Analytische Chemie
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- 2017 (18) (entfernen)
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- Antibodies (2)
- Laser ablation ICP-MS (2)
- AAAA (1)
- AdvanceBio Peptide Map (1)
- Antibody (1)
- Antibody ID (1)
- Antibody immobilization (1)
- Aqueous Solutions (1)
- Aromatic amino acid analysis (1)
- Aromatische Aminosäuren (1)
Ausgehend von dem in der Literatur beschriebenen Verfahren zur Bestimmung aromatischer Aminosäuren konnte eine Analysemethode zur Proteinbestimmung über die optische Detektion von Tyrosin und Phenylalanin nach chromatographischer Trennung der Protein-Hydrolysate entwickelt werden, die gegenüber dem Verfahren aus der Literatur erhebliche Vorteile besitzt. Der Einsatz von Rundbodenvials stellt eine Neuerung und kostengünstige Alternative zu der konventionellen Hydrolyse in Vakuumhydrolyseröhrchen wie auch zu den Mikrowellenvials der Mikrowellenhydrolyse dar, die das Potential für Miniaturisierungen der Proben hat und sich zudem für große Probendurchsätze eignet. Anstelle der Mikrowellenheizungen wurde ein konventionelles Ölbad als Heizquelle verwendet. Somit ergibt sich eine Verbesserung auch darin, dass diese Methode geringere Geräteinvestitionen erfordert. Wie die Ergebnisse nahelegen, sind sowohl Salzsäure als auch Bromwasserstoffsäure geeignete Reagenzien, die bei der sauren Hydrolyse von Proteinen verwendet werden können. Mit Hilfe antioxidativer Zusätze können Nebenreaktionen erfolgreich vermieden werden. Hier haben sich L-Cystein und Oxalsäure als wirkungsvolle Additive herausgestellt. Wichtige Verbesserungen betreffen vor allem die Zeitersparnis bei der Hydrolyse, die Aufarbeitung der Hydrolysate und die chromatographischen Separationen. Erstere konnte gegenüber der konventionellen Methode von 22 Stunden auf 45 Minuten reduziert werden. Die chromatographische Trennung wurde so weit optimiert, dass die Laufzeit von 64 auf 35 Minuten verkürzt werden konnte. Zudem konnte auf das zeitraubende und kontaminationsanfällige Eindampfen der Hydrolysate verzichtet werden. Während der Aufarbeitung der Hydrolysate konnten die Menge eingesetzter Chemikalien reduziert und damit mögliche Störungen während der optischen Detektion verringert werden. Letztere wurde zum einen durch das Einbeziehen der UV-Absorption bei 260 nm erweitert, sodass eine Alternative zur Absorption bei 215 nm vorliegt, die ebenere Basislinien im Chromatogramm ermöglicht. Zum anderen wurde gezeigt, dass mit Hilfe der Fluoreszenz die Empfindlichkeit der Methode gegenüber der UV-Absorption erheblich verbessert werden kann. Anhand der Probe eines Birkenpollenextraktes ließ sich die Anwendbarkeit der optimierten Methode auf Realproben demonstrieren.
In this thesis a protocol based on a direct competitive and non-competitive immunoassay using the microarray format was developed to screen emulated hybridoma supernatants against the drug carbamazepine (CBZ). As support, epoxy slides were manufactured by coating microscope glass slides with epoxy silanes. The manufactured epoxy slides showed similar capacity for protein immobilization as commercially available NEXTERION slides, but showed a higher autofluorescence background. On the epoxy slides, protein A, Cys-A, G and Cys-G were immobilized as antibody capturing coating. It could be shown that the Cys-tag considerably increased the immobilization of all compared proteins, especially of protein G. Protein Cys-G immobilized at pH 8-9 was considered the most suitable protein for antibody immobilization due to good spot uniformity and a high binding capacity for IgG. Additionally, in immobilization experiments it could be shown, that 10-500 fold excess of bovine IgG, introduced by two different fetal bovine serum (FBS) products, showed no significant competition on the immobilization of mice or goat IgG on protein Cys-G. To examine the captured antibodies for affinity to CBZ, the CBZ-TOTA-DY654 tracer was custom synthesized. It could be demonstrated, that the tracer antibody interaction was competitive with the tracer precursor, CBZ-TOTA-NH2 and CBZ. Furthermore, the synthesized tracer was also successfully used by externals to evaluate CBZ affine hybriodoma cells in flow cytometry. In the simulated screening, five antibodies with known affinity to CBZ were diluted in a cell culture medium. The screening method allowed to differentiate between affine antibodies (IC50 < 20 µg/ml) and unaffine antibodies (IC50 > 20 µg/ml), when concentrations of 0.1 µg/ml IgG or greater have been used. Of five applied antibodies, all highly affine clones (CE2 and B3212M) were reported as positives while no false-positive samples were observed. The screening included competitive, with around 89500 fold excess of CBZ, and non-competitive tracer incubation on different segments of the same chip, which resulted in total signal suppression on the competitive segment. The screening was performed in 20 hours, only a few nanoliters, of each simulated supernatant, were consumed in the screening process, furthermore in the method standard 96 well MTPs were used and no cleanroom facilities were required.
Präsentation der Ergebnisse eines Ringversuchs zur Kompetenzbewertung von Prüflaboratorien auf dem Gebiet der anorganischen und organischen Bodenanalytik: Polyzyklische aromatische Kohlenwasserstoffe (PAK) in Boden, Mineralölkohlenwasserstoffe (MKW) in Boden, Elemente in Sediment und Gesamtcyanid in Boden.
Research and Development in Non-Destructive Testing in Civil Engineering at BAM has de-veloped over more than two decades. Highlights of present research are ultrasound phase array probes, ground penetrating radar applications for the assessment of existing structures and Laser Induced Breakdown Spec-troscopy (LIBS) to determine which chemical elements on the surface of a specimen are. RFID sensor devel-opments for wireless moisture monitoring and data fusion for the combined analysis of sensor data are fast developing areas. In addition, a selection of application cases is briefly described.
Fast and robust purification of antibodies from human serum with a new monolithic protein A column
(2017)
The use of antibodies is becoming more and more important. Therewith the need for fast and robust methods for their purification and columns with a long lifetime is growing. In this application, we describe a fast and robust protein A affinity chromatography method with a new monolithic column. Antibodies were successfully purified in less than 1.5 minutes with a flowrate of 5 mL/min highlighting the advantages of this column and method.
Lecture 7: Speciation
(2017)
ICP-MS is a well-established analytical method which excels by high accuracy, high dynamic range and extremely low limits of detection for most metals. Furthermore ICP-MS offers a very high multi-element coverage so that many elements of the periodic table can be detected simultaneously. In this series of lectures, we want to focus on the historical developments, fundamentals, instrumentation and novel applications of ICP-MS in the life and material sciences.
ICP-MS is a well-established analytical method which excels by high accuracy, high dynamic range and extremely low limits of detection for most metals. Furthermore ICP-MS offers a very high multi-element coverage so that many elements of the periodic table can be detected simultaneously. In this series of lectures, we want to focus on the historical developments, fundamentals, instrumentation and novel applications of ICP-MS in the life and material sciences.
ICP-MS is a well-established analytical method which excels by high accuracy, high dynamic range and extremely low limits of detection for most metals. Furthermore ICP-MS offers a very high multi-element coverage so that many elements of the periodic table can be detected simultaneously. In this series of lectures, we want to focus on the historical developments, fundamentals, instrumentation and novel applications of ICP-MS in the life and material sciences.
Non-spectral interferences
(2017)
ICP-MS is a well-established analytical method which excels by high accuracy, high dynamic range and extremely low limits of detection for most metals. Furthermore ICP-MS offers a very high multi-element coverage so that many elements of the periodic table can be detected simultaneously. In this series of lectures, we want to focus on the historical developments, fundamentals, instrumentation and novel applications of ICP-MS in the life and material sciences.
Short course on ICP-MS
(2017)
ICP-MS is a well-established analytical method which excels by high accuracy, high dynamic range and extremely low limits of detection for most metals. Furthermore ICP-MS offers a very high multi-element coverage so that many elements of the periodic table can be detected simultaneously. In this series of lectures, we want to focus on the historical developments, fundamentals, instrumentation and novel applications of ICP-MS in the life and material sciences.