@misc{MirskyMassKrauseetal., author = {Mirsky, Vladimir M. and Mass, Markus and Krause, Christian and Wolfbeis, Otto S.}, title = {Capacitive approach to determine phospholipase A2 activity towards artificial and natural substrates}, series = {Analytical Chemistry}, volume = {70}, journal = {Analytical Chemistry}, number = {17}, issn = {0003-2700}, doi = {10.1021/ac980102w}, pages = {3674 -- 3678}, abstract = {A capacitive approach has been employed to develop a novel method to determine phospholipase activity. The sensing electrodes have a structure like Au/S(CH₂)₁₇CH₃/substrate/electrolyte. Hydrolysis of the substrate, mediated by phospholipase A₂, leads to the formation of water-soluble products from the insoluble substrate. This results in desorption of these products into aqueous phase and corresponding increase of the electrode capacitance. The requirement of high water solubility of the reaction products can be achieved in two ways. In the first, short-chain phospholipids are used as the substrate, in which case, water-soluble products are formed and no additional reagents are required to promote desorption of these products. The sensors prepared by this strategy provide sensitive qualitative detection of phospholipases. The second way is based on the use of a water-soluble acceptor (for example, β-cyclodextrin) to solubilize the products of hydrolysis. It allows semiquantitative detection of phospholipase activity toward long-chain natural substrates. The reaction kinetics for this case was found to be monoexponential and linearly dependent on the phospholipase concentration. The detection limit of this method, as tested with phospholipase A₂ from bee venom and soy bean lecithin as the substrate, is ∼0.5 ng/mL (500 μunits/mL).}, language = {en} } @misc{MirskyKrauseHeckmann, author = {Mirsky, Vladimir M. and Krause, Christian and Heckmann, Klaus Dietrich}, title = {Capacitive detection of adsorption/desorption on hydrophobized gold electrodes: an application for surfactants adsorption and phospholipase assay}, series = {Chimica Chronica, New Series}, volume = {25}, journal = {Chimica Chronica, New Series}, pages = {179 -- 194}, language = {en} } @misc{KrauseMirskyHeckmann, author = {Krause, Christian and Mirsky, Vladimir M. and Heckmann, Klaus Dietrich}, title = {Capacitive detection of surfactant adsorption on hydrophobized gold electrodes}, series = {Langmuir}, volume = {12}, journal = {Langmuir}, number = {25}, issn = {0743-7463}, doi = {10.1021/la9601869}, pages = {6059 -- 6064}, abstract = {Nonspecific adsorption of surfactants on polycrystalline gold electrodes, covered by a chemically adsorbed monomolecular layer of octadecanethiol, was studied by means of capacitive measurements. Homologous series of fatty acids (from decane to tetradecane acids) and dodecanepyridinium chloride were used as surfactants. The behavior of the electrode was completely different in the first and subsequent cycles of adsorption/desorption. In the first adsorption cycle, an initial capacitance jump at low concentrations (<10 μM) occurs, while later the curves show the usual saturation behavior. The first surfactant layer could not be completely desorbed; only the electrode capacitance shown after the jump was reached. Subsequent cycles do not reveal any capacitance jumps and were completely reversible. Adsorption curves in the series of monoalkyl acids are shifted according to the Traube rule. A comparison with the surfactant adsorption at the air/water interface has been done.}, language = {en} } @misc{MirskyKrauseHeckmann, author = {Mirsky, Vladimir M. and Krause, Christian and Heckmann, Klaus Dietrich}, title = {Capacitive sensor for lipolytic enzymes}, series = {Thin Solid Films}, volume = {284-285}, journal = {Thin Solid Films}, issn = {0040-6090}, doi = {10.1016/S0040-6090(95)08485-1}, pages = {939 -- 941}, abstract = {The preparation of the capacitive biosensor for monitoring the activity of enzymes (lipases, phospholipases, etc.) hydrolysing waterinsoluble substrates into water-soluble products is described. The sensor is based on a sandwich-like structure: Au/S(CH₂)₁₇CH₁/substrate/electrolyte. Hydrolysis of the substrate leads to the formation of water-soluble products and desorption of these compounds from the electrode. When the product formation is the rate-limiting step of this process, the desorption rate is determined by the enzyme activity. The desorption can be easily monitored as an increase of the electrode capacitance. By following this principle it was possible to develop a sensor monitoring phospholipase A₂ activity even at the 50 pg ml-1 level.}, language = {en} } @inproceedings{KrauseMeinbergKrebsetal., author = {Krause, Chris and Meinberg, Uwe and Krebs, Irene and Schlauer, Christian and Otto, Dierk}, title = {A Contribution To SPDM Strategies In Aerospace}, series = {NAFEMS SPDM World Congress Stockholm 2017, Summary of proceedings}, booktitle = {NAFEMS SPDM World Congress Stockholm 2017, Summary of proceedings}, isbn = {978-1-910643-37-2}, pages = {S. 157}, abstract = {Long product lifecycles are standard in aerospace, thus simulation data must be handled. This data is critical because it represents real value for the enterprise. Furthermore, simulation data is created in lengthy business processes and often ends in large files. This sets challenges for handling it to allow an efficient storage approach but also full traceability. This paper is an interim result of the research projects VITIV (project number: 80164702) and the ProFIT-Programme supported by the federal state of Brandenburg and the European Union. Initially, the status quo must be analysed. Therefore, the current development processes to develop engine parts were investigated. The focus is the data created by analysts but for this task, all input data created prior must be known, handled and stored as well. Additionally, a new modular data structure is developed to fulfil the aforementioned requirements. However, two concepts for storing must be compared. The first would be to store all input files and boundary conditions separately without storing a full executable simulation file. This approach requires the functionality to automatically rebuild the executable file which takes time but provides a lean and modular storage. The other method would be to store the large runnable file and avoid protracted processes to rebuild the file. In some cases such rebuilding could last for several weeks. In this case, traceability must be secured. Currently, not all data regarding CAE is stored in the PLM system. The reasons differ from constraints in terms of configuration of the system, as well as a lack in foresight. This means that some process actors are focussed on a fast way to store their data but do not take into consideration that these objects must be found and used for investigations in the future. The next step will be to work on the process automation. These workflows should reduce the amount of manual user interactions, hence to speed up the processes and avoid sources of error. Furthermore, the developed method for storing the data has to reach the next level: from the secured test environment into a pre-production system.}, language = {en} } @misc{MirskyRieplKrauseetal., author = {Mirsky, Vladimir M. and Riepl, Michael and Krause, Christian and Novotny, Ivan and Splonskowski, Markus and Rehacek, Vlastimil and Tvarozek, Vladimir and Hummel, Helmut and Wolfbeis, Otto S.}, title = {Thin film electrodes for capacitive chemo- and biosensors: an optimization of the electrodes geometry}, series = {Materials Science Forum}, volume = {287-288}, journal = {Materials Science Forum}, issn = {1662-9752}, doi = {10.4028/www.scientific.net/MSF.287-288.423}, pages = {423 -- 426}, language = {en} } @inproceedings{ZiemsTannertTillmannetal., author = {Ziems, Christian and Tannert, Daniel and Tillmann, Christine and Kr{\"u}ger, Perco and Krause, S. and Krautz, Hans Joachim}, title = {Untersuchungen zur fortschrittlichen alkalischen Druckelektrolyse am Wasserstoff-Forschungszentrum Cottbus}, language = {de} }