TY - JOUR A1 - Koch, Claudia A1 - Poghossian, Arshak A1 - Schöning, Michael Josef A1 - Wege, Christian T1 - Penicillin Detection by Tobacco Mosaic Virus-Assisted Colorimetric Biosensors JF - Nanotheranostics N2 - The presentation of enzymes on viral scaffolds has beneficial effects such as an increased enzyme loading and a prolonged reusability in comparison to conventional immobilization platforms. Here, we used modified tobacco mosaic virus (TMV) nanorods as enzyme carriers in penicillin G detection for the first time. Penicillinase enzymes were conjugated with streptavidin and coupled to TMV rods by use of a bifunctional biotin-linker. Penicillinase-decorated TMV particles were characterized extensively in halochromic dye-based biosensing. Acidometric analyte detection was performed with bromcresol purple as pH indicator and spectrophotometry. The TMV-assisted sensors exhibited increased enzyme loading and strongly improved reusability, and higher analysis rates compared to layouts without viral adapters. They extended the half-life of the sensors from 4 - 6 days to 5 weeks and thus allowed an at least 8-fold longer use of the sensors. Using a commercial budget-priced penicillinase preparation, a detection limit of 100 µM penicillin was obtained. Initial experiments also indicate that the system may be transferred to label-free detection layouts. Y1 - 2018 U6 - https://doi.org/10.7150/ntno.22114 SN - 2206-7418 VL - 2 IS - 2 SP - 184 EP - 196 PB - Ivyspring CY - Sydney ER - TY - JOUR A1 - Spietz, Peter A1 - Spröwitz, Tom A1 - Seefeldt, Patric A1 - Grundmann, Jan Thimo A1 - Jahnke, Rico A1 - Mikschl, Tobias A1 - Mikulz, Eugen A1 - Montenegro, Sergio A1 - Reershemius, Siebo A1 - Renger, Thomas A1 - Ruffer, Michael A1 - Sasaki, Kaname A1 - Sznajder, Maciej A1 - Tóth, Norbert A1 - Ceriotti, Matteo A1 - Dachwald, Bernd A1 - Macdonald, Malcolm A1 - McInnes, Colin A1 - Seboldt, Wolfgang A1 - Quantius, Dominik A1 - Bauer, Waldemar A1 - Wiedemann, Carsten A1 - Grimm, Christian D. A1 - Hercik, David A1 - Ho, Tra-Mi A1 - Lange, Caroline A1 - Schmitz, Nicole T1 - Paths not taken – The Gossamer roadmap’s other options JF - Advances in Space Research KW - Solar sail KW - Small spacecraft KW - DLR-ESTEC GOSSAMER roadmap for solar sailing KW - GOSSAMER-1 Y1 - 2021 U6 - https://doi.org/10.1016/j.asr.2021.01.044 SN - 0273-1177 VL - 67 IS - 9 SP - 2912 EP - 2956 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Beging, Stefan A1 - Mlynek, Daniela A1 - Hataihimakul, Sudkanung A1 - Poghossian, Arshak A1 - Baldsiefen, Gerhard A1 - Busch, Heinz A1 - Laube, Norbert A1 - Kleinen, Lisa A1 - Schöning, Michael Josef T1 - Field-effect calcium sensor for the determination of the risk of urinary stone formation JF - Sensors and Actuators B: Chemical N2 - Urinary stone formation has been evolved to a widespread disease during the last years. The reason for the formation of urinary stones are little crystals, mostly composed of calcium oxalate, which are formed in human kidneys. The early diagnosis of the risk for urinary stone formation of patients can be determined by the “Bonn-Risk-Index” method based on the potentiometric detection of the Ca2+-ion concentration and an optical determination of the triggered crystallisation of calcium oxalate in unprocessed urine. In this work, miniaturised capacitive field-effect EMIS (electrolyte-membrane-insulator-semiconductor) sensors have been developed for the determination of the Ca2+-ion concentration in human native urine. The Ca2+-sensitive EMIS sensors have been systematically characterised by impedance spectroscopy, capacitance–voltage and constant–capacitance method in terms of sensitivity, signal stability and response time in both CaCl2 solutions and in native urine. The obtained results demonstrate the suitability of EMIS sensors for the measurement of the Ca2+-ion concentration in native urine of patients. Y1 - 2010 U6 - https://doi.org/10.1016/j.snb.2008.12.012 SN - 0925-4005 N1 - 22nd International Conference on Eurosensors: Dresden, Germany, 7-10 September 2008 VL - 144 IS - 2 SP - 374 EP - 379 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Reisert, Steffen A1 - Henkel, Hartmut A1 - Schneider, Andreas A1 - Schäfer, Daniel A1 - Friedrich, Peter A1 - Berger, Jörg A1 - Schöning, Michael Josef T1 - Development of a handheld sensor system for the online measurement of hydrogen peroxide in aseptic filling systems JF - Physica Status Solidi (A) N2 - A handheld sensor system for the online measurement of hydrogen peroxide (H2O2) in aseptic sterilisation processes has been developed. It is based on a calorimetric-type gas sensor that consists of a differential set-up of two temperature sensors, of which one is catalytically activated and the second one is passivated and used as reference. The sensor principle relies in detecting a rise in temperature on the active sensor due to the exothermic reaction of H2O2 on the catalytic surface. To characterise the sensor system towards H2O2 sensitivity and other influencing factors, measurements have been carried out both at an experimental set-up and a manufacturer's sterilisation machine. Physical sensor characterisation was done by means of the optical microscopy. Y1 - 2010 U6 - https://doi.org/10.1002/pssa.200983304 SN - 1862-6300 N1 - Special Issue: Engineering of Functional Interfaces EnFI 2009 VL - 207 IS - 4 SP - 913 EP - 918 PB - Wiley-VCH CY - Berlin ER - TY - JOUR A1 - Miyamoto, Ko-ichiro A1 - Sugawara, Yuri A1 - Kanoh, Shin´ichiro A1 - Yoshinobu, Tatsuo A1 - Wagner, Torsten A1 - Schöning, Michael Josef T1 - Image correction method for the chemical imaging sensor JF - Sensors and Actuators B: Chemical N2 - The chemical imaging sensor is a semiconductor-based chemical sensor that can visualize the spatial distribution of chemical species. For the practical application of this sensor, artifacts in the chemical images due to defects of the semiconductor substrate and contamination of the sensing surface etc. have been a major problem. An image correction method was developed to eliminate the influence of nonuniformity of individual sensor plate. Y1 - 2010 U6 - https://doi.org/10.1016/j.snb.2008.10.069 SN - 0925-4005 N1 - 22nd International Conference on Eurosensors: Dresden, Germany, 7-10 September 2008 VL - 144 IS - 2 SP - 344 EP - 348 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Unden, Gottfried A1 - Becker, S. A1 - Bongaerts, Johannes A1 - Holighaus, G. A1 - Schirawski, Jan A1 - Six, Simon T1 - O2-sensing and O2-dependent gene regulation in facultatively anaerobic bacteria JF - Archives of microbiology Y1 - 1995 SN - 1432-072X (E-Journal); 0003-9276 (Print); 0302-8933 (Print) VL - Vol. 164 IS - Iss. 2 SP - 81 EP - 90 ER - TY - JOUR A1 - Hoffschmidt, Bernhard A1 - Becker, Manfred A1 - Fend, Thomas T1 - Theoretical and numerical investigation of flow stability in porous materials applied as volumetric solar receivers / M. Becker ; T. Fend ; B. Hoffschmidt ... JF - Solar energy. 80 (2006), H. 10 Y1 - 2006 SN - 0038-092X N1 - Solar Power and Chemical Energy Systems (SolarPACES’04) SP - 1241 EP - 1248 ER - TY - JOUR A1 - Unden, Gottfried A1 - Becker, S. A1 - Bongaerts, Johannes A1 - Schirawski, Jan A1 - Six, Simon T1 - Oxygen regulated gene expression in facultatively anaerobic bacteria JF - Antonie van Leeuwenhoek Y1 - 1994 SN - 0003-6072 (Print) ; 1572-9699 (online) VL - Vol. 66 IS - Iss. 1-3 SP - 3 EP - 22 ER - TY - JOUR A1 - Abouzar, Maryam H. A1 - Poghossian, Arshak A1 - Siqueira, José R. Jr. A1 - Oliveira, Osvaldo N. Jr. A1 - Moritz, Werner A1 - Schöning, Michael Josef T1 - Capacitive electrolyte-insulator-semiconductor structures functionalised with a polyelectrolyte/enzyme multilayer: New strategy for enhanced field-effect biosensing JF - Physica Status Solidi (A) N2 - A novel strategy for enhanced field-effect biosensing using capacitive electrolyte–insulator–semiconductor (EIS) structures functionalised with pH-responsive weak polyelectrolyte/enzyme or dendrimer/enzyme multilayers is presented. The feasibility of the proposed approach is exemplarily demonstrated by realising a penicillin biosensor based on a capacitive p-Si–SiO2 EIS structure functionalised with a poly(allylamine hydrochloride) (PAH)/penicillinase and a poly(amidoamine) dendrimer/penicillinase multilayer. The developed sensors response to changes in both the local pH value near the gate surface and the charge of macromolecules induced via enzymatic reaction, resulting in a higher sensitivity. For comparison, an EIS penicillin biosensor with adsorptively immobilised penicillinase has been also studied. The highest penicillin sensitivity of 100 mV/dec has been observed for the EIS sensor functionalised with the PAH/penicillinase multilayer. The lower and upper detection limit was around 20 µM and 10 mM, respectively. In addition, an incorporation of enzymes in a multilayer prepared by layer-by-layer technique provides a larger amount of immobilised enzymes per sensor area, reduces enzyme leaching effects and thus, enhances the biosensor lifetime (the loss of penicillin sensitivity after 2 months was 10–12%). Y1 - 2010 U6 - https://doi.org/10.1002/pssa.200983317 SN - 1862-6300 N1 - Special Issue: Engineering of Functional Interfaces EnFI 2009 VL - 207 IS - 4 SP - 884 EP - 890 PB - Wiley-VCH CY - Berlin ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Tsarouchas, D. A1 - Beckers, Leah A1 - Schubert, J. A1 - Zander, W. A1 - Kordoš, P. A1 - Lüth, Hans T1 - A highly long-term stable silicon-based pH sensor using pulsed laser deposition technique JF - Sensors and Actuators B. 35 (1996), H. 1-3 Y1 - 1996 SN - 0925-4005 SP - 228 EP - 233 ER -