TY - JOUR A1 - Miyamoto, Ko-ichiro A1 - Wagner, Torsten A1 - Yoshinobu, Tatsuo A1 - Kanoh, Shin`ichiro A1 - Schöning, Michael Josef T1 - Phase-mode LAPS and its application to chemical imaging JF - Sensors and Actuators B: Chemical. 154 (2011), H. 1 Y1 - 2011 SN - 1873-3077 SP - 28 EP - 32 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Buniatyan, Vahe V. A1 - Abouzar, Maryam H. A1 - Martirosyan, Norayr W. A1 - Schubert, Jürgen A1 - Gevorgian, Spartak A1 - Schöning, Michael Josef A1 - Poghossian, Arshak T1 - pH-sensitive properties of barium strontium titanate (BST) thin films prepared by pulsed laser deposition technique JF - Physica Status Solidi (A). 207 (2010), H. 4 Y1 - 2010 SN - 1862-6300 N1 - Special Issue: Engineering of Functional Interfaces EnFI 2009 SP - 824 EP - 830 ER - TY - JOUR A1 - Christiaens, P. A1 - Abouzar, Maryam H. A1 - Poghossian, Arshak A1 - Wagner, Torsten A1 - Bijnens, N. A1 - Williams, O. A. A1 - Daenen, M. A1 - Haenen, K. A1 - Douthéret, O. A1 - Haen, J. d´ A1 - Mekhalif, Z. A1 - Schöning, Michael Josef A1 - Wagner, P. T1 - pH sensitivity of nanocrystalline diamond films JF - Physica status solidi (A). 204 (2007), H. 9 Y1 - 2007 SN - 0031-8965 SP - 2925 EP - 2930 ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Abouzar, Maryam H. A1 - Poghossian, Arshak T1 - pH and ion sensitivity of a field-effect EIS (electrolyte-insulator-semiconductor) sensor covered with polyelectrolyte multilayers JF - Journal of Solid State Electrochemistry. 13 (2009), H. 1 Y1 - 2009 SN - 1433-0768 N1 - This manuscript is an invited paper to the special issue on “Solid-state potentiometric sensors” (Guest editor: Johan Bobacka). SP - 115 EP - 122 ER - TY - JOUR A1 - Förster, Arnold A1 - Stock, J. A1 - Indlekofer, K. M. T1 - Perspectives of resonant tunneling diodes JF - Recent research developments in materials science & engineering/ 1,2 Y1 - 2002 SN - 81-7895-057-X N1 - Nebent.: Materials science & engineering SP - 527 EP - 556 PB - Transworld Research Network CY - Trivandrum, India ER - TY - JOUR A1 - Abouzar, Maryam H. A1 - Poghossian, Arshak A1 - Razavi, Arash A1 - Besmehn, Astrid A1 - Bijnens, Nathalie A1 - Williams, Oliver A. A1 - Haenen, Ken A1 - Wagner, Patrick A1 - Schöning, Michael Josef T1 - Penicillin detection with nanocrystalline-diamond field-effect sensor JF - physica status solidi (a). 205 (2008), H. 9 Y1 - 2008 SN - 1862-6319 N1 - Special Issue: Hasselt Diamond Workshop 2008 - SBDD XIII SP - 2141 EP - 2145 ER - 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 - http://dx.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 - Poghossian, Arshak A1 - Thust, M. A1 - Schroth, P. A1 - Steffen, A. A1 - Lüth, H. A1 - Schöning, Michael Josef T1 - Penicillin detection by means of silicon-based field-effect structures JF - Sensors and Materials. 13 (2001), H. 4 Y1 - 2001 SN - 0392-2510 SP - 207 EP - 223 ER - TY - JOUR A1 - Poghossian, Arshak A1 - Yoshinobu, Tatsuo A1 - Simonis, A. A1 - Ecken, H. A1 - Lüth, Hans A1 - Schöning, Michael Josef T1 - Penicillin detection by means of field-effect based sensors: EnFET, capacitive EIS sensor or LAPS? JF - Sensors and Actuators B. 78 (2001), H. 1-3 Y1 - 2001 SN - 0925-4005 SP - 237 EP - 242 ER - TY - JOUR A1 - Poghossian, Arshak A1 - Yoshinobu, T. A1 - Simonis, A. A1 - Ecken, H. A1 - Lüth, H. A1 - Schöning, Michael Josef T1 - Penicillin detection by means of field-effect based sensors: EnFET, capacitive EIS sensor or LAPS? JF - Proceedings : Copenhagen, Denmark, 27 - 30 August 2000 / [ed.: R. de Reus ...] Y1 - 2000 SN - 87-89935-50-0 N1 - Eurosensors ; (14, 2000, København) ; Eurosensors ; (14 : ; 2000.08.27-30 : ; Copenhagen) ; European Conference on Solid-State Transducers ; (14 : ; 2000.08.27-30 : ; Copenhagen) SP - 27 EP - 30 PB - MIC, Mikroelektronik Centret CY - Lyngby, Denmark ER - TY - JOUR A1 - Siqueira, José R. Jr. A1 - Abouzar, Maryam H. A1 - Poghossian, Arshak A1 - Zucolotto, Valtencir A1 - Oliveira, Osvaldo N. Jr. A1 - Schöning, Michael Josef T1 - Penicillin biosensor based on a capacitive field-effect structure functionalized with a dendrimer/carbon nanotube multilayer JF - Biosensors and Bioelectronics. 25 (2009), H. 2 Y1 - 2009 SN - 0956-5663 SP - 497 EP - 501 ER - TY - JOUR A1 - Schmitt, G. A1 - Faßbender, F. A1 - Lüth, H. A1 - Schöning, Michael Josef A1 - Schultze, J. W. A1 - Buß, G. T1 - Passivation and corrosion of microelectrode arrays JF - Materials and Corrosion. 51 (2000), H. 1 Y1 - 2000 SN - 0947-5117 SP - 20 EP - 25 ER - TY - JOUR A1 - Gun, Jenny A1 - Rizkov, Dan A1 - Lev, Ovadia A1 - Abouzar, Maryam H. A1 - Poghossian, Arshak A1 - Schöning, Michael Josef T1 - Oxygen plasma-treated gold nanoparticle-based field-effect devices as transducer structures for bio-chemical sensing JF - Microchimica Acta. 164 (2008), H. 3-4 Y1 - 2008 SN - 1436-5073 SP - 395 EP - 404 ER - TY - JOUR A1 - Pita, Marcos A1 - Krämer, Melina A1 - Zouh, Jian A1 - Poghossian, Arshak A1 - Schöning, Michael Josef A1 - Fernandez, Victor M. A1 - Katz, Evgeny T1 - Optoelectronic Properties of Nanostructured Ensembles Controlled by Biomolecular Logic Systems JF - ACS Nano. 10 (2008), H. 2 Y1 - 2008 SN - 1936-086X SP - 2160 EP - 2166 ER - TY - JOUR A1 - Arreola, Julio A1 - Mätzkow, Malte A1 - Durán, Marlena Palomar A1 - Greeff, Anton A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Optimization of the immobilization of bacterial spores on glass substrates with organosilanes JF - Physica status solidi (A) : Applications and materials science N2 - Spores can be immobilized on biosensors to function as sensitive recognition elements. However, the immobilization can affect the sensitivity and reproducibility of the sensor signal. In this work, three different immobilization strategies with organosilanes were optimized and characterized to immobilize Bacillus atrophaeus spores on glass substrates. Five different silanization parameters were investigated: nature of the solvent, concentration of the silane, silanization time, curing process, and silanization temperature. The resulting silane layers were resistant to a buffer solution (e.g., Ringer solution) with a polysorbate (e.g., Tween®80) and sonication. KW - silanization KW - organosilanes KW - immobilization KW - endospores KW - biosensors KW - Bacillus atrophaeus Y1 - 2016 U6 - http://dx.doi.org/10.1002/pssa.201532914 SN - 1862-6319 VL - 213 IS - 6 SP - 1463 EP - 1470 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Degering, Christian A1 - Eggert, Thorsten A1 - Puls, Michael A1 - Bongaerts, Johannes A1 - Evers, Stefan A1 - Maurer, Karl-Heinz A1 - Jaeger, Karl-Erich T1 - Optimization of protease secretion in Bacillus subtilis and Bacillus licheniformis by screening of homologous and herologous signal peptides JF - Applied and environmental microbiology N2 - Bacillus subtilis and Bacillus licheniformis are widely used for the large-scale industrial production of proteins. These strains can efficiently secrete proteins into the culture medium using the general secretion (Sec) pathway. A characteristic feature of all secreted proteins is their N-terminal signal peptides, which are recognized by the secretion machinery. Here, we have studied the production of an industrially important secreted protease, namely, subtilisin BPN′ from Bacillus amyloliquefaciens. One hundred seventy-three signal peptides originating from B. subtilis and 220 signal peptides from the B. licheniformis type strain were fused to this secretion target and expressed in B. subtilis, and the resulting library was analyzed by high-throughput screening for extracellular proteolytic activity. We have identified a number of signal peptides originating from both organisms which produced significantly increased yield of the secreted protease. Interestingly, we observed that levels of extracellular protease were improved not only in B. subtilis, which was used as the screening host, but also in two different B. licheniformis strains. To date, it is impossible to predict which signal peptide will result in better secretion and thus an improved yield of a given extracellular target protein. Our data show that screening a library consisting of homologous and heterologous signal peptides fused to a target protein can identify more-effective signal peptides, resulting in improved protein export not only in the original screening host but also in different production strains. Y1 - 2010 U6 - http://dx.doi.org/10.1128/AEM.01146-10 SN - 1098-5336 (E-Journal); 0003-6919 (Print); 0099-2240 (Print) VL - 76 IS - 19 SP - 6370 EP - 6378 PB - American Society for Microbiology CY - Washington, DC ER - TY - JOUR A1 - Faßbender, F. A1 - Schmitt, G. A1 - Schöning, Michael Josef A1 - Lüth, H. A1 - Buß, G. A1 - Schultze, J. W. T1 - Optimization of passivation layers for corrosion protection of silicon-based microelectrode arrays JF - Sensors and Actuators B. 68 (2000), H. 1-3 Y1 - 2000 SN - 0925-4005 SP - 128 EP - 133 ER - TY - JOUR A1 - Dantism, Shahriar A1 - Röhlen, Desiree A1 - Wagner, Torsten A1 - Wagner, Patrick A1 - Schöning, Michael Josef T1 - Optimization of Cell-Based Multi-Chamber LAPS Measurements Utilizing FPGA-Controlled Laser-Diode Modules JF - physica status solidi a : applications and materials sciences N2 - A light-addressable potentiometric sensor (LAPS) is a field-effect-based potentiometric device, which detects concentration changes of an analyte solution on the sensor surface in a spatially resolved way. It uses a light source to generate electron–hole pairs inside the semiconductor, which are separated in the depletion region due to an applied bias voltage across the sensor structure and hence, a surface-potential-dependent photocurrent can be read out. However, depending on the beam angle of the light source, scattering effects can occur, which influence the recorded signal in LAPS-based differential measurements. To solve this problem, a novel illumination unit based on a field programmable gate array (FPGA) consisting of 16 small-sized tunable infrared laser-diode modules (LDMs) is developed. Due to the improved focus of the LDMs with a beam angle of only 2 mrad, undesirable scattering effects are minimized. Escherichia coli (E. coli) K12 bacteria are used as a test microorganism to study the extracellular acidification on the sensor surface. Furthermore, a salt bridge chamber is built up and integrated with the LAPS system enabling multi-chamber differential measurements with a single Ag/AgCl reference electrode. Y1 - 2018 U6 - http://dx.doi.org/10.1002/pssa.201800058 SN - 1862-6319 VL - 215 IS - 15 SP - Article number 1800058 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Pilas, Johanna A1 - Mariano, K. A1 - Keusgen, M. A1 - Selmer, Thorsten A1 - Schöning, Michael Josef T1 - Optimization of an Enzyme-based Multi-parameter Biosensor for Monitoring Biogas Processes JF - Procedia Engineering Y1 - 2015 U6 - http://dx.doi.org/10.1016/j.proeng.2015.08.702 SN - 1877-7058 N1 - Part of special issue "Eurosensors 2015" VL - 120 SP - 532 EP - 535 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Pilas, Johanna A1 - Yazici, Yasemen A1 - Selmer, Thorsten A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Optimization of an amperometric biosensor array for simultaneous measurement of ethanol, formate, d- and l-lactate JF - Electrochimica Acta N2 - The immobilization of NAD+-dependent dehydrogenases, in combination with a diaphorase, enables the facile development of multiparametric sensing devices. In this work, an amperometric biosensor array for simultaneous determination of ethanol, formate, d- and l-lactate is presented. Enzyme immobilization on platinum thin-film electrodes was realized by chemical cross-linking with glutaraldehyde. The optimization of the sensor performance was investigated with regard to enzyme loading, glutaraldehyde concentration, pH, cofactor concentration and temperature. Under optimal working conditions (potassium phosphate buffer with pH 7.5, 2.5 mmol L-1 NAD+, 2.0 mmol L-1 ferricyanide, 25 °C and 0.4% glutaraldehyde) the linear working range and sensitivity of the four sensor elements was improved. Simultaneous and cross-talk free measurements of four different metabolic parameters were performed successfully. The reliable analytical performance of the biosensor array was demonstrated by application in a clarified sample of inoculum sludge. Thereby, a promising approach for on-site monitoring of fermentation processes is provided. KW - Simultaneous determination KW - Enzymatic biosensor KW - Diaphorase KW - Dehydrogenase Y1 - 2017 U6 - http://dx.doi.org/10.1016/j.electacta.2017.07.119 SN - 0013-4686 VL - 251 SP - 256 EP - 262 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Kirchner, Patrick A1 - Oberländer, Jan A1 - Friedrich, Peter A1 - Berger, Jörg A1 - Suso, Henri-Pierre A1 - Kupyna, Andriy A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Optimisation and fabrication of a calorimetric gas sensor built up on a polyimide substrate for H2O2 monitoring JF - Physica status solidi (a) : applications and material science. 208 (2011), H. 6 Y1 - 2011 SN - 1862-6319 SP - 1235 EP - 1240 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Wagner, Torsten A1 - Beging, Stefan A1 - Rotter, L. A1 - Poghossian, Arshak A1 - Biselli, Manfred A1 - Zang, Werner A1 - Schöning, Michael Josef T1 - Online-Messsysteme für die automatisierte Charakterisierung von feldeffektbasierten Biosensoren JF - 8. Dresdner Sensor-Symposium : Sensoren für Umwelt, Klima und Sicherheit, Biosensoren und Biosysteme, Sensoren und Sensorsysteme für die Prozesstechnik, Trends in der Sensortechnik, Materialentwicklung für die Sensorik; 8. Dresdner Sensor-Symposium, 10. - 12. Dezember 2007, Dresden / Gerald Gerlach ... (Hg.) Y1 - 2007 SN - 978-3-940046-45-1 N1 - Dresdner Sensor-Symposium <8, 2007, Dresden> ; Dresdner Beiträge zur Sensorik ; 29 SP - 257 EP - 260 PB - TUDpress, Verl. der Wissenschaften CY - Dresden ER - TY - JOUR A1 - Zatko, B. A1 - Dubecký, F. A1 - Bohacek, P. A1 - Gombia, E. A1 - Frigeri, P. A1 - Mosca, R. A1 - Franchi, S. A1 - Huarn, J. A1 - Nescas, V. A1 - Sekacova, M. A1 - Förster, Arnold A1 - Kordos, P. T1 - On the spectrometric performance limit of radiation detectors based on semi-insulating GaAs JF - Nuclear instruments and methods in physics research, Section A. 531 (2004), H. 1-2 Y1 - 2004 SN - 0168-9002 SP - 111 EP - 120 ER - TY - JOUR A1 - Werner, Frederik A1 - Groebel, Simone A1 - Krumbe, Christoph A1 - Wagner, Torsten A1 - Selmer, Thorsten A1 - Yoshinobu, Tatsuo A1 - Baumann, Marcus A1 - Schöning, Michael Josef T1 - Nutrient concentration-sensitive microorganism-based biosensor JF - Physica Status Solidi (a) Y1 - 2012 U6 - http://dx.doi.org/10.1002/pssa.201100801 SN - 1862-6319 VL - 209 IS - 5 SP - 900 EP - 904 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Iken, Heiko A1 - Kirsanov, D. A1 - Legin, A. A1 - Schöning, Michael Josef T1 - Novel Thin-Film Polymeric Materials for the Detection of Heavy Metals JF - Procedia Engineering N2 - A variety of transition metals, e.g., copper, zinc, cadmium, lead, etc. are widely used in industry as components for wires, coatings, alloys, batteries, paints and so on. The inevitable presence of transition metals in industrial processes implies the ambition of developing a proper analytical technique for their adequate monitoring. Most of these elements, especially lead and cadmium, are acutely toxic for biological organisms. Quantitative determination of these metals at low activity levels in different environmental and industrial samples is therefore a vital task. A promising approach to achieve an at-side or on-line monitoring on a miniaturized and cost efficient way is the combination of a common potentiometric sensor array with heavy metal-sensitive thin-film materials, like chalcogenide glasses and polymeric materials, respectively. Y1 - 2012 U6 - http://dx.doi.org/10.1016/j.proeng.2012.09.148 SN - 1877-7058 N1 - Part of special issue "26th European Conference on Solid-State Transducers, EUROSENSOR 2012" IS - 47 SP - 322 EP - 325 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Haeger, Gerrit A1 - Jolmes, Tristan A1 - Oyen, Sven A1 - Jaeger, Karl-Erich A1 - Bongaerts, Johannes A1 - Schörken, Ulrich A1 - Siegert, Petra T1 - Novel recombinant aminoacylase from Paraburkholderia monticola capable of N-acyl-amino acid synthesis JF - Applied Microbiology and Biotechnology N2 - N-Acyl-amino acids can act as mild biobased surfactants, which are used, e.g., in baby shampoos. However, their chemical synthesis needs acyl chlorides and does not meet sustainability criteria. Thus, the identification of biocatalysts to develop greener synthesis routes is desirable. We describe a novel aminoacylase from Paraburkholderia monticola DSM 100849 (PmAcy) which was identified, cloned, and evaluated for its N-acyl-amino acid synthesis potential. Soluble protein was obtained by expression in lactose autoinduction medium and co-expression of molecular chaperones GroEL/S. Strep-tag affinity purification enriched the enzyme 16-fold and yielded 15 mg pure enzyme from 100 mL of culture. Biochemical characterization revealed that PmAcy possesses beneficial traits for industrial application like high temperature and pH-stability. A heat activation of PmAcy was observed upon incubation at temperatures up to 80 °C. Hydrolytic activity of PmAcy was detected with several N-acyl-amino acids as substrates and exhibited the highest conversion rate of 773 U/mg with N-lauroyl-L-alanine at 75 °C. The enzyme preferred long-chain acyl-amino-acids and displayed hardly any activity with acetyl-amino acids. PmAcy was also capable of N-acyl-amino acid synthesis with good conversion rates. The best synthesis results were obtained with the cationic L-amino acids L-arginine and L-lysine as well as with L-leucine and L-phenylalanine. Exemplarily, L-phenylalanine was acylated with fatty acids of chain lengths from C8 to C18 with conversion rates of up to 75%. N-lauroyl-L-phenylalanine was purified by precipitation, and the structure of the reaction product was verified by LC–MS and NMR. KW - Chaperone KW - Biocatalysis KW - Aminoacylase KW - Acylation KW - Acyl-amino acids KW - Biosurfactants Y1 - 2024 U6 - http://dx.doi.org/10.1007/s00253-023-12868-8 SN - 1432-0614 N1 - Corresponding author: Petra Siegert IS - 108 PB - Springer CY - Berlin ER - TY - JOUR A1 - Guo, Yuanyuan A1 - Seki, Kosuke A1 - Miyamoto, Ko-ichiro A1 - Wagner, Torsten A1 - Schöning, Michael Josef A1 - Yoshinobu, Tatsuo T1 - Novel photoexcitation method for light-addressable potentiometric sensor with higher spatial resolution JF - Applied physics express : APEX N2 - A novel photoexcitation method for the light-addressable potentiometric sensor (LAPS) is proposed to achieve a higher spatial resolution of chemical images. The proposed method employs a combined light source that consists of a modulated light probe, which generates the alternating photocurrent signal, and a ring of constant illumination surrounding it. The constant illumination generates a sheath of carriers with increased concentration which suppresses the spread of photocarriers by enhanced recombination. A device simulation was carried out to verify the effect of constant illumination on the spatial resolution, which demonstrated that a higher spatial resolution can be obtained. Y1 - 2014 U6 - http://dx.doi.org/10.7567/APEX.7.067301 SN - 1882-0786 (E-Journa); 1882-0778 (Print) VL - 7 IS - 6 SP - 067301-4 PB - IOP CY - Bristol ER - TY - CHAP A1 - Arida, Hassan A. A1 - Kloock, Joachim P. A1 - Schöning, Michael Josef T1 - Novel organic membrane-based thin-film microsensors for the determination of heavy metal cations N2 - A first step towards the fabrication and electrochemical evaluation of thin-film microsensors based on organic PVC membranes for the determination of Hg(II), Cd(II), Pb(II) and Cu(II) ions in solutions has been realised. The membrane-coating mixture used in the preparation of this new type of microsensors is incorporating PVC as supporting matrix, o-nitrophenyloctylether (o-NPOE) as solvent mediator and a recently synthesized Hg[dimethylglyoxime(phene)]2+ and Bis-(4-hydroxyacetophenone)-ethylenediamine as electroactive materials for Hg(II) and Cd(II), respectively. A set of three commercialised ionophores for Cd(II), Pb(II) and Cu(II) has been also used for comparison. Thin-film microsensors based on these membranes showed a Nernstian response of slope (26-30 mV/dec.) for the respective tested cations. The potentiometric response characteristics (linear range, pH range, detection limit and response time) are comparable with those obtained by conventional membranes as well as coated wire electrodes prepared from the same membrane. The realisation of the new organic membrane-based thin-film microsensors overcomes the problem of an insufficient selectivity of solid-state-based thinfilm sensors. KW - Biosensor KW - Heavy metal detection KW - thin-film microsensors KW - organic PVC membranes Y1 - 2006 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:a96-opus-1545 ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Malkoc, Ü. A1 - Thust, M. A1 - Steffen, A. A1 - Kordos, P. A1 - Lüth, H. T1 - Novel electrochemical sensors with structured and porous semiconductor/insulator capacitors JF - Sensors and Actuators B. 65 (2000), H. 1-3 Y1 - 2000 SN - 0925-4005 SP - 288 EP - 290 ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Lüth, H. T1 - Novel concepts for silicon-based biosensors JF - Physica Status Solidi (A) (2001) Y1 - 2001 SN - 0031-8965 SP - 65 EP - 77 ER - TY - JOUR A1 - Poghossian, Arshak A1 - Berndsen, Lars A1 - Lüth, Hans A1 - Schöning, Michael Josef T1 - Novel concepts for flow-rate and flow-direction determination by means of pH-sensitive ISFETs JF - Proceedings of SPIE. 4560 (2001) Y1 - 2001 SP - 19 EP - 27 ER - TY - JOUR A1 - Wagner, Torsten A1 - Miyamoto, Ko-ichiro A1 - Schöning, Michael Josef A1 - Yoshinobu, Tatsuo T1 - Novel combination of digital light processing (DLP) and light-addressable potentiometric sensors (LAPS) for flexible chemical imaging JF - Procedia Engineering. 5 (2010) Y1 - 2010 SN - 1877-7058 N1 - Eurosensor XXIV Conference SP - 520 EP - 523 ER - TY - JOUR A1 - Haeger, Gerrit A1 - Probst, Johanna A1 - Jaeger, Karl-Erich A1 - Bongaerts, Johannes A1 - Siegert, Petra T1 - Novel aminoacylases from Streptomyces griseus DSM 40236 and their recombinant production in Streptomyces lividans JF - FEBS Open Bio N2 - Amino acid-based surfactants are valuable compounds for cosmetic formulations. The chemical synthesis of acyl-amino acids is conventionally performed by the Schotten-Baumann reaction using fatty acyl chlorides, but aminoacylases have also been investigated for use in biocatalytic synthesis with free fatty acids. Aminoacylases and their properties are diverse; they belong to different peptidase families and show differences in substrate specificity and biocatalytic potential. Bacterial aminoacylases capable of synthesis have been isolated from Burkholderia, Mycolicibacterium, and Streptomyces. Although several proteases and peptidases from S. griseus have been described, no aminoacylases from this species have been identified yet. In this study, we investigated two novel enzymes produced by S. griseus DSM 40236ᵀ . We identified and cloned the respective genes and recombinantly expressed an α-aminoacylase (EC 3.5.1.14), designated SgAA, and an ε-lysine acylase (EC 3.5.1.17), designated SgELA, in S. lividans TK23. The purified aminoacylase SgAA was biochemically characterized, focusing on its hydrolytic activity to determine temperature- and pH optima and stabilities. The aminoacylase could hydrolyze various acetyl-amino acids at the Nα -position with a broad specificity regarding the sidechain. Substrates with longer acyl chains, like lauroyl-amino acids, were hydrolyzed to a lesser extent. Purified aminoacylase SgELA specific for the hydrolysis of Nε -acetyl-L-lysine was unstable and lost its enzymatic activity upon storage for a longer period but could initially be characterized. The pH optimum of SgELA was pH 8.0. While synthesis of acyl-amino acids was not observed with SgELA, SgAA catalyzed the synthesis of lauroyl-methionine. KW - Streptomyces lividans KW - recombinant expression KW - Streptomyces griseus KW - ε-lysine acylase KW - α-aminoacylase Y1 - 2023 U6 - http://dx.doi.org/10.1002/2211-5463.13723 SN - 2211-5463 N1 - Corresponding author: Petra Siegert VL - 13 IS - 12 SP - 2224 EP - 2238 PB - Wiley CY - Hoboken, NJ ER - TY - JOUR A1 - Karschuck, T. L. A1 - Filipov, Y. A1 - Bollella, P. A1 - Schöning, Michael Josef A1 - Katz, E. T1 - Not-XOR (NXOR) logic gate based on an enzyme-catalyzed reaction JF - International Journal of Unconventional Computing N2 - Enzyme-catalyzed reactions have been designed to mimic various Boolean logic gates in the general framework of unconventional biomolecular computing. While some of the logic gates, particularly OR, AND, are easy to realize with biocatalytic reactions and have been reported in numerous publications, some other, like NXOR, are very challenging and have not been realized yet with enzyme reactions. The paper reports on a novel approach to mimicking the NXOR logic gate using the bell-shaped enzyme activity dependent on pH values. Shifting pH from the optimum value to the acidic or basic values by using acid or base inputs (meaning 1,0 and 0,1 inputs) inhibits the enzyme reaction, while keeping the optimum pH (assuming 0,0 and 1,1 input combinations) preserves a high enzyme activity. The challenging part of the present approach is the selection of an enzyme with a well-demonstrated bell-shape activity dependence on the pH value. While many enzymes can satisfy this condition, we selected pyrroloquinoline quinone (PQQ)-dependent glucose dehydrogenase as this enzyme has the optimum pH center-located on the pH scale allowing the enzyme activity change by the acidic and basic pH shift from the optimum value corresponding to the highest activity. The present NXOR gate is added to the biomolecular “toolbox” as a new example of Boolean logic gates based on enzyme reactions. Y1 - 2019 SN - 1548-7199 VL - 14 IS - 3-4 SP - 235 EP - 242 PB - Old City Publishing CY - Philadelphia ER - TY - JOUR A1 - Arida, Hassan A. A1 - Al-haddad, Ameera A1 - Schöning, Michael Josef T1 - New Solid-State Organic Membrane Based Lead-Selective Micro-Electrode JF - International Journal of Electrochemical Science. 6 (2011), H. 9 Y1 - 2011 SN - 1452-3981 SP - 3858 EP - 3867 ER - TY - JOUR A1 - Falkenberg, Fabian A1 - Voß, Leonie A1 - Bott, Michael A1 - Bongaerts, Johannes A1 - Siegert, Petra T1 - New robust subtilisins from halotolerant and halophilic Bacillaceae JF - Applied Microbiology and Biotechnology N2 - The aim of the present study was the characterisation of three true subtilisins and one phylogenetically intermediate subtilisin from halotolerant and halophilic microorganisms. Considering the currently growing enzyme market for efficient and novel biocatalysts, data mining is a promising source for novel, as yet uncharacterised enzymes, especially from halophilic or halotolerant Bacillaceae, which offer great potential to meet industrial needs. Both halophilic bacteria Pontibacillus marinus DSM 16465ᵀ and Alkalibacillus haloalkaliphilus DSM 5271ᵀ and both halotolerant bacteria Metabacillus indicus DSM 16189 and Litchfieldia alkalitelluris DSM 16976ᵀ served as a source for the four new subtilisins SPPM, SPAH, SPMI and SPLA. The protease genes were cloned and expressed in Bacillus subtilis DB104. Purification to apparent homogeneity was achieved by ethanol precipitation, desalting and ion-exchange chromatography. Enzyme activity could be observed between pH 5.0–12.0 with an optimum for SPPM, SPMI and SPLA around pH 9.0 and for SPAH at pH 10.0. The optimal temperature for SPMI and SPLA was 70 °C and for SPPM and SPAH 55 °C and 50 °C, respectively. All proteases showed high stability towards 5% (w/v) SDS and were active even at NaCl concentrations of 5 M. The four proteases demonstrate potential for future biotechnological applications. KW - Biotechnological application KW - Bacillaceae KW - Subtilisin KW - Subtilases KW - Halotolerant protease Y1 - 2023 U6 - http://dx.doi.org/10.1007/s00253-023-12553-w SN - 1432-0614 N1 - Corresponding author: Petra Siegert VL - 107 SP - 3939 EP - 3954 PB - Springer Nature CY - Berlin ER - TY - JOUR A1 - Simonis, A. A1 - Lüth, H. A1 - Wang, J. A1 - Schöning, Michael Josef T1 - New concepts of miniaturised reference electrodes in silicon technology for potentiometric sensor systems JF - Sensors and Actuators B. 103 (2004), H. 1-2 Y1 - 2004 SN - 0925-4005 SP - 429 EP - 435 ER - TY - JOUR A1 - Werner, Frederik A1 - Spelthahn, H. A1 - Schöning, Michael Josef A1 - Krumbe, C. A1 - Wagner, Torsten A1 - Yoshinobu, T. A1 - Keusgen, M. T1 - Neue Ansteuerungselektronik für LAPS-basierte Biosensoren zur gleichzeitig ortsaufgelösten Messung der pH-Konzentration JF - Sensoren und Messsysteme 2010 [Elektronische Ressource] : Vorträge der 15. ITG/GMA-Fachtagung vom 18. bis 19. Mai 2010 in Nürnberg / Informationstechnische Gesellschaft im VDE (ITG); VDI/VDE-Gesellschaft Mess- und Automatisierungstechnik (GMA) Y1 - 2010 SN - 978-3-8007-3260-9 N1 - Fachtagung Sensoren und Messsysteme 15, 2010, Nürnberg ; Gesellschaft Mess- und Automatisierungstechnik SP - 109 EP - 114 PB - VDE Verlag CY - Berlin ER - TY - CHAP A1 - Schöning, Michael Josef A1 - Abdelghani, Adnane T1 - Nanoscale Science and Technology (NS&T’12) : Proceedings Book Humboldt Kolleg <2012, Tunisia> ; Tunisia, 17-19 March, 2012 / ed. by Michael J. Schöning ; Adnane Abdelghani N2 - Proceedings of the 2nd Humboldt Kolleg, Hammamet, Tunisia Organizer: Alexander von Humboldt Stiftung, Germany. pdf 184 p. Welcome Address Dear Participants, Welcome to the 2nd Humboldt Kolleg in “Nanoscale Science and Technology” (NS&T’12) in Tunisia, sponsored by the "Alexander von Humboldt" foundation. The NS&T’12 multidisciplinary scientific program includes seven "hot" topics dealing with "Nanoscale Science and Technology" covering basic and application-oriented research as well as industrial (market) aspects: - Molecular Biophyics, Spectroscopy Techniques, Imaging Microscopy - Nanomaterials Synthesis for Medicine and Bio-chemical Sensors - Nanostructures, Semiconductors, Photonics and Nanodevices - New Technologies in Market Industry - Environment, Electro-chemistry, Bio-polymers and Fuel Cells - Nanomaterials, Photovoltaic, Modelling, Quantum Physics - Microelectronics, Sensors Networks and Embedded Systems We are deeply indebted to all members of the Scientific Committee and General Chairs for joint Sessions and to all speakers and chairmen, who have dedicated invaluable time and efforts for the realization of this event. On behalf of the Organizing Committee, we are cordially inviting you to join the conference and hope that your stay will be fruitful, rewarding and enjoyable. Prof. Dr. Michael J. Schöning, Prof. Dr. Adnane Abdelghani KW - Biosensor KW - Nanotechnologie KW - Nanomaterial KW - Nano Materials KW - Bio-Sensors Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:a96-opus-3544 ER - TY - CHAP A1 - Poghossian, Arshak A1 - Weiland, Maryam A1 - Schöning, Michael Josef ED - Lvova, Larisa ED - Kirsanov, Dmitry ED - di Natale, Corrado ED - Legin, Audrey T1 - Nanoplate field-effect capacitors: a new transducer structure for multiparameter (bio-)chemical sensing T2 - Multisensor system for chemical analysis : materials and sensors N2 - An array of electrically isolated nanoplate field-effect silicon-on-insulator (SOI) capacitors as a new transducer structure for multiparameter (bio-)chemical sensing is presented. The proposed approach allows addressable biasing and electrical readout of multiple nanoplate field-effect capacitive (bio-)chemical sensors on the same SOI chip, as well as differential-mode measurements. The realized sensor chip has been applied for pH and penicillin concentration measurements, electrical monitoring of polyelectrolyte multilayer formation, and the label-free electrical detection of consecutive deoxyribonucleic acid (DNA) hybridization and denaturation events. Y1 - 2014 SN - 978-981-4411-15-8 ; 978-981-4411-16-5 U6 - http://dx.doi.org/10.1201/b15491-11 SP - 333 EP - 373 PB - Jenny Stanford Publishing CY - Singapore ET - 1 ER - TY - JOUR A1 - Abouzar, Maryam H. A1 - Ingebrandt, S. A1 - Poghossian, Arshak A1 - Zhang, Y. A1 - Vu, X. T. A1 - Moritz, W. A1 - Schöning, Michael Josef T1 - Nanoplate field-effect capacitive (bio-)chemical sensor array based on SOI structure JF - Procedia Chemistry. 1 (2009), H. 1 Y1 - 2009 SN - 1876-6196 N1 - Proceedings of the Eurosensors XXIII conference ; Eurosensors 23 SP - 670 EP - 673 ER - TY - JOUR A1 - Morais, Paulo V. A1 - Gomes, Vanderley F., Jr. A1 - Silva, Anielle C. A. A1 - Dantas, Noelio O. A1 - Schöning, Michael Josef A1 - Siqueira, José R., Jr. T1 - Nanofilm of ZnO nanocrystals/carbon nanotubes as biocompatible layer for enzymatic biosensors in capacitive field-effect devices JF - Journal of Materials Science N2 - The incorporation of nanomaterials that are biocompatible with different types of biological compounds has allowed the development of a new generation of biosensors applied especially in the biomedical field. In particular, the integration of film-based nanomaterials employed in field-effect devices can be interesting to develop biosensors with enhanced properties. In this paper, we studied the fabrication of sensitive nanofilms combining ZnO nanocrystals and carbon nanotubes (CNTs), prepared by means of the layer-by-layer (LbL) technique, in a capacitive electrolyte-insulator-semiconductor (EIS) structure for detecting glucose and urea. The ZnO nanocrystals were incorporated in a polymeric matrix of poly(allylamine) hydrochloride (PAH), and arranged with multi-walled CNTs in a LbL PAH-ZnO/CNTs film architecture onto EIS chips. The electrochemical characterizations were performed by capacitance–voltage and constant capacitance measurements, while the morphology of the films was characterized by atomic force microscopy. The enzymes glucose oxidase and urease were immobilized on film’s surface for detection of glucose and urea, respectively. In order to obtain glucose and urea biosensors with optimized amount of sensitive films, we investigated the ideal number of bilayers for each detection system. The glucose biosensor showed better sensitivity and output signal for an LbL PAH-ZnO/CNTs nanofilm with 10 bilayers. On the other hand, the urea biosensor presented enhanced properties even for the first bilayer, exhibiting high sensitivity and output signal. The presence of the LbL PAH-ZnO/CNTs films led to biosensors with better sensitivity and enhanced response signal, demonstrating that the adequate use of nanostructured films is feasible for proof-of-concept biosensors with improved properties that may be employed for biomedical applications. Y1 - 2017 U6 - http://dx.doi.org/10.1007/s10853-017-1369-y SN - 1573-4803 VL - 52 IS - 20 SP - 12314 EP - 12325 PB - Springer CY - Berlin ER - TY - JOUR A1 - Poghossian, Arshak A1 - Abouzar, Maryam H. A1 - Razavi, A. A1 - Bäcker, Matthias A1 - Bijnens, N. A1 - Williams, O. A. A1 - Haenen, K. A1 - Moritz, W. A1 - Wagner, P. A1 - Schöning, Michael Josef T1 - Nanocrystalline-diamond thin films with high pH and penicillin sensitivity prepared on a capacitive Si–SiO2 structure JF - Electrochimica Acta. 54 (2009), H. 25 Y1 - 2009 SN - 0013-4686 SP - 5981 EP - 5985 ER - TY - JOUR A1 - Christiaens, P. A1 - Abouzar, Maryam H. A1 - Poghossian, Arshak A1 - Wagner, Torsten A1 - Bijnens, N. A1 - Williams, O. A. A1 - Daenen, M. A1 - Haenen, K. A1 - Schöning, Michael Josef A1 - Wagner, P. T1 - Nanocrystalline diamond-based field-effect capacitive pH sensor JF - Transducers '07 Eurosensors XXI : digest of technical papers ; the14th International Conference on Solid-State Sensors, Actuators and Microsystems, June 10-14, 2007, Lyon, France / Gilles Delapierre (Ed.) Y1 - 2007 SN - 1-4244-0841-5 N1 - Eurosensors 21, 2007, Lyon ; International Conference on Solid-State Sensors, Actuators and Microsystems 14, 2007, Lyon SP - 1891 EP - 1894 PB - IEEE CY - Piscataway ER - TY - JOUR A1 - Poghossian, Arshak A1 - Abouzar, Maryam H. A1 - Christiaens, P. A1 - Williams, O. A. A1 - Haenen, K. A1 - Wagner, P. A1 - Schöning, Michael Josef T1 - Nanocrystalline diamond-based field-effect (bio-)chemical sensor JF - 8. Dresdner Sensor-Symposium : Sensoren für Umwelt, Klima und Sicherheit, Biosensoren und Biosysteme, Sensoren und Sensorsysteme für die Prozesstechnik, Trends in der Sensortechnik, Materialentwicklung für die Sensorik; 8. Dresdner Sensor-Symposium, 10. - 12. Dezember 2007, Dresden / Gerald Gerlach ... (Hg.) Y1 - 2007 SN - 978-3-940046-45-1 N1 - Dresdner Sensor-Symposium <8, 2007, Dresden> ; Dresdner Beiträge zur Sensorik ; 29 SP - 191 EP - 194 PB - TUDpress, Verl. der Wissenschaften CY - Dresden ER - TY - JOUR A1 - Schroth, P. A1 - Schöning, Michael Josef A1 - Schütz, S. A1 - Steffen, A. A1 - Weißbecker, B. A1 - Hummel, Hans E. A1 - Kordos, P. A1 - Lüth, H. T1 - Nachweis von organischen Duftstoffen durch Biosensoren auf der Basis von Insektenantennen JF - Gesellschaft Mess- und Automatisierungstechnik: Sensoren und Meßsysteme 2000 : Tagung Ludwigsburg, 13. und 14. März 2000 / VDI/VDE-Gesellschaft Meß- und Automatisierungstechnik Y1 - 2000 SN - 3-18-091530-7 N1 - VDI-Berichte; 1530 SP - 107 EP - 114 PB - VDI-Verl. CY - Düsseldorf: ER - TY - JOUR A1 - Khaydukova, M. M. A1 - Zadorozhnaya, O. A. A1 - Kirsanov, D. O. A1 - Iken, Heiko A1 - Rolka, David A1 - Schöning, Michael Josef A1 - Babain, V. A. A1 - Vlasov, Yu. G. A1 - Legin, A. V. T1 - Multivariate processing of atomic-force microscopy images for detection of the response of plasticized polymeric membranes JF - Russian journal of applied chemistry N2 - The possibility of using the atomic-force microscopy as a method for detection of the analytical signal from plasticized polymeric sensor membranes was analyzed. The surfaces of cadmium-selective membranes based on two polymeric matrices were examined. The digital images were processed with multivariate image analysis techniques. A correlation was found between the surface profile of an ion-selective membrane and the concentration of the ion in solution. Y1 - 2014 U6 - http://dx.doi.org/10.1134/S1070427214030112 SN - 1608-3296 (E-Journal); 1070-4272 (Print) VL - 87 IS - 3 SP - 307 EP - 314 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Karschuck, Tobias A1 - Schmidt, Stefan A1 - Achtsnicht, Stefan A1 - Poghossian, Arshak A1 - Wagner, Patrick A1 - Schöning, Michael Josef T1 - Multiplexing system for automated characterization of a capacitive field-effect sensor array JF - Physica Status Solidi A N2 - In comparison to single-analyte devices, multiplexed systems for a multianalyte detection offer a reduced assay time and sample volume, low cost, and high throughput. Herein, a multiplexing platform for an automated quasi-simultaneous characterization of multiple (up to 16) capacitive field-effect sensors by the capacitive–voltage (C–V) and the constant-capacitance (ConCap) mode is presented. The sensors are mounted in a newly designed multicell arrangement with one common reference electrode and are electrically connected to the impedance analyzer via the base station. A Python script for the automated characterization of the sensors executes the user-defined measurement protocol. The developed multiplexing system is tested for pH measurements and the label-free detection of ligand-stabilized, charged gold nanoparticles. KW - Capacitive field-effect sensor KW - Gold nanoparticles KW - Label-free detection KW - Multicell KW - Multiplexing Y1 - 2023 U6 - http://dx.doi.org/10.1002/pssa.202300265 SN - 1862-6300 (Print) SN - 1862-6319 (Online) N1 - Corresponding author: Michael Josef Schöning VL - 220 IS - 22 PB - Wiley-VCH CY - Weinheim ER - TY - THES A1 - Achtsnicht, Stefan T1 - Multiplex-Magnetdetektion von superparamagnetischen Beads zur Identifizierung von Trinkwasserkontaminationen N2 - Die qualitative und quantitative Detektion von Zielsubstanzen innerhalb einer wässrigen Probe ist für viele Fragestellungen von Interesse, etwa bei der Detektion von Kontaminationen in Trinkwasser in Krisensituationen. Hierbei ist es nicht nur wichtig, dass Pathogene möglichst sensitiv detektiert werden können, sondern auch, dass die Analyse schnell erfolgt, um Betroffenen im Katastrophenfall zügig sicheres Trinkwasser zu Verfügung stellen zu können. Da bei einem solchen Szenario nicht von einer in der Nähe befindlichen funktionierenden Laborinfrastruktur ausgegangen werden kann, ist es wichtig, dass die Messung direkt vor Ort erfolgen kann. Im Rahmen dieser Arbeit wurde untersucht, ob eine derartige Schnellanalytik mithilfe von superparamagnetischen Beads (MBs) und der magnetischen Frequenzmischtechnik möglich ist. Dabei werden die MBs mit Hilfe von primären Antikörpern an die Zielsubstanz gebunden und mit sekundären Antikörpern an die Poren-Oberfläche eines Polyethylen-Filters fixiert (Sandwich-Immunoassay). So kann die Quantifizierung der Zielsubstanz auf eine magnetische Messung der immobilisierten MB-Marker zurückgeführt werden. Die magnetische Frequenzmischtechnik basiert auf der Anregung der Probe mit Magnetfeldern zweier verschiedener Frequenzen. Die durch die nichtlineare Magnetisierungsform der superparamagnetischen MBs entstehenden Mischfrequenzen werden typischerweise mithilfe einer zweistufigen Lock-in-Detektion analysiert (analoge Demodulation), die in einem Magnetreader als Handheldgerät realisiert wurde. Zusätzlich zu dieser Technik wurde das Prinzip der direkten Digitalisierung des gesamten Antwortsignals mit anschließender Fourier-Analyse der erzeugten Mischfrequenzen experimentell umgesetzt, um die Amplituden und Phasen mehrerer Mischfrequenzen simultan zu erfassen. Eine Möglichkeit zur Sensitivitätssteigerung ist die magnetische Aufkonzentration, indem vor der magnetischen Analyse eine Separation der MBs aus einem größeren Probenvolumen mittels magnetischem Feldgradienten durchgeführt wird. Zur Charakterisierung verschiedener kommerzieller MBs hinsichtlich ihrer magnetischen Separierbarkeit wurde ein Aufbau zur Messung ihrer magnetophoretischen Beweglichkeiten realisiert und ihre Geschwindigkeiten im Gradientenfeld mikroskopisch gemessen.Da eine Probe oftmals nicht nur auf eine einzige Zielsubstanz, sondern simultan auf mehrere verschiedene Pathogene hin untersucht werden soll, wurden verschiedene Ansätze entwickelt und getestet, die einen solchen multiparametrischen magnetischen Immunoassay ermöglichen. Einerseits wurde eine räumliche Separation der Bindungsbereiche für verschiedene Zielsubstanzen realisiert, die sequentiell ausgewertet werden können. Andererseits wurde die Unterscheidung von verschiedenen Zielsubstanzen anhand der Charakteristika der an sie gebundenen, verschieden funktionalisierten MB-Typen untersucht. Für eine solche Unterscheidung wurde zum einen die Anregefrequenz der magnetischen Frequenzmischtechnik während einer Messung variiert. Damit konnte gezeigt werden, dass sich verschiedene MB-Sorten anhand der Phase ihrer Frequenzmischsignale voneinander unterscheiden lassen. Weiterhin wurde gezeigt, dass sich der Signalverlauf einer binären Mischung zweier verschiedener MB-Typen als gradueller Übergang der Verläufe der beiden reinen MB-Lösungen ergibt. Eine weitere Analysemethode für einen multiparametrischen Immunoassay besteht darin, ein zusätzliches einstellbares statisches magnetisches Offsetfeld zu verwenden. Hierfür wurden mehrere Aufbauten auf Basis von Permanent- und Elektromagneten simuliert, konstruiert und charakterisiert. Mithilfe von Simulationen konnte gezeigt werden, dass eine auf diesem Verfahren beruhende Unterscheidung für MBs mit unterschiedlichen magnetischen Partikelmomenten möglich ist. Als direkte Anwendung des hier entwickelten Magnetreaders in Zusammenspiel mit der digitalen Demodulation wurde ein magnetischer Assay gegen die B-Untereinheit des Choleratoxins in Trinkwasser mit einem niedrigen Detektionslimit von 0,2 ng/ml demonstriert. N2 - The qualitative and quantitative detection of target substances in an aqueous sample is of interest for many questions, for example in the detection of contaminations in drinking water in crisis situations. It is not only important that pathogens can be detected with highest possible sensitivity, but also that the analysis is carried out quickly so that safe drinking water can be provided in the event of a disaster. During such a scenario one cannot rely on a functioning laboratory infrastructure nearby. Therefore it is important that the measurement can be carried out directly on site. Within the scope of this work, it was investigated whether such a quick analysis can be performed using superparamagnetic beads (MBs) and the magnetic frequency mixing technique. The MBs are bound to the target substance with the aid of primary antibodies and fixed to the pore surfaces of a polyethylene filter with secondary antibodies (sandwich immunoassay). The quantification of the target substance can thus be traced back to a magnetic measurement of the immobilized MB markers. The magnetic frequency mixing technique is based on the excitation of the sample with magnetic fields of two different frequencies. The mixing frequencies generated due to the non-linear shape of the magnetization of the superparamagnetic MBs are typically analyzed using a two-stage Lock-in detection (analog demodulation), which was implemented in a magnetic reader as a handheld device. In addition to this technique, the principle of direct digitization of the entire response signal with subsequent Fourier analysis of the generated mixing frequencies was experimentally implemented in order to simultaneously record the amplitudes and phases of several mixing frequencies. One possibility for increasing the sensitivity is magnetic concentration. In that case, the MBs are separated from a larger sample volume by means of a magnetic field gradient before the magnetic analysis. To characterize various commercial MBs with regard to their magnetic separability, a setup for measuring their magnetophoretic mobility was implemented and their velocities in the gradient field were measured with an optical microscope.Often, a sample has to be examined not only for a single target substance, but for several different pathogens simultaneously. Various approaches have been developed and tested which enable such a multiparametric magnetic immunoassay. On the one hand, a spatial separation of the binding areas for different target substances was realized, which can be evaluated sequentially. On the other hand, a distinction among different target substances based on the magnetic characteristics of their attached different MB types was examined. For this discrimination, the excitation frequency of the magnetic frequency mixing technology was varied during measurement. It is shown that different MB types can be distinguished from one another based on the phase of their frequency mixing signals. The signal curve of a binary mixture of two different MB types is obtained as a gradual transition of the curves of the two pure MB solutions. Another method of analysis for a multiparametric immunoassay is based on an additional adjustable static magnetic offset field. For this purpose, several setups based on permanent magnets and electromagnets were simulated, designed and characterized. The simulations show that a distinction based on this method is possible for MBs with different magnetic particle moments. As a direct application of the developed magnetic reader in conjunction with digital demodulation, a magnetic assay against the B subunit of cholera toxin in drinking water was demonstrated, and a low detection limit of 0.2 ng/ml was achieved. KW - Choleratoxin B KW - Trinkwassersicherheit KW - cholera toxin B KW - drinking water safety KW - magnetic frequency mixing technique Y1 - 2020 U6 - http://dx.doi.org/10.18154/RWTH-2020-12052 N1 - Dissertation, RWTH Aachen University, 2020 ER - TY - JOUR A1 - Pourshahidi, Ali Mohammad A1 - Achtsnicht, Stefan A1 - Nambipareechee, Mrinal Murali A1 - Offenhäusser, Andreas A1 - Krause, Hans-Joachim T1 - Multiplex detection of magnetic beads using offset field dependent frequency mixing magnetic detection JF - Sensors N2 - Magnetic immunoassays employing Frequency Mixing Magnetic Detection (FMMD) have recently become increasingly popular for quantitative detection of various analytes. Simultaneous analysis of a sample for two or more targets is desirable in order to reduce the sample amount, save consumables, and save time. We show that different types of magnetic beads can be distinguished according to their frequency mixing response to a two-frequency magnetic excitation at different static magnetic offset fields. We recorded the offset field dependent FMMD response of two different particle types at frequencies ƒ₁ + n⋅ƒ₂, n = 1, 2, 3, 4 with ƒ₁ = 30.8 kHz and ƒ₂ = 63 Hz. Their signals were clearly distinguishable by the locations of the extremes and zeros of their responses. Binary mixtures of the two particle types were prepared with different mixing ratios. The mixture samples were analyzed by determining the best linear combination of the two pure constituents that best resembled the measured signals of the mixtures. Using a quadratic programming algorithm, the mixing ratios could be determined with an accuracy of greater than 14%. If each particle type is functionalized with a different antibody, multiplex detection of two different analytes becomes feasible. KW - colorization KW - multiplex detection KW - frequency mixing magnetic detection KW - magnetic nanoparticles Y1 - 2021 U6 - http://dx.doi.org/10.3390/s21175859 SN - 1424-8220 N1 - This article belongs to the Special Issue "Advanced Nanomaterial-Based Sensors for Biomedical Applications" VL - 21 IS - 17 PB - MDPI CY - Basel ER - TY - JOUR A1 - Achtsnicht, Stefan A1 - Pourshahidi, Ali Mohammad A1 - Offenhäusser, Andreas A1 - Krause, Hans-Joachim T1 - Multiplex detection of different magnetic beads using frequency scanning in magnetic frequency mixing technique JF - Sensors N2 - In modern bioanalytical methods, it is often desired to detect several targets in one sample within one measurement. Immunological methods including those that use superparamagnetic beads are an important group of techniques for these applications. The goal of this work is to investigate the feasibility of simultaneously detecting different superparamagnetic beads acting as markers using the magnetic frequency mixing technique. The frequency of the magnetic excitation field is scanned while the lower driving frequency is kept constant. Due to the particles’ nonlinear magnetization, mixing frequencies are generated. To record their amplitude and phase information, a direct digitization of the pickup-coil’s signal with subsequent Fast Fourier Transformation is performed. By synchronizing both magnetic beads using frequency scanning in magnetic frequency mixing technique magnetic fields, a stable phase information is gained. In this research, it is shown that the amplitude of the dominant mixing component is proportional to the amount of superparamagnetic beads inside a sample. Additionally, it is shown that the phase does not show this behaviour. Excitation frequency scans of different bead types were performed, showing different phases, without correlation to their diverse amplitudes. Two commercially available beads were selected and a determination of their amount in a mixture is performed as a demonstration for multiplex measurements. KW - frequency mixing magnetic detection KW - magnetic sandwich immunoassay KW - multiparametric immunoassays Y1 - 2019 U6 - http://dx.doi.org/10.3390/s19112599 SN - 1424-8220 VL - 19 IS - 11 PB - MDPI CY - Basel ER - TY - JOUR A1 - Reisert, Steffen A1 - Geissler, H. A1 - Weiler, C. A1 - Wagner, P. A1 - Schöning, Michael Josef T1 - Multiple sensor-type system for monitoring the microbicidal effectiveness of aseptic sterilisation processes JF - Food control N2 - The present work describes a novel multiple sensor-type system for the real-time analysis of aseptic sterilisation processes employing gaseous hydrogen peroxide (H2O2) as a sterilant. The inactivation kinetics of Bacillus atrophaeus by gaseous H2O2 have been investigated by means of a methodical calibration experiment, taking into account the process variables H2O2 concentration, humidity and gas temperature. It has been found that the microbicidal effectiveness at H2O2 concentrations above 2% v/v is largely determined by the concentration itself, while at lower H2O2 concentrations, the gas temperature and humidity play a leading role. Furthermore, the responses of different types of gas sensors towards the influencing factors of the sterilisation process have been analysed within the same experiment. Based on a correlation established between the inactivation kinetics and the sensor responses, a calorimetric H2O2 sensor and a metal-oxide semiconductor (MOX) sensor have been identified as possible candidates for monitoring the microbicidal effectiveness of aseptic sterilisation processes employing gaseous H2O2. Therefore, two linear models that describe the relationship between sensor response and microbicidal effectiveness have been proposed. Y1 - 2015 U6 - http://dx.doi.org/10.1016/j.foodcont.2014.07.063 SN - 1873-7129 (E-Journal); 0956-7135 (Print) VL - 47 SP - 615 EP - 622 ER - TY - JOUR A1 - Huck, Christina A1 - Poghossian, Arshak A1 - Kerroumi, Iman A1 - Schusser, Sebastian A1 - Bäcker, Matthias A1 - Zander, Willi A1 - Schubert, Jürgen A1 - Buniatyan, Vahe V. A1 - Martirosyan, Norayr W. A1 - Wagner, Patrick A1 - Schöning, Michael Josef T1 - Multiparameter sensor chip with Barium Strontium Titanate as multipurpose material JF - Electroanalysis N2 - It is well known that biochemical and biotechnological processes are strongly dependent and affected by a variety of physico-chemical parameters such as pH value, temperature, pressure and electrolyte conductivity. Therefore, these quantities have to be monitored or controlled in order to guarantee a stable process operation, optimization and high yield. In this work, a sensor chip for the multiparameter detection of three physico-chemical parameters such as electrolyte conductivity, pH and temperature is realized using barium strontium titanate (BST) as multipurpose material. The chip integrates a capacitively coupled four-electrode electrolyte-conductivity sensor, a capacitive field-effect pH sensor and a thin-film Pt-temperature sensor. Due to the multifunctional properties of BST, it is utilized as final outermost coating layer of the processed sensor chip and serves as passivation and protection layer as well as pH-sensitive transducer material at the same time. The results of testing of the individual sensors of the developed multiparameter sensor chip are presented. In addition, a quasi-simultaneous multiparameter characterization of the sensor chip in buffer solutions with different pH value and electrolyte conductivity is performed. To study the sensor behavior and the suitability of BST as multifunctional material under harsh environmental conditions, the sensor chip was exemplarily tested in a biogas digestate. Y1 - 2014 U6 - http://dx.doi.org/10.1002/elan.201400076 SN - 1521-4109 (E-Journal); 1040-0397 (Print) VL - 26 IS - 5 SP - 980 EP - 987 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Schubert, J. A1 - Schöning, Michael Josef A1 - Mourzina, Y. G. A1 - Legin, A. V. A1 - Vlasov, Y. G. A1 - Zander, W. A1 - Lüth, H. T1 - Multicomponent thin films for electrochemical sensor applications prepared by pulsed laser deposition JF - Sensors and Actuators B. 76 (2001), H. 1-3 Y1 - 2001 SN - 0925-4005 SP - 327 EP - 330 ER - TY - JOUR A1 - Miyamoto, K. A1 - Wagner, Torsten A1 - Schöning, Michael Josef A1 - Yoshinobu, T. T1 - Multi-well structure for cell culture on the chemical imaging sensor Y1 - 2011 N1 - 2011 16th International Solid-State Sensors, Actuators and Microsystems Conference (TRANSDUCERS) , Date: 5-9 June 2011 SP - 2130 EP - 2132 PB - IEEE CY - New York ER - TY - JOUR A1 - Reisert, Steffen A1 - Schneider, Benno A1 - Geissler, Hanno A1 - Gompel, Matthias van A1 - Wagner, Patrick A1 - Schöning, Michael Josef T1 - Multi-sensor chip for the investigation of different types of metal oxides for the detection of H2O2 in the ppm range JF - physica status solidi (a) N2 - In this work, a multi-sensor chip for the investigation of the sensing properties of different types of metal oxides towards hydrogen peroxide in the ppm range is presented. The fabrication process and physical characterization of the multi-sensor chip are described. Pure SnO2 and WO3 as well as Pd- and Pt-doped SnO2 films are characterized in terms of their sensitivity to H2O2. The sensing films have been prepared by drop-coating of water-dispensed nano-powders. A physical characterization, including scanning electron microscopy and X-ray diffraction analysis of the deposited metal-oxide films, was done. From the measurements in hydrogen peroxide atmosphere, it could be shown, that all of the tested metal oxide films are suitable for the detection of H2O2 in the ppm range. The highest sensitivity and reproducibility was achieved using Pt-doped SnO2. Calibration plot of a SnO2, WO3, Pt-, and Pd-doped SnO2 gas sensor for H2O2 concentrations in the ppm range. Y1 - 2013 SN - 1862-6319 VL - 210 IS - 5 SP - 898 EP - 904 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Bäcker, Matthias A1 - Schusser, Sebastian A1 - Poghossian, Arshak A1 - Schöning, Michael Josef T1 - Multi-Parametererfassung mit siliziumbasiertem Sensorchip: Aus Drei mach Eins JF - GIT Labor-Fachzeitschrift Y1 - 2014 SN - 0016-3538 IS - 2 SP - 28 EP - 30 PB - Wiley ER - TY - JOUR A1 - Huck, Christina A1 - Poghossian, Arshak A1 - Bäcker, Matthias A1 - Reisert, Steffen A1 - Kramer, Friederike A1 - Begoyan, Vardges K. A1 - Buniatyan, Vahe V. A1 - Schöning, Michael Josef T1 - Multi-parameter sensing using high-k oxide of barium strontium titanate JF - Physica status solidi (a) N2 - High-k perovskite oxide of barium strontium titanate (BST) represents a very attractive multi-functional transducer material for the development of (bio-)chemical sensors. In this work, a Si-based sensor chip containing Pt interdigitated electrodes covered with a thin BST layer (485 nm) has been developed for multi-parameter chemical sensing. The chip has been applied for the contactless measurement of the electrolyte conductivity, the detection of adsorbed charged macromolecules (positively charged polyelectrolytes of polyethylenimine) and the concentration of hydrogen peroxide (H2O2) vapor. The experimental results of functional testing of individual sensors are presented. The mechanism of the BST sensitivity to charged polyelectrolytes and H2O2 vapor has been proposed and discussed. Y1 - 2015 U6 - http://dx.doi.org/10.1002/pssa.201431911 SN - 1862-6319 VL - 212 IS - 6 SP - 1259 PB - Wiley CY - Weinheim ER - TY - CHAP A1 - Näther, Niko A1 - Poghossian, Arshak A1 - Platen, J. A1 - Yoshinobu, T. A1 - Koudelka-Hep, M. A1 - Schöning, Michael Josef T1 - Multi-parameter sensing of both physical and (bio-)chemical quantities using the same transducer principle T2 - Biochemical sensing utilisation of micro- and nanotechnologies : Warsaw, [23rd - 26th] November 2005 / ed. by M. Mascini ... Y1 - 2006 SP - 172 EP - 181 CY - Warsaw ER - TY - JOUR A1 - Poghossian, Arshak A1 - Schultze, J. W. A1 - Schöning, Michael Josef T1 - Multi-parameter detection of (bio-)chemical and physical quantities using an identical transducer principle JF - Sensors and Actuators B. 91 (2003), H. 1-3 Y1 - 2003 SN - 0925-4005 SP - 83 EP - 91 ER - TY - CHAP A1 - Huck, Christina A1 - Poghossian, Arshak A1 - Buniatyan, V. A1 - Schöning, Michael Josef T1 - Multi-parameter detection for supporting monitoring and control of biogas processes in agriculture T2 - Sensoren und Messsysteme 2014 ; Beiträge der 17. GMA/ITG-Fachtagung vom 3. bis 4. Juni 2014 in Nürnberg. (ITG-Fachbericht ; 250) Y1 - 2014 SN - 978-3-8007-3622-5 SP - 1 EP - 5 PB - VDE-Verl. CY - Berlin ER - TY - JOUR A1 - Yoshinobu, T. A1 - Ermelenko, Y. A1 - Mourzina, Y. A1 - Schöning, Michael Josef A1 - Iwasaki, H. A1 - Vlasov, Y. T1 - Multi-component analysis based on the light-addressable potentiometric sensor (LAPS) JF - Proceedings : 11th international conference Sensor 2003; 13 - 15 May 2003, Exhibition Centre Nuremberg, Germany Y1 - 2003 N1 - Internationale Messe mit Kongress Sensor <11, 2003, Nürnberg> SP - 141 EP - 144 PB - AMA Service CY - Wunstorf ER - TY - JOUR A1 - Kirchner, Patrick A1 - Oberländer, Jan A1 - Suco, Henri-Pierre A1 - Rysstad, Gunnar A1 - Schöning, Michael Josef T1 - Monitoring the microbicidal effectiveness of gaseous hydrogen peroxide in sterilisation processes by means of a calorimetric gas sensor JF - Food control N2 - In the present work, a novel method for monitoring sterilisation processes with gaseous H2O2 in combination with heat activation by means of a specially designed calorimetric gas sensor was evaluated. Therefore, the sterilisation process was extensively studied by using test specimens inoculated with Bacillus atrophaeus spores in order to identify the most influencing process factors on its microbicidal effectiveness. Besides the contact time of the test specimens with gaseous H2O2 varied between 0.2 and 0.5 s, the present H2O2 concentration in a range from 0 to 8% v/v (volume percent) had a strong influence on the microbicidal effectiveness, whereas the change of the vaporiser temperature, gas flow and humidity were almost negligible. Furthermore, a calorimetric H2O2 gas sensor was characterised in the sterilisation process with gaseous H2O2 in a wide range of parameter settings, wherein the measurement signal has shown a linear response against the H2O2 concentration with a sensitivity of 4.75 °C/(% v/v). In a final step, a correlation model by matching the measurement signal of the gas sensor with the microbial inactivation kinetics was established that demonstrates its suitability as an efficient method for validating the microbicidal effectiveness of sterilisation processes with gaseous H2O2. KW - hydrogen peroxide KW - sterilisation KW - Bacillus atrophaeus KW - calorimetric gas sensor Y1 - 2012 U6 - http://dx.doi.org/10.1016/j.foodcont.2012.11.048 SN - 0956-7135 VL - 31 IS - 2 SP - 530 EP - 538 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Schusser, Sebastian A1 - Krischer, Maximillian A1 - Bäcker, Matthias A1 - Poghossian, Arshak A1 - Wagner, Patrick A1 - Schöning, Michael Josef T1 - Monitoring of the Enzymatically Catalyzed Degradation of Biodegradable Polymers by Means of Capacitive Field-Effect Sensors JF - Analytical Chemistry N2 - Designing novel or optimizing existing biodegradable polymers for biomedical applications requires numerous tests on the effect of substances on the degradation process. In the present work, polymer-modified electrolyte–insulator–semiconductor (PMEIS) sensors have been applied for monitoring an enzymatically catalyzed degradation of polymers for the first time. The thin films of biodegradable polymer poly(d,l-lactic acid) and enzyme lipase were used as a model system. During degradation, the sensors were read-out by means of impedance spectroscopy. In order to interpret the data obtained from impedance measurements, an electrical equivalent circuit model was developed. In addition, morphological investigations of the polymer surface have been performed by means of in situ atomic force microscopy. The sensor signal change, which reflects the progress of degradation, indicates an accelerated degradation in the presence of the enzyme compared to hydrolysis in neutral pH buffer media. The degradation rate increases with increasing enzyme concentration. The obtained results demonstrate the potential of PMEIS sensors as a very promising tool for in situ and real-time monitoring of degradation of polymers. Y1 - 2015 U6 - http://dx.doi.org/10.1021/acs.analchem.5b00617 SN - 1520-6882 VL - 87 IS - 13 SP - 6607 EP - 6613 PB - ACS Publications CY - Washington, DC ER - TY - JOUR A1 - Gasparyan, F.V. A1 - Vitusevich, S.A. A1 - Offenhäusser, A. A1 - Schöning, Michael Josef T1 - Modified charge fluctuation noise model for electrolyte-insulator-semiconductor devices JF - Modern Physics Letters B (MPLB). 25 (2011), H. 11 Y1 - 2011 SN - 0217-9849 SP - 831 EP - 840 PB - World Scientific Publ. CY - Singapur ER - TY - JOUR A1 - Molinnus, Denise A1 - Iken, Heiko A1 - Johnen, Anna Lynn A1 - Richstein, Benjamin A1 - Hellmich, Lena A1 - Poghossian, Arshak A1 - Knoch, Joachim A1 - Schöning, Michael Josef T1 - Miniaturized pH-Sensitive Field-Effect Capacitors with Ultrathin Ta₂O₅ Films Prepared by Atomic Layer Deposition JF - physica status solidi (a) applications and materials science N2 - Miniaturized electrolyte–insulator–semiconductor capacitors (EISCAPs) with ultrathin gate insulators have been studied in terms of their pH-sensitive sensor characteristics: three different EISCAP systems consisting of Al–p-Si–Ta2O5(5 nm), Al–p-Si–Si3N4(1 or 2 nm)–Ta2O5 (5 nm), and Al–p-Si–SiO2(3.6 nm)–Ta2O5(5 nm) layer structures are characterized in buffer solution with different pH values by means of capacitance–voltage and constant capacitance method. The SiO2 and Si3N4 gate insulators are deposited by rapid thermal oxidation and rapid thermal nitridation, respectively, whereas the Ta2O5 film is prepared by atomic layer deposition. All EISCAP systems have a clear pH response, favoring the stacked gate insulators SiO2–Ta2O5 when considering the overall sensor characteristics, while the Si3N4(1 nm)–Ta2O5 stack delivers the largest accumulation capacitance (due to the lower equivalent oxide thickness) and a higher steepness in the slope of the capacitance–voltage curve among the studied stacked gate insulator systems. KW - atomic layer deposition KW - capacitive field-effect sensors KW - pH sensors KW - ultrathin gate insulators Y1 - 2022 U6 - http://dx.doi.org/10.1002/pssa.202100660 SN - 1862-6319 VL - 219 IS - 8 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Näther, Niko A1 - Auger, V. A1 - Poghossian, Arshak A1 - Koudelka-Hep, M. T1 - Miniaturized flow-through cell with integrated capacitive EIS sensors fabricated at wafer level using Si and Su-8 technologies JF - Technical digest of the 10th International Meeting on Chemical Sensors, July 11 - 14, 2004, Tsukuba, Japan / Japan Association of Chemical Sensors Y1 - 2004 N1 - Chemical sensors ; 20.2004 Suppl. B. IMCS ; (10, 2004, Tsukuba) ; International Meeting on Chemical Sensors ; (10 : ; 2004.07.11-14 : ; Tsukuba) SP - 554 EP - 555 PB - Japan Association of Chemical Sensors CY - Fukuoka ER - TY - JOUR A1 - Miyamoto, Ko-ichiro A1 - Kaneko, Kazumi A1 - Matsuo, Akira A1 - Wagner, Torsten A1 - Kanoh, Shin`ichiro A1 - Schöning, Michael Josef A1 - Yoshinobu, Tatsuo T1 - Miniaturized chemical imaging sensor system using an OLED display panel JF - Procedia Engineering. 5 (2010) Y1 - 2010 SN - 1877-7058 N1 - Eurosensor XXIV Conference SP - 516 EP - 519 ER - TY - JOUR A1 - Miyamoto, Ko-ichiro A1 - Kaneko, Kazumi A1 - Matsuo, Akira A1 - Wagner, Torsten A1 - Kanoh, Shiníchiro A1 - Schöning, Michael Josef A1 - Yoshinobu, Tatsuo T1 - Miniaturized chemical imaging sensor system using an OLED display panel JF - Sensors and Actuators B: Chemical N2 - The chemical imaging sensor is a semiconductor-based chemical sensor that can visualize the two-dimensional distribution of specific ions or molecules in the solution. In this study, we developed a miniaturized chemical imaging sensor system with an OLED display panel as a light source that scans the sensor plate. In the proposed configuration, the display panel is placed directly below the sensor plate and illuminates the back surface. The measured area defined by illumination can be arbitrarily customized to fit the size and the shape of the sample to be measured. The waveform of the generated photocurrent, the current–voltage characteristics and the pH sensitivity were investigated and pH imaging with this miniaturized system was demonstrated. KW - LAPS KW - Light-addressable potentiometric sensor KW - Chemical imaging sensor KW - Organic light-emitting diode display Y1 - 2012 U6 - http://dx.doi.org/10.1016/j.snb.2011.02.029 SN - 0925-4005 N1 - Part of special issue "Eurosensors XXIV, 2010" VL - 170 SP - 82 EP - 87 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Yoshinobu, Tatsuo A1 - Miyamoto, Ko-Ichiro A1 - Wagner, Torsten A1 - Schöning, Michael Josef ED - Yamaguchi, Takami T1 - Miniaturized and high-speed chemical imaging systems T2 - Nano-Biomedical Engineering 2012. Proceedings of the Tohoku University Global Centre of Excellence Programme, Sakura Hall, Tohoku University, Sendai Japan, 5 – 6 March 2012 Y1 - 2012 U6 - http://dx.doi.org/10.1142/9781848169067_0045 SP - 386 EP - 395 PB - World Scientific CY - Singapur ER - TY - JOUR A1 - Simonis, A. A1 - Lüth, H. A1 - Wang, J. A1 - Schöning, Michael Josef T1 - Miniaturisierte Referenzelektroden in Siliziumtechnologie für elektrochemische Sensoranwendungen JF - Sensoren und Messsysteme 2004 : Tagung Ludwigsburg, 15. und 16. März 2004 / VDI-VDE-Gesellschaft Mess- und Automatisierungstechnik Y1 - 2004 SN - 3-18-091829-2 N1 - Auch erschienen als: VDI-Berichte ; 1829 SP - 847 EP - 850 PB - VDI CY - Düsseldorf ER - TY - JOUR A1 - Simonis, A. A1 - Dawgul, M. A1 - Lüth, H. A1 - Schöning, Michael Josef T1 - Miniaturised reference electrodes for field-effect sensors compatible to silicon chip technology JF - Electrochimica Acta. 51 (2005), H. 5 Y1 - 2005 SN - 0013-4686 U6 - http://dx.doi.org/10.1016/j.electacta.2005.04.063 SP - 930 EP - 937 ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Näther, Niko A1 - Auger, V. A1 - Poghossian, Arshak A1 - Koudelka-Hep, M. T1 - Miniaturised flow-through cell with integrated capacitive EIS sensor fabricated at wafer level using Si and SU-8 technologies JF - Sensors and Actuators B. 108 (2005), H. 1-2 Y1 - 2005 SN - 0925-4005 N1 - Proceedings of the Tenth International Meeting on Chemical Sensors — IMCS - 10 2004 SP - 986 EP - 992 ER - TY - CHAP A1 - Platen, Johannes A1 - Poghossian, Arshak A1 - Schöning, Michael Josef T1 - Microstructured Nanostructures – nanostructuring by means of conventional photolithography and layer-expansion technique N2 - A new and simple method for nanostructuring using conventional photolithography and layer expansion or pattern-size reduction technique is presented, which can further be applied for the fabrication of different nanostructures and nano-devices. The method is based on the conversion of a photolithographically patterned metal layer to a metal-oxide mask with improved pattern-size resolution using thermal oxidation. With this technique, the pattern size can be scaled down to several nanometer dimensions. The proposed method is experimentally demonstrated by preparing nanostructures with different configurations and layouts, like circles, rectangles, trapezoids, “fluidic-channel”-, “cantilever”- and meander-type structures. KW - Biosensor KW - Nanostructuring KW - layer expansion KW - pattern-size reduction KW - self-aligned patterning Y1 - 2006 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:a96-opus-1477 ER - TY - JOUR A1 - Poghossian, Arshak A1 - Ingebrandt, S. A1 - Yeung, C.-K. A1 - Offenhäusser, A. A1 - Schöning, Michael Josef T1 - Microsensors based on ion-sensitive field-effect transistors for biomedical applications JF - Biomedizinische Technik. 49 (2004), H. 2 Y1 - 2004 SN - 0932-4666 SP - 1036 EP - 1037 ER - TY - JOUR A1 - Leinhos, Marcel A1 - Schusser, Sebastian A1 - Bäcker, Matthias A1 - Poghossian, Arshak A1 - Schöning, Michael Josef T1 - Micromachined multi-parameter sensor chip for the control of polymer-degradation medium JF - Physica Status Solidi (A) : special issue on engineering and functional interfaces N2 - It is well known that the degradation environment can strongly influence the biodegradability and kinetics of biodegradation processes of polymers. Therefore, besides the monitoring of the degradation process, it is also necessary to control the medium in which the degradation takes place. In this work, a micromachined multi-parameter sensor chip for the control of the polymer-degradation medium has been developed. The chip combines a capacitive field-effect pH sensor, a four-electrode electrolyte-conductivity sensor and a thin-film Pt-temperature sensor. The results of characterization of individual sensors are presented. In addition, the multi-parameter sensor chip together with an impedimetric polymer-degradation sensor was simultaneously characterized in degradation solutions with different pH and electrolyte conductivity. The obtained results demonstrate the feasibility of the multi-parameter sensor chip for the control of the polymer-degradation medium. Y1 - 2014 U6 - http://dx.doi.org/10.1002/pssa.201330364 SN - 1521-396X (E-Journal); 1862-6319 (E-Journal); 0031-8965 (Print); 1862-6300 (Print) VL - 211 IS - 6 SP - 1346 EP - 1351 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Wagner, Torsten A1 - Miyamoto, Ko-ichiro A1 - Shigihara, Noriko A1 - Schöning, Michael Josef A1 - Yoshinobu, Tatsuo T1 - Microfluidic systems with free definable sensor spots by an integrated light-addressable potentiometric sensor JF - Procedia Engineering. 25 (2011) Y1 - 2011 SN - 1877-7058 N1 - EurosensorsXXV ; Proc. Eurosensors XXV, September 4-7, 2011, Athens, Greece SP - 791 EP - 794 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Bäcker, Matthias A1 - Raue, Markus A1 - Schusser, Sebastian A1 - Jeitner, C. A1 - Breuer, L. A1 - Wagner, P. A1 - Poghossian, Arshak A1 - Förster, Arnold A1 - Mang, Thomas A1 - Schöning, Michael Josef T1 - Microfluidic chip with integrated microvalves based on temperature- and pH-responsive hydrogel thin films JF - Physica Status Solidi (a) N2 - Two types of microvalves based on temperature-responsive poly(N-isopropylacrylamide) (PNIPAAm) and pH-responsive poly(sodium acrylate) (PSA) hydrogel films have been developed and tested. The PNIPAAm and PSA hydrogel films were prepared by means of in situ photopolymerization directly inside the fluidic channel of a microfluidic chip fabricated by combining Si and SU-8 technologies. The swelling/shrinking properties and height changes of the PNIPAAm and PSA films inside the fluidic channel were studied at temperatures of deionized water from 14 to 36 °C and different pH values (pH 3–12) of Titrisol buffer, respectively. Additionally, in separate experiments, the lower critical solution temperature (LCST) of the PNIPAAm hydrogel was investigated by means of a differential scanning calorimetry (DSC) and a surface plasmon resonance (SPR) method. Mass-flow measurements have shown the feasibility of the prepared hydrogel films to work as an on-chip integrated temperature- or pH-responsive microvalve capable to switch the flow channel on/off. Y1 - 2012 U6 - http://dx.doi.org/10.1002/pssa.201100763 SN - 1862-6319 VL - 209 IS - 5 SP - 839 EP - 845 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Arida, Hassan A1 - Mohsen, Q. A1 - Schöning, Michael Josef T1 - Microfabrication, characterization and analytical application of a new thin-film silver microsensor JF - Electrochimica Acta. 54 (2009), H. 13 Y1 - 2009 SN - 0013-4686 SP - 3543 EP - 3547 ER - TY - JOUR A1 - Schöning, Michael Josef T1 - Microelectronics contacts (bio-)chemistry – Semiconductor-based sensors JF - Biologi Italiani. 8 (2001) Y1 - 2001 SN - 0392-2510 SP - 5 EP - 10 ER - TY - JOUR A1 - Schmitt, G. A1 - Werner, C. A1 - Schöning, Michael Josef T1 - Microelectrochemical efficiency evaluation of inhibitors for CO2 corrosion of carbon steel under high shear stress gradients JF - Corrosion 2002. Conference Proceedings. NACExpo, 57th Annual Conference and Exhibition, Denver, US, Apr 7-11, 2002 Y1 - 2002 N1 - Paper 02280 SP - 1 EP - 11 PB - NACE International CY - Houston, Texas ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Schroth, P. A1 - Hummel, Hans E. A1 - Weißbecker, B. A1 - Lüth, H. A1 - Schütz, S. T1 - Microcsaled living bioelectronic systems – Coupling beetles to silicon transducers JF - Chemical and biological sensors and analytical methods : proceedings of the international symposium / Sensor, Physical Electrochemistry, and Organic and Biological Electrochemistry Divisions. Ed.: M. Butler Y1 - 2001 SN - 1-56677-351-2 N1 - International Symposium: Chemical and Biological Sensors and Analytical Methods ; (2 : 2001.) SP - 165 EP - 173 PB - Electrochemical Society CY - Pennington, NJ ER - TY - JOUR A1 - Kurowski, A. A1 - Schultze, J. A1 - Lüth, H. A1 - Schöning, Michael Josef T1 - Micro- and nanopatterning of sensor chips by means of macroporous silicon. JF - Sensors and Actuators B. 83 (2002), H. 1-3 Y1 - 2002 SN - 0925-4005 N1 - Selected Papers from TRANSDUCERS '01 EUROSENSORS XV SP - 123 EP - 128 ER - TY - JOUR A1 - Kurowski, A. A1 - Schultze, J.W. A1 - Lüth, H. A1 - Schöning, Michael Josef T1 - Micro- and nanopatterning of sensor chips by means of macroporous silicon JF - Transducers '01 Eurosensors XV : digest of technical papers / the 11th International Conference on Solid-State Sensors and Actuators, June 10-14, 2001, Munich, Germany. Ernst Obermeier (Ed.) Y1 - 2001 SN - 3-540-42150-5 N1 - Eurosensors (15, 2001, München) ; International Conference on Solid State Sensors and Actuators (11, 2001, München) SP - 640 EP - 643 PB - Springer CY - Berlin [u.a.] ER - TY - JOUR A1 - Schmidt, R. A1 - Tonnesmann, A. A1 - Förster, Arnold A1 - Grimm, M. A1 - Kordos, P. A1 - Lüth, H. T1 - Metamorphic InAlAs/InGaAs HEMT's on GaAs substrates using an InP buffer layer JF - 8th IEEE International Symposium on High Performance Electron Devices for Microwave and Optoelectronic Applications : EDMO 2000 ; [13 - 14 November 2000, University of Glasgow] / organised by Department of Electronics and Electrical Engineering, University of Glasgow, Glasgow Scotland. MTT/ED/AP/LEO Societies Joint Chapter, United Kingdom and Republic of Ireland Section. With technical co-sponsorship from IEEE Electron Device Society Y1 - 2000 SN - 0-7803-6550-X N1 - EDMO <8, 2000, Glasgow> ; University / Department of Electronics and Electrical Engineering ; IEEE catalog number 00TH8534 SP - 95 EP - 98 PB - IEEE Operations Center CY - Piscataway, NJ ER - TY - JOUR A1 - Wilming, Anja A1 - Begemann, Jens A1 - Kuhne, Stefan A1 - Regestein, Lars A1 - Bongaerts, Johannes A1 - Evers, Stefan A1 - Maurer, Karl-Heinz A1 - Büchs, Jochen T1 - Metabolic studies of γ-polyglutamic acid production in Bacillus licheniformis by small-scale continuous cultivations JF - Biochemical engineering journal Y1 - 2013 SN - 1873-295X (E-Journal); 1369-703X (Print) VL - Vol. 73 SP - 29 EP - 37 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Huck, Christina A1 - Schiffels, Johannes A1 - Herrera, Cony N. A1 - Schelden, Maximilian A1 - Selmer, Thorsten A1 - Poghossian, Arshak A1 - Baumann, Marcus A1 - Wagner, Patrick A1 - Schöning, Michael Josef T1 - Metabolic responses of Escherichia coli upon glucose pulses captured by a capacitive field-effect sensor JF - Physica Status Solidi (A) N2 - Living cells are complex biological systems transforming metabolites taken up from the surrounding medium. Monitoring the responses of such cells to certain substrate concentrations is a challenging task and offers possibilities to gain insight into the vitality of a community influenced by the growth environment. Cell-based sensors represent a promising platform for monitoring the metabolic activity and thus, the “welfare” of relevant organisms. In the present study, metabolic responses of the model bacterium Escherichia coli in suspension, layered onto a capacitive field-effect structure, were examined to pulses of glucose in the concentration range between 0.05 and 2 mM. It was found that acidification of the surrounding medium takes place immediately after glucose addition and follows Michaelis–Menten kinetic behavior as a function of the glucose concentration. In future, the presented setup can, therefore, be used to study substrate specificities on the enzymatic level and may as well be used to perform investigations of more complex metabolic responses. Conclusions and perspectives highlighting this system are discussed. Y1 - 2013 U6 - http://dx.doi.org/10.1002/pssa.201200900 SN - 0031-8965 VL - 210 IS - 5 SP - 926 EP - 931 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Krämer, Marco A1 - Bongaerts, Johannes A1 - Bovenberg, Roel A1 - Kremer, Susanne A1 - Müller, Ulrike A1 - Orf, Sonja A1 - Wubbolts, Marcel A1 - Raeven, Leon T1 - Metabolic engineering for microbial production of shikimic acid JF - Metabolic engineering Y1 - 2003 SN - 1096-7184 (E-Journal); 1096-7176 (Print) VL - Vol. 5 IS - Iss. 4 SP - 277 EP - 283 ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Poghossian, Arshak A1 - Schultze, Joachim W. T1 - Measuring seven parameters by two ISFET modules in a microcell set-up JF - Int. Journal of Computational Engineering Science. 4 (2003), H. 2 Y1 - 2003 SN - 1465-8763 SP - 257 EP - 260 ER - TY - JOUR A1 - Achtsnicht, Stefan A1 - Schönenborn, Kristina A1 - Offenhäusser, Andreas A1 - Krause, Hans-Joachim T1 - Measurement of the magnetophoretic velocity of different superparamagnetic beads JF - Journal of Magnetism and Magnetic Materials N2 - The movement of magnetic beads due to a magnetic field gradient is of great interest in different application fields. In this report we present a technique based on a magnetic tweezers setup to measure the velocity factor of magnetically actuated individual superparamagnetic beads in a fluidic environment. Several beads can be tracked simultaneously in order to gain and improve statistics. Furthermore we show our results for different beads with hydrodynamic diameters between 200 and 1000 nm from diverse manufacturers. These measurement data can, for example, be used to determine design parameters for a magnetic separation system, like maximum flow rate and minimum separation time, or to select suitable beads for fixed experimental requirements. KW - magnetophoretic velocity KW - superparamagnetic bead KW - magnetic tweezers KW - magnetic separation KW - magnetic actuation Y1 - 2019 U6 - http://dx.doi.org/10.1016/j.jmmm.2018.10.066 SN - 0304-8853 VL - 477 IS - 1 SP - 244 EP - 248 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Schöning, Michael Josef A1 - Abouzar, Maryam H. A1 - Han, Y. A1 - Ingebrandt, S. A1 - Offenhäusser, A. A1 - Poghossian, Arshak T1 - Markierungsfreie DNA-Detektion mit Silizium-Feldeffektsensoren – Messeffekte oder Artefakte? T2 - Sensoren und Mess-Systeme 2006 : Vorträge der 13. ITG/GMA-Fachtagung vom 13. bis 14.3.2006 in Freiburg/Breisgau Y1 - 2006 SN - 3-8007-2939-3 SP - 443 EP - 446 PB - VDE Verl. CY - Berlin ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Abouzar, Maryam H. A1 - Poghossian, Arshak A1 - Han, Yinhua A1 - Offenhäusser, Andreas A1 - Ingebrandt, Sven T1 - Markierungsfreie DNA-Detektion mit Silizium-Feldeffekt-Sensoren – Messeffekte oder Artefakte? JF - tm - Technisches Messen . 74 (2007), H. 9 Y1 - 2007 SN - 0171-8096 SP - 466 EP - 476 ER - TY - JOUR A1 - Rabehi, Amine A1 - Garlan, Benjamin A1 - Achtsnicht, Stefan A1 - Krause, Hans-Joachim A1 - Offenhäusser, Andreas A1 - Ngo, Kieu A1 - Neveu, Sophie A1 - Graff-Dubois, Stephanie A1 - Kokabi, Hamid T1 - Magnetic detection structure for Lab-on-Chip applications based on the frequency mixing technique JF - Sensors N2 - A magnetic frequency mixing technique with a set of miniaturized planar coils was investigated for use with a completely integrated Lab-on-Chip (LoC) pathogen sensing system. The system allows the detection and quantification of superparamagnetic beads. Additionally, in terms of magnetic nanoparticle characterization ability, the system can be used for immunoassays using the beads as markers. Analytical calculations and simulations for both excitation and pick-up coils are presented; the goal was to investigate the miniaturization of simple and cost-effective planar spiral coils. Following these calculations, a Printed Circuit Board (PCB) prototype was designed, manufactured, and tested for limit of detection, linear response, and validation of theoretical concepts. Using the magnetic frequency mixing technique, a limit of detection of 15 µg/mL of 20 nm core-sized nanoparticles was achieved without any shielding. KW - Lab-on-Chip KW - magnetic sensing KW - frequency mixing KW - superparamagnetic nanoparticles KW - magnetic beads Y1 - 2018 U6 - http://dx.doi.org/10.3390/s18061747 SN - 1424-8220 VL - 18 IS - 6 PB - MDPI CY - Basel ER - TY - JOUR A1 - Gasparyan, Ferdinand V. A1 - Poghossian, Arshak A1 - Vitusevich, Svetlana A. A1 - Petrychuk, Mykhaylo V. A1 - Sydoruk, Viktor A. A1 - Siqueira, José R. Jr. A1 - Oliveira, Osvaldo N. Jr. A1 - Offenhäusser, Andreas A1 - Schöning, Michael Josef T1 - Low-Frequency Noise in Field-Effect Devices Functionalized With Dendrimer/Carbon-Nanotube Multilayers JF - IEEE Sensors Journal. 11 (2011), H. 1 Y1 - 2011 SN - 1530-437X SP - 142 EP - 149 PB - IEEE CY - New York ER - TY - JOUR A1 - Gasparyan, F. V. A1 - Poghossian, Arshak A1 - Vitusevich, S. A. A1 - Petrychuk, M. V. A1 - Sydoruk, V. A. A1 - Surmalyan, A. V. A1 - Siqueira, J. R. A1 - Oliveira, O. N. A1 - Offenhäusser, A. A1 - Schöning, Michael Josef T1 - Low Frequency Noise In Electrolyte-Gate Field-Effect Devices Functionalized With Dendrimer/Carbon-Nanotube Multilayers JF - Noise and fluctuations : 20th International Conference on Noise and Fluctuations, ICNF 2009, Pisa, Italy, 14 - 19 June 2009 / ed. Massimo Macucci; Giovanni Basso Y1 - 2009 SN - 9780735406650 N1 - AIP conference proceedings ; 1129 ; International Conference on Noise and Fluctuations ; (20, 2009, Pisa) SP - 133 EP - 136 PB - American Inst. of Physics CY - Melville, NY ER - TY - CHAP A1 - Bohrn, Ulrich A1 - Stütz, Evamaria A1 - Fleischer, Maximilian A1 - Schöning, Michael Josef A1 - Wagner, Patrick T1 - Living cell-based gas sensor system for the detection of acetone in air Y1 - 2012 SN - 978-3-9813484-2-2 U6 - http://dx.doi.org/10.5162/IMCS2012/3.2.3 SP - 269 EP - 272 ER - TY - JOUR A1 - Ermelenko, Y. A1 - Yoshinobu, T. A1 - Mourzina, Y. A1 - Furuichi, K. A1 - Levichev, S. A1 - Vlasov, Y. A1 - Schöning, Michael Josef A1 - Iwasaki, H. T1 - Lithium sensor based on the laser scanning semiconductor transducer JF - Analytica Chimica Acta. 459 (2002), H. 1 Y1 - 2002 SN - 0378-4304 SP - 1 EP - 9 ER - TY - JOUR A1 - Schütz, S. A1 - Weißbecker, G. A1 - Schroth, P. A1 - Schöning, Michael Josef T1 - Linkage of inanimate structures to biological systems – smart materials in biological micro- nanosystems JF - Smart materials : proceedings of the 1st Caesarium, Bonn, November 17 - 19, 1999 / Karl-Heinz Hoffmann ed. Y1 - 2001 SN - 3-540-67957-X SP - 149 EP - 157 PB - Springer CY - Berlin [u.a.] ER - TY - CHAP A1 - Breuer, Lars A1 - Raue, Markus A1 - Mang, Thomas A1 - Schöning, Michael Josef A1 - Thoelen, Ronald A1 - Wagner, Torsten T1 - Light-stimulated hydrogel actuators with incorporated graphene oxide for microfluidic applications T2 - 12. Dresdner Sensor-Symposium 2015 Y1 - 2015 U6 - http://dx.doi.org/10.5162/12dss2015/P5.8 SP - 206 EP - 209 ER - TY - JOUR A1 - Breuer, Lars A1 - Raue, Markus A1 - Kirschbaum, M. A1 - Mang, Thomas A1 - Schöning, Michael Josef A1 - Thoelen, R. A1 - Wagner, Torsten T1 - Light-controllable polymeric material based on temperature-sensitive hydrogels with incorporated graphene oxide JF - Physica status solidi (a) N2 - Poly(N-isopropylacrylamide) (PNIPAAm) hydrogel films with incorporated graphene oxide (GO) were developed and tested as light-stimulated actuators. GO dispersions were synthesized via Hummers method and characterized toward their optical properties and photothermal energy conversion. The hydrogels were prepared by means of photopolymerization. In addition, the influence of GO within the hydrogel network on the lower critical solution temperature (LCST) was investigated by differential scanning calorimetry (DSC). The optical absorbance and the response to illumination were determined as a function of GO concentration for thin hydrogel films. A proof of principle for the stimulation with light was performed. Y1 - 2015 U6 - http://dx.doi.org/10.1002/pssa.201431944 SN - 1862-6319 VL - 212 IS - 6 SP - 1368 EP - 1374 PB - Wiley CY - Weinheim ER -