectra of the visible range, the color information of the compact was calculated which turned out to be directly proportional to the density of the compact. In comparison, the obtained spectra were analyzed using partial least square regression. The results of this study showed that both methods could be used predicting the density of a compact from the corresponding visible spectrum at identical accuracy. In contrast to the partial least square regression, the correlation of the color information as a direct output parameter of the spectrophotometer with the density required no excessive data pre-processing. Subsequently, the easier and faster data processing of the color information over the partial least square regression, conceives using this novel approach as potential process analytical technology tool for implementation into a compression process e.g., tableting or roller compaction., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

Die Hämoglobinkonzentration in Blut ist einer der am häufigsten gemessenen Parameter. Für Hämoglobin ist die am häufigsten eingesetzte Messmethode die Cyanmethämoglobinmethode. Diese ist nicht auf das internationale Einheitensystem rückgeführt. Die Entwicklung von Verfahren, die eine metrologische Rückführbarkeit gewährleisten, ist in den letzten stark in den Vordergrund der Aktivitäten nationaler Metrologieinstitute gerückt. In dieser Arbeit wurde daher versucht einen vergleichbaren Immunoassay, basierend auf der oberflächenverstärkten Raman-Spektroskopie zu entwickeln. Die Kombination mit der Isotopenverdünnung (ID) ermöglicht präzise Messungen in selbst kleinsten Konzentrationsbereichen. Die Detektion des Hämoglobins erfolgt indirekt durch die Verwendung des ramanaktiven Markers 5,5′-Dithiobis-2-nitrobenzoesäure (DTNB) welcher auf Goldnanopartikeln mit einem Durchmesser von 40 nm immobilisiert wurde. Neben DTNB in nativer Form wurde für die Durchführung der ID ebenfalls ein isotopenangereichertes Analogon benötigt. Für einen erfolgreichen Immunoassay wurden weitere Funktionalisierungen der AuNP mit monoklonalen Antikörpern und einem zertifizierten Hämoglobin mit bekannter Konzentration durchgeführt. Die Funktionalisierungen der AuNP wurden eingehend mit Verfahren wie der UV/Vis-Spektroskopie, der Agarose-Gelelektrophorese und der Röntgenkleinwinkelstreuung untersucht. Der Nachweis der Spezifizität von monoklonalen sowie polyklonalen Antikörpern für Hämoglobin wurde mittels Gelelektrophorese überprüft. Für die Realisierung der ID wurden die AuNP entweder mit DTNB (+ Antikörper, + Hämoglobin) oder mit DTNB* (+ Antikörper, + Hämoglobin) in bestimmten äquidistanten Verhältnissen gemischt. Das höhere molekulare Gewicht des führt zu einer Verschiebung der Raman-Spektren, die in Kombination mit den Mischungsverhältnissen eine Bestimmung der (unbekannten) Proteinkonzentration ermöglicht. Durch die Kenntnis der für die Mischungsverhältnisse verwendeten Mengen (Nanopartikel, DTNB und Hämoglobin) kann eine Berechnung der unbekannten Konzentration erfolgen. Es wurden verschiedene Oberflächen wie Cellulosenitrat-Membranen und Glaswafer zum Immobilisieren getestet. Glaswafer zeigten sich als zielführend und ermöglichten die Erstellung eines Testformates des SERS-Immunoassays. Aufgrund der Problematik einer Aggregation der Partikel kann das Testformat des ID-SERS-Immunoassays nur eingeschränkt verwendet werden., Haemoglobin is one of the most frequently measured parameters in laboratory medicine. The only approved method for the detection of haemoglobin concentration the cyanmethaemoglobin method is not traceable to the SI. In general, there are severe problems in comparability of results in clinical laboratories and they can vary depending on the used testing kit. Raising from the problem of this lacking comparability and traceability the scope of this research was the development of a SERS-Immunoassay in combination with the Isotope Dilution approach which, is capable of an SI traceable quantification of haemoglobin. The detection of haemoglobin was performed indirect due to the usage of the strong Raman active marker DTNB. The aimed quantification of haemoglobin required additionally an isotopic enriched analogue of this marker. The used spherical goldnanoparticles with a size of 40 nm were functionalized with DTNB and its isotopologue and specific antibodies targeted against haemoglobin. The functionalization could be proved with different methods like UV/Vis, SAXS and agarose gel-electrophoresis. The specificity between antibodies and haemoglobin was successfully tested with Western blotting. This nanoparticle antibody complex was able to specific bind the haemoglobin and could be immobilized on a functionalized nitrocellulose membrane. The nitrocellulose-based approach appeared not to be suitable for a further development of the Immunoassay and an alternative was chosen. Due to these reasons an alternative approach with modified glass slides was executed. The alternative approach managed to minimize potential nanoparticle aggregation. With the achieved spectra a first try for a successful calibration model was made but with some limitations of the model itself. There are noticeable differences between the model based on the nitrocellulose membrane and the slides. Despite the influences of the nanoparticles, the ID-SERS-Immunoassay can be the basis for a further improvement of the quantification model for haemoglobin.

In situ tissue engineering requires to functionalize the surfaces of implants, to achieve better biocompatibility or to release pharmaceuticals. Often a burst release of such pharmaceuticals takes place and the surface functionality is gone rapidly. Casein-micelles (M-Cas) offer unique release capabilities for hydrophobic and hydrophilic substances. In this work, M-Cas were reconstructed and used as release system for curcumin as a model drug. Modified electrospun polycaprolactone (PCL)-fiber mats were coated with chitosan / tripolyphosphate nanoparticles (CS/TPP-NP) and functionalized with the reconstructed M-Cas. [1] CS/TPP-NPs and Na-caseinate (Cas) were used as blocking layer to slow down the release of curcumin loaded micelles. The layers were investigated by surface zeta-potential (ZP). The release of the curcumin from surfaces was possible and the blocking layers had a significant influence on the kinetics., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

Solid triglyceride nanoparticles are under intensive investigation as drug delivery systems. In the solid state, triglycerides exist in three polymorphic modifications which differ from each other in their physicochemical properties. Thus, it is particularly important to know the influence of parameters affecting the polymorphic behavior of the solid triglyceride nanoparticles to get a stable product with defined physicochemical properties over an appropriate storage time. This study investigated the effect of subsequent addition of SDS to tripalmitin nanoparticles, which had been stabilized with partially hydrolyzed poly(vinyl alcohol) (PVA). The polymorphic behavior was characterized with DSC and X-ray diffraction over a storage time of 28 d at 20 °C. A faster transition into more stable polymorphic modifications was observed after the addition of SDS to the nanoparticles., SPhERe Proceedings: 4th International Symposium on Pharmaceutical Engineering Research

Es wurden biobasierte Polyester und Polyestermischungen entwickelt, mit dem Ziel, diese zur kommerziellen Verklebung von Papier- und Kartonverpackungen zu nutzen. Die Polyester basieren auf Bernsteinsäure, die zu Polybutylensuccinat (PBS), Polyethylensuccinat (PES), Poly 1,2 propylensuccinat (P1,2PS), Poly 2,3 butylensuccinat (P2,3BS) und Poly 1,3 propylensuccinat (P1,3PS) umgesetzt wurde. PBS weist die höchste Reaktivität unter den hier hergestellten Polyestern auf. Mit einer kurzen Reaktionszeit von 4 h konnten hohe Molmassen von bis zu 82.000 g/mol erreicht werden. PBS hat den höchsten Tm mit 113 °C und vereint mit einer Tg von 29 °C einen niedrigen Glasübergangspunkt mit einem hohen Schmelzpunkt. Alle Polyester zeigen Fließverhalten, welche von der Scherrate unabhängig sind. Es wurden die Ruhescherviskositäten, die eta Mw Beziehungen bestimmt und die Aktvierungsenergien des Fließens bestimmt. Mischungen der Polyester wurden mittels Dynamisch Mechanische Analyse (DMA) untersucht. Mischungen aus PBS und P1,3PS sowie PBS und P1,2PS zeigen eine vollständige Mischbarkeit. Alle weiteren Mischungen zeigen in Abhängigkeit von der Zusammensetzung maximal eine teilweise Mischbarkeit. Polyethylenglycol 600 (PEG600) wurden als Weichmacher für PBS untersucht. Es kann die Härte, Viskosität und die Tg herabsetzen und ist gut mischbar. Zur Beurteilung der thermischen Stabilitäten des PBS wurden die Viskositäten der Schmelzen über Zeiträume von bis zu 48 h bei 150 °C kontinuierlich gemessen. Zur Stabilisierung wurde Bis(2,6-diisopropylphenyl)carbodiimid (BDICDI), Bis(2,4-di-tert-butylphenyl)pentaerythritoldiphosphat (BTBP) und ein polymeres Carbodiimid (Handelsname: BioAdimide 500 XT (BioA)) verwendet. Mit einer Mischung aus 3,0 Gew. % BDICD, 0,2 Gew. % BTBP und 0,2 Gew. % BioA ist eine Stabilisierung der Viskosität bei einer maximalen Viskositätsänderung von 9,6 % innerhalb 48 h gelungen. ESBO wurde als bio-basierter Stabilisator getestet. Mit 0,5 Gew. % wird über 48 h eine annähernd konstante Viskosität des Polybutylensuccinats erreicht. PBS ein PBS/P1,2PS Blend und PBS/P1,2PS/PEG600 Blend wurden klebtechnisch untersucht. Der PBS/P1,2PS Blend und der zusätzlich durch PEG600 modifizierte Blend weisen mechanische Eigenschaften auf, die denen kommerziellen Schmelzklebstoffe nahe kommen., Bio-based polyesters and polyester blends have been developed with the aim of using them for the commercial bonding of paper and cardboard packaging. The polyesters are based on succinic acid, which was converted into polybutylene succinate (PBS), polyethylene succinate (PES), poly 1,2 propylene succinate (P1,2PS), poly 2,3 butylene succinate (P2,3BS) and poly 1,3 propylene succinate (P1,3PS). PBS shows the highest reactivity among the polyesters produced here. With a short reaction time of 4 h high molar masses of up to 82,000 g/mol could be achieved. PBS has the highest Tm at 113 °C and combines a low glass transition point with a high melting point at a Tg of 29 °C. All polyesters show flow properties which are independent of the shear rate. The quiescent shear viscosities, the eta Mw relationships and the activation energies of the flow were determined. Blends of the polyesters were investigated by means of dynamic mechanical analysis (DMA). Blends of PBS and P1.3PS as well as PBS and P1.2PS show complete miscibility. All other blends show a maximum of partial miscibility depending on the composition. Polyethylene glycol 600 (PEG600) was investigated as plasticizer for PBS. It can reduce hardness, viscosity and Tg and is well miscible. To assess the thermal stability of PBS, the viscosities of the melts were measured continuously over periods of up to 48 h at 150 °C. For stabilization, bis(2,6-diisopropylphenyl)carbodiimide (BDICDI), bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphate (BTBP) and a polymeric carbodiimide (trade name: BioAdimide 500 XT (BioA)) were used. With a mixture of 3.0 wt. % BDICD, 0.2 wt. % BTBP and 0.2 wt. % BioA, a stabilisation of the viscosity at a maximum viscosity change of 9.6 % within 48 h was achieved. ESBO was tested as a bio-based stabiliser. At 0.5 wt.%, an almost constant viscosity of the polybutylene succinate is achieved over 48 h. PBS, a PBS/P1,2PS blend and PBS/P1.2PS/PEG600 blend were tested for adhesion. The PBS/P1,2PS Blend and the additionally modified PEG600 Blend show mechanical properties that are close to those of commercial hot melt adhesives.

Multi-block glucans comprising permethylated and partially methylated blocks are compounds of interest. In order to monitor their formation by transglycosylation of corresponding starting glucans, a method has been developed and applied to model compounds. This method allows determining the average length of the blocks and the progress of incorporation of methyl blocks in partially methylated sequences with a random distribution. The method, comprising liquid chromatography mass spectrometry (LC-MS) and electrospray ionization collision-induced dissociation tandem mass spectrometry (ESI-CID-MSn) measurements of two types of peralkylated glucans representing derivatives of the target compounds, is comprehensively described and discussed. ESI-MSn allows looking into the sequences of oligomeric domains. In addition, transglycosylation is followed by attenuated total reflection FTIR and NMR spectroscopy. Graphical abstract Electronic supplementary material The online version of this article (10.1007/s00216-020-02388-z) contains supplementary material, which is available to authorized users.

Novel Polymerized Ionic Liquids (PILs)-based Hydrogels as Innovative Drug Delivery Systems are presented. The embedding of drugs in hydrogels enables the “smart” delivery of bioactive molecules from drugs for an oral route of administration. Therefore, a high mechanical strength as well as a favorable pH-dependent swelling behavior is required which is shown in this study. A mechanical compression of PILs-based hydrogels up to 98.5% and a high swelling behavior of poly(VEImBr) hydrogels in a solution with a high pH value is achieved. A significant lower swelling is achieved in a solution with a lower pH value., SPhERe Proceedings: 3rd International Symposium on Pharmaceutical Engineering Research

Polycyclic polyprenylated acylphloroglucinols (PPAPs) exhibit a broad range of biological activities, such as antidepressant, antibacterial, antiviral and antitumor properties. The content of PPAPs in the producing plants is often quite low, and their complex structures make total chemical synthesis difficult and economically impractical. Progresses in synthetic biology provide an alternative approach for the production of these valuable compounds. Here we present our results on reconstruction of the biosynthetic pathways of PPAP precursors in yeast. Based on our previous works on the biosynthesis of PPAPs, genes involved in the formation of benzophenones and xanthones from Hypericum sp. and other organisms were expressed in yeast either episomally or by integration into the genome. The production of the expected products reached around 0.5 mg/l, which is high enough to be the substrate for enzymes of subsequent biosynthetic steps. The yeast strains will be further engineered by introducing various prenyltransferase enzymes to reconstruct the full biosynthetic pathways of PPAPs., SPhERe Proceedings: 3rd International Symposium on Pharmaceutical Engineering Research

A sufficient mechanical stability of tablets to be compacted prevents problems during tableting (e.g. sticking, capping, lamination) and is crucial with regard to further processing steps such as coating or packaging. Often, an improvement of the mechanical stability is only achievable by an adaption of the production settings (die disk speed) or an alteration of the powder blend composition. In the present study, a novel lower punch vibration device was developed and implemented on a rotary tablet press to improve the mechanical stability of the resulting tablets without changing the production conditions or the powder formulation. Various types of microcrystalline cellulose with different physical properties were selected. The powders were investigated concerning their powder flow, density, particle morphology and surface area and the tablets concerning their weight, tensile strength, and capping index. The results showed that externally applied lower punch vibration improved the mechanical stability of the investigated tablets beyond the adaption of the production settingss and the physical properties of the powder blend., SPhERe Proceedings: 3rd International Symposium on Pharmaceutical Engineering Research

The successful transfer from batch to a continuous flow process in a fixed bed reactor of a ligand in metalorganic API synthesis, the diazolium salt 1,3-methyl-benzoimidazol-3-ium iodide, is presented. Results show similar yields and conversion rates at corresponding process parameters in batch and continuous mode. By exceeding temperature limitation of a non-pressurized batch process, the pressurized continuous reactor system shows the potential for outperforming the batch synthesis regarding space time yield. Hence, process intensification by continuous flow presents itself as a viable approach for the heterogeneous di-N-alkylation of diazoles. Alternative basic reagents and solvents further enhance the viability of a continuous approach by addressing limitations such as side reactions and solubility of the reagent., SPhERe Proceedings: 3rd International Symposium on Pharmaceutical Engineering Research

As one of the current and next-generation energy storage devices, lithium-ion batteries and supercapacitors have potential for improved design for lower cost, higher safety and efficiency, compared with recent status. The major development of lithium-ion batteries and supercapacitors is currently driven by the experimental approaches, which cost much time and lack deep insight into interacted multiphysics processes. Multiphysics modelling approach can overcome such drawbacks, and thus be used for investigation and discovery of new materials and device design. For lithium-ion batteries, a novel 3D multiphysics model was developed to discover such heterogeneously physical interactions in a 12Ah pouch cell based on operation principles. The model analyzes the internal interactions of local thermal effects, electrochemical and electric performance on electro-active layers in the pouch cell. It illustrates that the poor heat dissipation and high heat generation causes strong thermal heterogeneity at large currents, which finally results in intense local interactions of electric and electrochemical performance. This 3D multiphysics model is applied into a global sensitivity analysis of the same cell for the utilizable discharge capacity and local maximum temperature at 1C. The sensitivity analysis is efficiently executed for 46 parameters in this 3D model. Consequently, it reveals that the capacity and the local maximum temperature are both most sensitive to geometric parameters of electrodes and their pore structures. Following these results, a large-format prismatic battery was optimized with the detailed 3D geometries and components for upgrading safety prevention of thermal-runaway and maximizing the capacity. For supercapacitors, a novel multiphysics pseudo-2D model is developed to interpret complex faradaic reaction mechanisms and investigate effects of different pore structures on capacitive performance. Symmetric cells of cuprous oxide and hierarchical porous carbon are parameterized respectively, with good agreement between experimental data and simulated results at the room temperature. The simulation results imply that the effective ion size and micropore volume can strongly affect the double layer capacitance due to the change of ion transport in double layers and pores. This multiphysics model is the first to interpret the capacitive behavior in hierarchical pore structures based on attractive force theory and modified Donnan concepts, to my best knowledge., Lithium-Ionen-Batterien und Superkondensatoren sind Energiespeicher der aktuellen und nächsten Generation. Sie weisen ein höheres Potential bezüglich eines verbesserten Designs und einer Kostenreduktion auf. Die Entwicklung von Lithium-Ionen-Batterien und Superkondensatoren basiert derzeit hauptsächlich auf experimentellen Ansätzen, die viel Zeit kosten und keinen tiefen Einblick in interagierende multiphysikalischen Prozesse bieten. Der Ansatz eine Multiphysikmodellierung kann diese Nachteile überwinden und somit zur Untersuchung und Entdeckung neuer Materialien und Bauelemente verwendet werden. Im Bereich Lithium-Ionen-Batterien wurde hierzu ein neuartiges 3D-Multiphysikmodell entwickelt, welches die heterogenen physikalischen Wechselwirkungen in einer 12-Ah-Pouchzelle berücksichtigt. Das Analyseergebnisse zeigen, dass eine schlechte Wärmeableitung und hohe Wärmeerzeugung bei großen Strömen eine starke thermische Heterogenität verursacht, die schließlich zu starken lokalen Wechselwirkungen zwischen elektrischer und elektrochemischer Leistungsfähigkeit führt. Das 3D-Multiphysikmodell wird darüber hinaus für eine globale Sensitivitätsanalyse einer Pouchzelle in Bezug auf die nutzbare Entladekapazität und die lokale Maximaltemperatur bei 1C verwendet. Die Sensitivitätsanalyse wurde mit 46 Parametern durchgeführt. Es zeigt sich, dass sowohl die Kapazität als auch die lokale Maximaltemperatur die höchste Sensitivität gegenüber der geometrischen Parameter der Elektroden und deren Porenstrukturen aufweist. Basierend auf diesen Ergebnissen wurde eine großformatige prismatische Batterie mit detaillierten 3D-Geometrien und -Komponenten optimiert, um die Sicherheit gegen thermisches Durchgehen zu verbessern und die Kapazität zu maximieren. Für Superkondensatoren wurde ein neuartiges multiphysikalisches Pseudo-2D-Modell entwickelt, welches die Interpretation von komplexen faradayschen Reaktionsmechanismen und die Untersuchung der Auswirkungen verschiedener Porenstrukturen auf die kapazitive Leistung ermöglicht. Dabei konnten durch eine Modellparametrierung eine gute Übereinstimmung zwischen der Simulation und experimentellen Daten für symmetrische Zellen aus Kupferoxid und hierarchischen porösem Kohlenstoffen erzielt werden. Die Simulationsergebnisse implizieren, dass die effektive Größe der Ionen und das Mikroporenvolumen die Doppelschichtkapazität aufgrund der Änderung des Ionentransports in Doppelschichten und Poren stark beeinflussen können. Nach meinem besten Wissen ermöglicht dieses Multiphysikmodell erstmals die Interpretation des kapazitiven Verhaltens in hierarchischen Porenstrukturen basierend auf der „attractive force“-Theorie und eines modifizierten Donnan Ansatzes. Es kann viel zur Optimierung der Superkondensatorelektrodenstrukturen beitragen, um eine bessere kapazitive Leistung zu erzielen.