TY - JOUR A1 - Aliazizi, Fereshteh A1 - Özsoylu, Dua A1 - Bakhshi Sichani, Soroush A1 - Khorshid, Mehran A1 - Glorieux, Christ A1 - Robbens, Johan A1 - Schöning, Michael Josef A1 - Wagner, Patrick T1 - Development and Calibration of a Microfluidic, Chip-Based Sensor System for Monitoring the Physical Properties of Water Samples in Aquacultures JF - Micromachines N2 - In this work, we present a compact, bifunctional chip-based sensor setup that measures the temperature and electrical conductivity of water samples, including specimens from rivers and channels, aquaculture, and the Atlantic Ocean. For conductivity measurements, we utilize the impedance amplitude recorded via interdigitated electrode structures at a single triggering frequency. The results are well in line with data obtained using a calibrated reference instrument. The new setup holds for conductivity values spanning almost two orders of magnitude (river versus ocean water) without the need for equivalent circuit modelling. Temperature measurements were performed in four-point geometry with an on-chip platinum RTD (resistance temperature detector) in the temperature range between 2 °C and 40 °C, showing no hysteresis effects between warming and cooling cycles. Although the meander was not shielded against the liquid, the temperature calibration provided equivalent results to low conductive Milli-Q and highly conductive ocean water. The sensor is therefore suitable for inline and online monitoring purposes in recirculating aquaculture systems. KW - chip-based sensor setup KW - aquaculture KW - microfluidics KW - impedance spectroscopy KW - thermometry KW - electrical conductivity of liquids Y1 - 2024 U6 - https://doi.org/10.3390/mi15060755 SN - 2072-666X N1 - This article belongs to the Special Issue "Multisensor Arrays" N1 - Corresponding author: Michael J. Schöning VL - 15 IS - 6 PB - MDPI CY - Basel ER - TY - JOUR A1 - Achtsnicht, Stefan A1 - Neuendorf, Christian A1 - Faßbender, Tobias A1 - Nölke, Greta A1 - Offenhäusser, Andreas A1 - Krause, Hans-Joachim A1 - Schröper, Florian T1 - Sensitive and rapid detection of cholera toxin subunit B using magnetic frequency mixing detection JF - Plos One N2 - Cholera is a life-threatening disease caused by the cholera toxin (CT) as produced by some Vibrio cholerae serogroups. In this research we present a method which directly detects the toxin’s B subunit (CTB) in drinking water. For this purpose we performed a magnetic sandwich immunoassay inside a 3D immunofiltration column. We used two different commercially available antibodies to capture CTB and for binding to superparamagnetic beads. ELISA experiments were performed to select the antibody combination. The beads act as labels for the magnetic frequency mixing detection technique. We show that the limit of detection depends on the type of magnetic beads. A nonlinear Hill curve was fitted to the calibration measurements by means of a custom-written python software. We achieved a sensitive and rapid detection of CTB within a broad concentration range from 0.2 ng/ml to more than 700 ng/ml. Y1 - 2019 U6 - https://doi.org/10.1371/journal.pone.0219356 SN - 1932-6203 VL - 14 IS - 7 PB - Plos CY - San Francisco ER - TY - JOUR A1 - Scheele, Sandra A1 - Oertel, Dan A1 - Bongaerts, Johannes A1 - Evers, Stefan A1 - Hellmuth, Hendrik A1 - Maurer, Karl-Heinz A1 - Bott, Michael A1 - Freudl, Roland T1 - Secretory production of an FAD cofactor-containing cytosolic enzyme (sorbitol–xylitol oxidase from Streptomyces coelicolor) using the twin-arginine translocation (Tat) pathway of Corynebacterium glutamicum JF - Microbial biotechnology Y1 - 2013 SN - 1751-7915 SP - 202 EP - 206 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Molinnus, Denise A1 - Muschallik, Lukas A1 - Gonzalez, Laura Osorio A1 - Bongaerts, Johannes A1 - Wagner, Torsten A1 - Selmer, Thorsten A1 - Siegert, Petra A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Development and characterization of a field-effect biosensor for the detection of acetoin JF - Biosensors and Bioelectronics N2 - A capacitive electrolyte-insulator-semiconductor (EIS) field-effect biosensor for acetoin detection has been presented for the first time. The EIS sensor consists of a layer structure of Al/p-Si/SiO₂/Ta₂O₅/enzyme acetoin reductase. The enzyme, also referred to as butane-2,3-diol dehydrogenase from B. clausii DSM 8716T, has been recently characterized. The enzyme catalyzes the (R)-specific reduction of racemic acetoin to (R,R)- and meso-butane-2,3-diol, respectively. Two different enzyme immobilization strategies (cross-linking by using glutaraldehyde and adsorption) have been studied. Typical biosensor parameters such as optimal pH working range, sensitivity, hysteresis, linear concentration range and long-term stability have been examined by means of constant-capacitance (ConCap) mode measurements. Furthermore, preliminary experiments have been successfully carried out for the detection of acetoin in diluted white wine samples. Y1 - 2018 U6 - https://doi.org/10.1016/j.bios.2018.05.023 VL - 115 SP - 1 EP - 6 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Schroeter, Rebecca A1 - Hoffmann, Tamara A1 - Voigt, Birgit A1 - Meyer, Hanna A1 - Bleisteiner, Monika A1 - Muntel, Jan A1 - Jürgen, Britta A1 - Albrecht, Dirk A1 - Becher, Dörte A1 - Lalk, Michael A1 - Evers, Stefan A1 - Bongaerts, Johannes A1 - Maurer, Karl-Heinz A1 - Putzer, Harald A1 - Hecker, Michael A1 - Schweder, Thomas A1 - Bremer, Erhard T1 - Stress responses of the industrial workhorse Bacillus licheniformis to osmotic challenges JF - PLoS ONE N2 - The Gram-positive endospore-forming bacterium Bacillus licheniformis can be found widely in nature and it is exploited in industrial processes for the manufacturing of antibiotics, specialty chemicals, and enzymes. Both in its varied natural habitats and in industrial settings, B. licheniformis cells will be exposed to increases in the external osmolarity, conditions that trigger water efflux, impair turgor, cause the cessation of growth, and negatively affect the productivity of cell factories in biotechnological processes. We have taken here both systems-wide and targeted physiological approaches to unravel the core of the osmostress responses of B. licheniformis. Cells were suddenly subjected to an osmotic upshift of considerable magnitude (with 1 M NaCl), and their transcriptional profile was then recorded in a time-resolved fashion on a genome-wide scale. A bioinformatics cluster analysis was used to group the osmotically up-regulated genes into categories that are functionally associated with the synthesis and import of osmostress-relieving compounds (compatible solutes), the SigB-controlled general stress response, and genes whose functional annotation suggests that salt stress triggers secondary oxidative stress responses in B. licheniformis. The data set focusing on the transcriptional profile of B. licheniformis was enriched by proteomics aimed at identifying those proteins that were accumulated by the cells through increased biosynthesis in response to osmotic stress. Furthermore, these global approaches were augmented by a set of experiments that addressed the synthesis of the compatible solutes proline and glycine betaine and assessed the growth-enhancing effects of various osmoprotectants. Combined, our data provide a blueprint of the cellular adjustment processes of B. licheniformis to both sudden and sustained osmotic stress. Y1 - 2014 U6 - https://doi.org/10.1371/journal.pone.0080956 SN - 1932-6203 VL - 8 IS - 11 PB - PLOS CY - San Francisco ER - TY - JOUR A1 - Voigt, Birgit A1 - Schroeter, Rebecca A1 - Jürgen, Britta A1 - Albrecht, Dirk A1 - Evers, Stefan A1 - Bongaerts, Johannes A1 - Maurer, Karl-Heinz A1 - Schweder, Thomas A1 - Hecker, Michael T1 - The response of Bacillus licheniformis to heat and ethanol stress and the role of the SigB regulon JF - Proteomics Y1 - 2013 SN - 1615-9861 (E-Journal); 1615-9853 (Print) VL - Vol. 13 IS - Iss. 14 SP - 2140 EP - 2146 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Handtke, Stefan A1 - Volland, Sonja A1 - Methling, Karen A1 - Albrecht, Dirk A1 - Becher, Dörte A1 - Nehls, Jenny A1 - Bongaerts, Johannes A1 - Maurer, Karl-Heinz A1 - Lalk, Michael A1 - Liesegang, Heiko A1 - Voigt, Birgit A1 - Daniel, Rolf A1 - Hecker, Michael T1 - Cell physiology of the biotechnological relevant bacterium Bacillus pumilus - An omics-based approach JF - Journal of Biotechnology N2 - Members of the species Bacillus pumilus get more and more in focus of the biotechnological industry as potential new production strains. Based on exoproteome analysis, B. pumilus strain Jo2, possessing a high secretion capability, was chosen for an omics-based investigation. The proteome and metabolome of B. pumilus cells growing either in minimal or complex medium was analyzed. In total, 1542 proteins were identified in growing B. pumilus cells, among them 1182 cytosolic proteins, 297 membrane and lipoproteins and 63 secreted proteins. This accounts for about 43% of the 3616 proteins encoded in the B. pumilus Jo2 genome sequence. By using GC–MS, IP-LC/MS and H NMR methods numerous metabolites were analyzed and assigned to reconstructed metabolic pathways. In the genome sequence a functional secretion system including the components of the Sec- and Tat-secretion machinery was found. Analysis of the exoproteome revealed secretion of about 70 proteins with predicted secretion signals. In addition, selected production-relevant genome features such as restriction modification systems and NRPS clusters of B. pumilus Jo2 are discussed. Y1 - 2014 U6 - https://doi.org/10.1016/j.jbiotec.2014.08.028 SN - 1873-4863 (E-Journal); 0168-1656 (Print) IS - 192(A) SP - 204 EP - 214 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Wiegand, Sandra A1 - Dietrich, Sascha A1 - Hertel, Robert A1 - Bongaerts, Johannes A1 - Evers, Stefan A1 - Volland, Sonja A1 - Daniel, Rolf A1 - Liesegang, Heiko T1 - RNA-Seq of Bacillus licheniformis: active regulatory RNA features expressed within a productive fermentation JF - BMC genomics Y1 - 2013 SN - 1471-2164 VL - Vol. 14 SP - 667 PB - BioMed Central CY - London ER - TY - JOUR A1 - Deppe, Veronika Maria A1 - Klatte, Stephanie A1 - Bongaerts, Johannes A1 - Maurer, Karl-Heinz A1 - O'Connell, Timothy A1 - Meinhardt, Friedhelm T1 - Genetic control of Amadori product degradation in Bacillus subtilis via regulation of frlBONMD expression by FrlR JF - Applied and environmental microbiology Y1 - 2011 SN - 1098-5336 (E-Journal); 0003-6919 (Print); 0099-2240 (Print) VL - Vol. 77 IS - No. 9 SP - 2839 EP - 2846 PB - American Society of Mechanical Engineers (ASME) CY - New York ER - TY - JOUR A1 - Bronder, Thomas A1 - Poghossian, Arshak A1 - Scheja, S. A1 - Wu, Chunsheng A1 - Keusgen, M. A1 - Schöning, Michael Josef T1 - Electrostatic Detection of Unlabelled Single- and Double-stranded DNA Using Capacitive Field-effect Devices Functionalized with a Positively Charged Polyelectrolyte Layer JF - Procedia Engineering N2 - Capacitive field-effect electrolyte-insulator-semiconductor sensors consisting of an Al-p-Si-SiO2 structure have been used for the electrical detection of unlabelled single- and double-stranded DNA (dsDNA) molecules by their intrinsic charge. A simple functionalization protocol based on the layer-by-layer (LbL) technique was used to prepare a weak polyelectrolyte/probe-DNA bilayer, followed by the hybridization with complementary target DNA molecules. Due to the flat orientation of the LbL-adsorbed DNA molecules, a high sensor signal has been achieved. In addition, direct label-free detection of in-solution hybridized dsDNA molecules has been studied. Y1 - 2015 U6 - https://doi.org/10.1016/j.proeng.2015.08.710 SN - 1877-7058 N1 - Eurosensors 2015 VL - 120 SP - 544 EP - 547 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Poghossian, Arshak A1 - Ingebrandt, S. A1 - Abouzar, Maryam H. A1 - Schöning, Michael Josef T1 - Label-free detection of charged macromolecules by using a field-effect-based sensor platform: Experiments and possible mechanisms of signal generation JF - Applied Physics A: Materials Science & Processing. 87 (2007), H. 3 Y1 - 2007 SN - 0947-8396 N1 - Special Issue “From Surface Science to Nanoscale Devices” SP - 517 EP - 524 ER - TY - JOUR A1 - Poghossian, Arshak A1 - Karschuck, Tobias A1 - Wagner, Patrick A1 - Schöning, Michael Josef T1 - Field-Effect Capacitors Decorated with Ligand-Stabilized Gold Nanoparticles: Modeling and Experiments JF - Biosensors N2 - Nanoparticles are recognized as highly attractive tunable materials for designing field-effect biosensors with enhanced performance. In this work, we present a theoretical model for electrolyte-insulator-semiconductor capacitors (EISCAP) decorated with ligand-stabilized charged gold nanoparticles. The charged AuNPs are taken into account as additional, nanometer-sized local gates. The capacitance-voltage (C–V) curves and constant-capacitance (ConCap) signals of the AuNP-decorated EISCAPs have been simulated. The impact of the AuNP coverage on the shift of the C–V curves and the ConCap signals was also studied experimentally on Al–p-Si–SiO₂ EISCAPs decorated with positively charged aminooctanethiol-capped AuNPs. In addition, the surface of the EISCAPs, modified with AuNPs, was characterized by scanning electron microscopy for different immobilization times of the nanoparticles. KW - aminooctanethiol KW - nanoparticle coverage KW - capacitive model KW - gold nanoparticles KW - field-effect sensor KW - electrolyte-insulator-semiconductor capacitors Y1 - 2022 U6 - https://doi.org/10.3390/bios12050334 SN - 2079-6374 N1 - This article belongs to the Special Issue "Biosensors in Nanotechnology" VL - 12 IS - 5 PB - MDPI CY - Basel ER - TY - JOUR A1 - Borgmeier, Claudia A1 - Bongaerts, Johannes A1 - Meinhardt, Friedhelm T1 - Genetic analysis of the Bacillus licheniformis degSU operon and the impact of regulatory mutations on protease production JF - Journal of biotechnology N2 - Disruption experiments targeted at the Bacillus licheniformis degSU operon and GFP-reporter analysis provided evidence for promoter activity immediately upstream of degU. pMutin mediated concomitant introduction of the degU32 allele – known to cause hypersecretion in Bacillus subtilis – resulted in a marked increase in protease activity. Application of 5-fluorouracil based counterselection through establishment of a phosphoribosyltransferase deficient Δupp strain eventually facilitated the marker-free introduction of degU32 leading to further protease enhancement achieving levels as for hypersecreting wild strains in which degU was overexpressed. Surprisingly, deletion of rapG – known to interfere with DegU DNA-binding in B. subtilis – did not enhance protease production neither in the wild type nor in the degU32 strain. The combination of degU32 and Δupp counterselection in the type strain is not only equally effective as in hypersecreting wild strains with respect to protease production but furthermore facilitates genetic strain improvement aiming at biological containment and effectiveness of biotechnological processes. KW - Marker-free mutagenesis KW - Extracellular enzymes KW - Uracil-phosphoribosyltransferase KW - Hypersecretion Y1 - 2012 U6 - https://doi.org/10.1016/j.jbiotec.2012.02.011 SN - 1873-4863 (E-Journal); 0168-1656 (Print) VL - 159 IS - 1-2 SP - 12 EP - 20 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Molinnus, Denise A1 - Sorich, Maren A1 - Bartz, Alexander A1 - Siegert, Petra A1 - Willenberg, Holger S. A1 - Lisdat, Fred A1 - Poghossian, Arshak A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Towards an adrenaline biosensor based on substrate recycling amplification in combination with an enzyme logic gate JF - Sensors and Actuators B: Chemical N2 - An amperometric biosensor using a substrate recycling principle was realized for the detection of low adrenaline concentrations (1 nM) by measurements in phosphate buffer and Ringer’s solution at pH 6.5 and pH 7.4, respectively. In proof-of-concept experiments, a Boolean logic-gate principle has been applied to develop a digital adrenaline biosensor based on an enzyme AND logic gate. The obtained results demonstrate that the developed digital biosensor is capable for a rapid qualitative determination of the presence/absence of adrenaline in a YES/NO statement. Such digital biosensor could be used in clinical diagnostics for the control of a correct insertion of a catheter in the adrenal veins during adrenal venous-sampling procedure. Y1 - 2016 U6 - https://doi.org/10.1016/j.snb.2016.06.064 SN - 0925-4005 VL - 237 SP - 190 EP - 195 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Poghossian, Arshak A1 - Katz, Evgeny A1 - Schöning, Michael Josef T1 - Enzyme logic AND-Reset and OR-Reset gates based on a field-effect electronic transducer modified with multi-enzyme membrane JF - Chemical Communications N2 - Capacitive field-effect sensors modified with a multi-enzyme membrane have been applied for an electronic transduction of biochemical signals processed by enzyme-based AND-Reset and OR-Reset logic gates. The local pH change at the sensor surface induced by the enzymatic reaction was used for the activation of the Reset function for the first time. Y1 - 2015 U6 - https://doi.org/10.1039/C5CC01362C VL - 51 SP - 6564 EP - 6567 PB - Royal Society of Chemistry (RSC) CY - Cambridge ER - TY - JOUR A1 - Abouzar, Maryam H. A1 - Poghossian, Arshak A1 - Razavi, A. A1 - Williams, O. A. A1 - Bijnens, N. A1 - Wagner, P. A1 - Schöning, Michael Josef T1 - Characterisation of capacitive field-effect sensors with a nanocrystalline-diamond film as transducer material for multi-parameter sensing JF - Biosensors and Bioelectronics. 24 (2009), H. 5 Y1 - 2009 SN - 0956-5663 N1 - Selected Papers from the Tenth World Congress on Biosensors Shangai, China, May 14-16, 2008 ; Zeitschrift früher u.d.T. : Biosensors SP - 1298 EP - 1304 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Turek, M. A1 - Keusgen, M. A1 - Poghossian, Arshak A1 - Mulchandani, A. A1 - Wang, J. A1 - Schöning, Michael Josef T1 - Enzyme-modified electrolyte-insulator-semiconductor sensors JF - Journal of Contemporary Physics. 43 (2008), H. 2 Y1 - 2008 SN - 1934-9378 N1 - Armenian Academy of Sciences SP - 82 EP - 85 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 - Bäcker, Matthias A1 - Beging, Stefan A1 - Biselli, Manfred A1 - Poghossian, Arshak A1 - Wang, J. A1 - Zang, Werner A1 - Wagner, Patrick A1 - Schöning, Michael Josef T1 - Concept for a solid-state multi-parameter sensor system for cell-culture monitoring JF - Electrochimica Acta. 54 (2009), H. 25 Sp. Iss. SI Y1 - 2009 SN - 0013-4686 SP - 6107 EP - 6112 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Buniatyan, Vahe V. A1 - Matirosyan, N. A1 - Abouzar, Maryam H. A1 - Schubert, J. A1 - Zander, W. A1 - Gevorgian, S. A1 - Schöning, Michael Josef A1 - Poghossian, Arshak T1 - Capacitive field-effect pH sensor based on an electrolyte-ferroelectric-insulator-semiconductor structure JF - SENSOR 2009 : : 14th International Conference on Sensors, Technologies, Electronics and Applications; Nürnberg, Germany, 26 - 28 May 2009; proceedings; [part of] Sensor + Test Conference 2009 / AMA, Fachverband für Sensorik e.V Y1 - 2009 SN - 9783981099355 N1 - AMA, Fachverband für Sensorik ; Sensor International Conference ; (14 : ; 2009.05.26-28 : ; Nürnberg) SP - 317 EP - 322 PB - AMA Service CY - Wunstorf ER - TY - JOUR A1 - Poghossian, Arshak A1 - Berndsen, Lars A1 - Schöning, Michael Josef T1 - Chemical sensor as physical sensor: ISFET-based flowvelocity, flow-direction and diffusion-coefficient sensor JF - Sensors and Actuators B. 95 (2003), H. 1-3 Y1 - 2003 SN - 0925-4005 SP - 384 EP - 390 ER - TY - JOUR A1 - Poghossian, Arshak A1 - Wagner, Holger A1 - Schöning, Michael Josef T1 - Functional testing and characterisation of (bio-)chemical sensors on wafer level JF - Sensors and Actuators B: Chemical. 154 (2011), H. 2 Y1 - 2011 SN - 1873-3077 N1 - EUROSENSORS XXIII SP - 169 EP - 173 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Poghossian, Arshak A1 - Berndsen, L. A1 - Schultze, J. W. A1 - Lüth, H. A1 - Schöning, Michael Josef T1 - „High order“ hybrid sensor module based on an identical transducer principle 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 - 143 EP - 152 PB - Electrochemical Society CY - Pennington, NJ 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 - Bäcker, Matthias A1 - Poghossian, Arshak A1 - Abouzar, Maryam H. A1 - Wenmackers, Sylvia A1 - Janssens, Stoffel D. A1 - Haenen, Ken A1 - Wagner, Patrick A1 - Schöning, Michael Josef T1 - Capacitive field-effect (bio-)chemical sensors based on nanocrystalline diamond films JF - Diamond Electronics and Bioelectronics — Fundamentals to Applications III, edited by P. Bergonzo, [u.a.] Y1 - 2010 N1 - MRS Proceedings Volume 1203 paper 1203-J17-31 ; Mater. Res. Soc. Sympos. Proc. Vol 1203 (2010) ; Materials Research Society SP - 1 EP - 6 ER - TY - JOUR A1 - Wendlandt, Tim A1 - Koch, Claudia A1 - Britz, Beate A1 - Liedek, Anke A1 - Schmidt, Nora A1 - Werner, Stefan A1 - Gleba, Yuri A1 - Vahidpour, Farnoosh A1 - Welden, Melanie A1 - Poghossian, Arshak A1 - Schöning, Michael Josef T1 - Facile Purification and Use of Tobamoviral Nanocarriers for Antibody-Mediated Display of a Two-Enzyme System JF - Viruses N2 - Immunosorbent turnip vein clearing virus (TVCV) particles displaying the IgG-binding domains D and E of Staphylococcus aureus protein A (PA) on every coat protein (CP) subunit (TVCVPA) were purified from plants via optimized and new protocols. The latter used polyethylene glycol (PEG) raw precipitates, from which virions were selectively re-solubilized in reverse PEG concentration gradients. This procedure improved the integrity of both TVCVPA and the wild-type subgroup 3 tobamovirus. TVCVPA could be loaded with more than 500 IgGs per virion, which mediated the immunocapture of fluorescent dyes, GFP, and active enzymes. Bi-enzyme ensembles of cooperating glucose oxidase and horseradish peroxidase were tethered together on the TVCVPA carriers via a single antibody type, with one enzyme conjugated chemically to its Fc region, and the other one bound as a target, yielding synthetic multi-enzyme complexes. In microtiter plates, the TVCVPA-displayed sugar-sensing system possessed a considerably increased reusability upon repeated testing, compared to the IgG-bound enzyme pair in the absence of the virus. A high coverage of the viral adapters was also achieved on Ta2O5 sensor chip surfaces coated with a polyelectrolyte interlayer, as a prerequisite for durable TVCVPA-assisted electrochemical biosensing via modularly IgG-assembled sensor enzymes. KW - biosensor KW - horseradish peroxidase (HRP) KW - glucose oxidase (GOx) KW - enzyme cascade KW - turnip vein clearing virus (TVCV) KW - tobacco mosaic virus (TMV) Y1 - 2023 U6 - https://doi.org/doi.org/10.3390/v15091951 SN - 1999-4915 N1 - This article belongs to the Special Issue "Tobamoviruses 2023" VL - 9 IS - 15 PB - MDPI CY - Basel 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 - JOUR A1 - Poghossian, Arshak A1 - Schöning, Michael Josef T1 - Recent progress in silicon-based biologically sensitive field-effect devices JF - Current Opinion in Electrochemistry N2 - Biologically sensitive field-effect devices (BioFEDs) advantageously combine the electronic field-effect functionality with the (bio)chemical receptor’s recognition ability for (bio)chemical sensing. In this review, basic and widely applied device concepts of silicon-based BioFEDs (ion-sensitive field-effect transistor, silicon nanowire transistor, electrolyte-insulator-semiconductor capacitor, light-addressable potentiometric sensor) are presented and recent progress (from 2019 to early 2021) is discussed. One of the main advantages of BioFEDs is the label-free sensing principle enabling to detect a large variety of biomolecules and bioparticles by their intrinsic charge. The review encompasses applications of BioFEDs for the label-free electrical detection of clinically relevant protein biomarkers, deoxyribonucleic acid molecules and viruses, enzyme-substrate reactions as well as recording of the cell acidification rate (as an indicator of cellular metabolism) and the extracellular potential. Y1 - 2021 U6 - https://doi.org/10.1016/j.coelec.2021.100811 SN - 2451-9103 IS - Article number: 100811 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Poghossian, Arshak A1 - Schöning, Michael Josef A1 - Schroth, P. A1 - Simonis, A. A1 - Lüth, H. T1 - An ISFET-based penicillin sensor with high sensitivity, low detection limit and long lifetime JF - Sensors and Actuators B. 76 (2001), H. 1-3 Y1 - 2001 SN - 0925-4005 SP - 519 EP - 526 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 - https://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 - Siqueira, Jose R. A1 - Werner, Frederik A1 - Bäcker, Matthias A1 - Poghossian, Arshak A1 - Zucolotto, Valtencir A1 - Oliveira, Osvaldo N. Jr. A1 - Schöning, Michael Josef T1 - Layer-by-Layer Assembly of Carbon Nanotubes Incorporated in Light-Addressable Potentiometric Sensors JF - Journal of Physical Chemistry C. 113 (2009), H. 33 Y1 - 2009 SN - 1932-7455 SP - 14765 EP - 14770 PB - American Chemical Society CY - Washington, DC ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Brinkmann, D. A1 - Rolka, David A1 - Demuth, C. A1 - Poghossian, Arshak T1 - CIP (cleaning-in-place) suitable “non-glass” pH sensor based on a Ta2O5-gate EIS structure JF - Sensors and Actuators B: Chemical. 111-112 (2005) Y1 - 2005 SN - 0925-4005 N1 - Eurosensors XVIII 2004 - The 18th European Conference on Solid-State Transducers SP - 423 EP - 429 ER - TY - JOUR A1 - Poghossian, Arshak A1 - Werner, Frederik A1 - Buniatyan, V. V. A1 - Wagner, Torsten A1 - Miamoto, K. A1 - Yoshinobu, T. A1 - Schöning, Michael Josef T1 - Towards addressability of light-addressable potentiometric sensors: Shunting effect of non-illuminated region and cross-talk JF - Sensor and Actuators B: Chemical N2 - The LAPS (light-addressable potentiometric sensor) platform is one of the most attractive approaches for chemical and biological sensing with many applications ranging from pH and ion/analyte concentration measurements up to cell metabolism detection and chemical imaging. However, although it is generally accepted that LAPS measurements are spatially resolved, the light-addressability feature of LAPS devices has not been discussed in detail so far. In this work, an extended electrical equivalent-circuit model of the LAPS has been presented, which takes into account possible cross-talk effects due to the capacitive coupling of the non-illuminated region. A shunting effect of the non-illuminated area on the measured photocurrent and addressability of LAPS devices has been studied. It has been shown, that the measured photocurrent will be determined not only by the local interfacial potential in the illuminated region but also by possible interfacial potential changes in the non-illuminated region, yielding cross-talk effects. These findings were supported by the experimental investigations of a penicillin-sensitive multi-spot LAPS and a metal-insulator-semiconductor LAPS as model systems. Y1 - 2017 U6 - https://doi.org/10.1016/j.snb.2017.01.047 SN - 0925-4005 IS - 244 SP - 1071 EP - 1079 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Poghossian, Arshak T1 - Detection of charged macromolecules by means of field-effect devices (FEDs): possibilities and limitations JF - Electrochemical sensors, biosensors and their biomedical applications / ed. by Xueji Zhang ... Y1 - 2008 SN - 978-0-12-373738-0 SP - 187 EP - 212 PB - Elsevier Acad. Press CY - Amsterdam ER - TY - JOUR A1 - Molinnus, Denise A1 - Bäcker, Matthias A1 - Iken, Heiko A1 - Poghossian, Arshak A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Concept for a biomolecular logic chip with an integrated sensor and actuator function JF - Physica status solidi (a) N2 - A concept for a new generation of an integrated multi-functional biosensor/actuator system is developed, which is based on biomolecular logic principles. Such a system is expected to be able to detect multiple biochemical input signals simultaneously and in real-time and convert them into electrical output signals with logical operations such as OR, AND, etc. The system can be designed as a closed-loop drug release device triggered by an enzyme logic gate, while the release of the drug induced by the actuator at the required dosage and timing will be controlled by an additional drug sensor. Thus, the system could help to make an accurate and specific diagnosis. The presented concept is exemplarily demonstrated by using an enzyme logic gate based on a glucose/glucose oxidase system, a temperature-responsive hydrogel mimicking the actuator function and an insulin (drug) sensor. In this work, the results of functional testing of individual amperometric glucose and insulin sensors as well as an impedimetric sensor for the detection of the hydrogel swelling/shrinking are presented. Y1 - 2015 U6 - https://doi.org/10.1002/pssa.201431913 SN - 1862-6319 VL - 212 IS - 6 SP - 1382 EP - 1388 PB - Wiley CY - Weinheim 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 - Wu, Chunsheng A1 - Poghossian, Arshak A1 - Bronder, Thomas A1 - Schöning, Michael Josef T1 - Sensing of double-stranded DNA molecules by their intrinsic molecular charge using the light-addressable potentiometric sensor JF - Sensors and Actuators B: Chemical N2 - A multi-spot light-addressable potentiometric sensor (LAPS), which belongs to the family of semiconductor field-effect devices, was applied for label-free detection of double-stranded deoxyribonucleic acid (dsDNA) molecules by their intrinsic molecular charge. To reduce the distance between the DNA charge and sensor surface and thus, to enhance the electrostatic coupling between the dsDNA molecules and the LAPS, the negatively charged dsDNA molecules were electrostatically adsorbed onto the gate surface of the LAPS covered with a positively charged weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)). The surface potential changes in each spot of the LAPS, induced by the layer-by-layer adsorption of a PAH/dsDNA bilayer, were recorded by means of photocurrent-voltage and constant-photocurrent measurements. In addition, the surface morphology of the gate surface before and after consecutive electrostatic adsorption of PAH and dsDNA layers was studied by atomic force microscopy measurements. Moreover, fluorescence microscopy was used to verify the successful adsorption of dsDNA molecules onto the PAH-modified LAPS surface. A high sensor signal of 25 mV was registered after adsorption of 10 nM dsDNA molecules. The lower detection limit is down to 0.1 nM dsDNA. The obtained results demonstrate that the PAH-modified LAPS device provides a convenient and rapid platform for the direct label-free electrical detection of in-solution hybridized dsDNA molecules. KW - Layer-by-layer adsorption KW - Poly(allylamine hydrochloride) KW - Label-free detection KW - DNA biosensor KW - LAPS KW - Field effect Y1 - 2016 U6 - https://doi.org/10.1016/j.snb.2016.02.004 SN - 0925-4005 IS - 229 SP - 506 EP - 512 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Poghossian, Arshak A1 - Schöning, Michael Josef T1 - Label-free sensing of biomolecules with field-effect devices for clinical applications JF - Electroanalysis N2 - Among the variety of transducer concepts proposed for label-free detection of biomolecules, the semiconductor field-effect device (FED) is one of the most attractive platforms. As medical techniques continue to progress towards diagnostic and therapies based on biomarkers, the ability of FEDs for a label-free, fast and real-time detection of multiple pathogenic and physiologically relevant molecules with high specificity and sensitivity offers very promising prospects for their application in point-of-care and personalized medicine for an early diagnosis and treatment of diseases. The presented paper reviews recent advances and current trends in research and development of different FEDs for label-free, direct electrical detection of charged biomolecules by their intrinsic molecular charge. The authors are mainly focusing on the detection of the DNA hybridization event, antibody-antigen affinity reaction as well as clinically relevant biomolecules such as cardiac and cancer biomarkers. Y1 - 2014 U6 - https://doi.org/10.1002/elan.201400073 SN - 1521-4109 (E-Journal); 1040-0397 (Print) VL - 26 IS - 6 SP - 1197 EP - 1213 PB - Wiley-VCH CY - Weinheim 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 - https://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 - 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 - https://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 - Huck, Christina A1 - Poghossian, Arshak A1 - Bäcker, Matthias A1 - Chaudhuri, S. A1 - Zander, W. A1 - Schubert, J. A1 - Begoyan, V. K. A1 - Buniatyan, V. V. A1 - Wagner, P. A1 - Schöning, Michael Josef T1 - Capacitively coupled electrolyte-conductivity sensor based on high-k material of barium strontium titanate JF - Sensors and actuators. B: Chemical Y1 - 2014 U6 - https://doi.org/10.1016/j.snb.2014.02.103 SN - 1873-3077 (E-Journal); 0925-4005 (Print) IS - 198 SP - 102 EP - 109 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Poghossian, Arshak A1 - Abouzar, Maryam H. A1 - Amberger, F. A1 - Mayer, D. A1 - Han, Y. A1 - Ingebrandt, S. A1 - Offenhäusser, A. A1 - Schöning, Michael Josef T1 - Field-effect sensors with charged macromolecules: Characterisation by capacitance–voltage, constant-capacitance, impedance spectroscopy and atomic-force microscopy methods JF - Biosensors and Bioelectronics. 22 (2007), H. 9-10 Y1 - 2007 SN - 0956-5663 N1 - Selected Papers from the Ninth World Congress On Biosensors. Toronto, Canada 10 - 12 May 2006, Alice X. J . Tang SP - 2100 EP - 2107 ER - TY - JOUR A1 - Schusser, Sebastian A1 - Menzel, S. A1 - Bäcker, Matthias A1 - Leinhos, Marcel A1 - Poghossian, Arshak A1 - Wagner, P. A1 - Schöning, Michael Josef T1 - Degradation of thin poly(lactic acid) films: characterization by capacitance-voltage, atomic force microscopy, scanning electron microscopy and contact-angle measurements JF - Electrochimica Acta Y1 - 2013 SN - 1873-3859 (E-Journal); 0013-4686 (Print) VL - Vol. 113 SP - 779 EP - 784 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Bäcker, Matthias A1 - Koch, Claudia A1 - Eiben, Sabine A1 - Geiger, Fania A1 - Eber, Fabian A1 - Gliemann, Hartmut A1 - Poghossian, Arshak A1 - Wege, Christina A1 - Schöning, Michael Josef T1 - Tobacco mosaic virus as enzyme nanocarrier for electrochemical biosensors JF - Sensors and Actuators B: Chemical N2 - The conjunction of (bio-)chemical recognition elements with nanoscale biological building blocks such as virus particles is considered as a very promising strategy for the creation of biohybrids opening novel opportunities for label-free biosensing. This work presents a new approach for the development of biosensors using tobacco mosaic virus (TMV) nanotubes or coat proteins (CPs) as enzyme nanocarriers. Sensor chips combining an array of Pt electrodes loaded with glucose oxidase (GOD)-modified TMV nanotubes or CP aggregates were used for amperometric detection of glucose as a model system for the first time. The presence of TMV nanotubes or CPs on the sensor surface allows binding of a high amount of precisely positioned enzymes without substantial loss of their activity, and may also ensure accessibility of their active centers for analyte molecules. Specific and efficient immobilization of streptavidin-conjugated GOD ([SA]-GOD) complexes on biotinylated TMV nanotubes or CPs was achieved via bioaffinity binding. These layouts were tested in parallel with glucose sensors with adsorptively immobilized [SA]-GOD, as well as [SA]-GOD crosslinked with glutardialdehyde, and came out to exhibit superior sensor performance. The achieved results underline a great potential of an integration of virus/biomolecule hybrids with electronic transducers for future applications in biosensorics and biochips. Y1 - 2017 U6 - https://doi.org/10.1016/j.snb.2016.07.096 SN - 0925-4005 VL - 238 SP - 716 EP - 722 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Bäcker, Matthias A1 - Kramer, F. A1 - Huck, Christina A1 - Poghossian, Arshak A1 - Bratov, A. A1 - Abramova, N. A1 - Schöning, Michael Josef T1 - Planar and 3D interdigitated electrodes for biosensing applications: The impact of a dielectric barrier on the sensor properties JF - Physica Status Solidi (A) - Applications and Materials Science N2 - Planar and three-dimensional (3D) interdigitated electrodes (IDE) with electrode digits separated by an insulating barrier of different heights were electrochemically characterized and compared in terms of their sensing properties. Due to the impact of the surface resistance, both types of IDE structures display a non-linear behavior in low-ionic strength solutions. The experimental data were fitted to an electrical equivalent circuit and interpreted taking into account the surface-charge-governed properties. The effect of a charged polyelectrolyte layer electrostatically assembled onto the sensor surface on the surface resistance in solutions with different KCl concentration is studied. In case of the same electrode footprint, 3D-IDEs show a larger cell constant and a higher sensitivity to molecular adsorption than that of planar IDEs. The obtained results demonstrate the potential of 3D-IDEs as a new transducer structure for a direct label-free sensing of charged molecules. Y1 - 2014 U6 - https://doi.org/10.1002/pssa.201330416 SN - 1521-396X (E-Journal); 1862-6319 (E-Journal); 0031-8965 (Print); 1862-6300 (Print) VL - 211 IS - 6 SP - 1357 EP - 1363 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Poghossian, Arshak A1 - Weil, M. H. A1 - Bäcker, Matthias A1 - Mayer, D. A1 - Schöning, Michael Josef T1 - Field-effect Devices Functionalised with Gold-Nanoparticle/Macromolecule Hybrids: New Opportunities for a Label-Free Biosensing JF - Procedia Engineering N2 - Field-effect capacitive electrolyte-insulator-semiconductor (EIS) sensors functionalised with citrate-capped gold nanoparticles (AuNP) have been used for the electrostatic detection of macromolecules by their intrinsic molecular charge. The EIS sensor detects the charge changes in the AuNP/macromolecule hybrids induced by the adsorption or binding events. A feasibility of the proposed detection scheme has been exemplary demonstrated by realising EIS sensors for the detection of poly-D-lysine molecules. Y1 - 2012 U6 - https://doi.org/10.1016/j.proeng.2012.09.136 SN - 1877-7058 N1 - Part of special issue "26th European Conference on Solid-State Transducers, EUROSENSOR 2012" IS - 47 SP - 273 EP - 276 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Moseley, Fiona A1 - Halamek, Jan A1 - Kramer, Friederike A1 - Poghossian, Arshak A1 - Schöning, Michael Josef A1 - Katz, Evgeny T1 - An enzyme-based reversible CNOT logic gate realized in a flow system JF - Analyst N2 - An enzyme system organized in a flow device was used to mimic a reversible Controlled NOT (CNOT) gate with two input and two output signals. Reversible conversion of NAD⁺ and NADH cofactors was used to perform a XOR logic operation, while biocatalytic hydrolysis of p-nitrophenyl phosphate resulted in an Identity operation working in parallel. The first biomolecular realization of a CNOT gate is promising for integration into complex biomolecular networks and future biosensor/biomedical applications. Y1 - 2014 U6 - https://doi.org/10.1039/C4AN00133H SN - 1364-5528 (E-Journal) ; 0003-2654 (Print) VL - 139 IS - 8 SP - 1839 EP - 1842 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Abouzar, Maryam H. A1 - Werner, Moritz A1 - Schöning, Michael Josef A1 - Poghossian, Arshak T1 - Capacitance–voltage and impedance-spectroscopy characteristics of nanoplate EISOI capacitors JF - Physica status solidi (a) : applications and material science. 208 (2011), H. 6 Y1 - 2011 SN - 1862-6319 SP - 1327 EP - 1332 PB - Wiley-VCH CY - Berlin ER - TY - JOUR A1 - Pourshahidi, Ali Mohammad A1 - Engelmann, Ulrich M. A1 - Offenhäusser, Andreas A1 - Krause, Hans-Joachim T1 - Resolving ambiguities in core size determination of magnetic nanoparticles from magnetic frequency mixing data JF - Journal of Magnetism and Magnetic Materials N2 - Frequency mixing magnetic detection (FMMD) has been widely utilized as a measurement technique in magnetic immunoassays. It can also be used for the characterization and distinction (also known as “colourization”) of different types of magnetic nanoparticles (MNPs) based on their core sizes. In a previous work, it was shown that the large particles contribute most of the FMMD signal. This leads to ambiguities in core size determination from fitting since the contribution of the small-sized particles is almost undetectable among the strong responses from the large ones. In this work, we report on how this ambiguity can be overcome by modelling the signal intensity using the Langevin model in thermodynamic equilibrium including a lognormal core size distribution fL(dc,d0,σ) fitted to experimentally measured FMMD data of immobilized MNPs. For each given median diameter d0, an ambiguous amount of best-fitting pairs of parameters distribution width σ and number of particles Np with R2 > 0.99 are extracted. By determining the samples’ total iron mass, mFe, with inductively coupled plasma optical emission spectrometry (ICP-OES), we are then able to identify the one specific best-fitting pair (σ, Np) one uniquely. With this additional externally measured parameter, we resolved the ambiguity in core size distribution and determined the parameters (d0, σ, Np) directly from FMMD measurements, allowing precise MNPs sample characterization. Y1 - 2022 U6 - https://doi.org/10.1016/j.jmmm.2022.169969 SN - 0304-8853 VL - 563 IS - In progress, Art. No. 169969 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Poghossian, Arshak T1 - Silicon-based field-effect devices for (bio-)chemical sensing JF - International Conference on Advanced Semiconductor Devices and Microsystems, 2008. ASDAM 2008 Y1 - 2008 SN - 978-1-4244-2325-5 SP - 31 EP - 38 CY - Smolenice, Slovakia ER - TY - JOUR A1 - Poghossian, Arshak A1 - Bäcker, Matthias A1 - Mayer, Dirk A1 - Schöning, Michael Josef T1 - Gating capacitive field-effect sensors by the charge of nanoparticle/molecule hybrids JF - Nanoscale Y1 - 2015 U6 - https://doi.org/10.1039/C4NR05987E SN - 2040-3372 (E-Journal); 2040-3364 (Print) SP - 1023 EP - 1031 PB - Royal Society of Chemistry (RSC) CY - Cambridge ER - TY - JOUR A1 - Poghossian, Arshak A1 - Baade, A. A1 - Emons, H. A1 - Schöning, Michael Josef T1 - Application of ISFET for pH measurements in rain droplets JF - Sensors and Actuators B. 76 (2001), H. 1-3 Y1 - 2001 SN - 0925-4005 SP - 634 EP - 638 ER - TY - JOUR A1 - Kassab, T. A1 - Han, Y. A1 - Poghossian, Arshak A1 - Ingebrandt, S. A1 - Offenhäusser, A. A1 - Schöning, Michael Josef T1 - Detection of layerby-layer adsorbed polyelectrolytes by means of field-effect based capacitive EIS structures JF - Biomedizinische Technik. 49 (2004), H. 2 Y1 - 2004 SN - 0932-4666 SP - 1034 EP - 1035 ER - TY - JOUR A1 - Buniatyan, V. V. A1 - Matirosyan, N. W. A1 - Abouzar, Maryam H. A1 - Schöning, Michael Josef A1 - Poghossian, Arshak A1 - Schubert, J. A1 - Khachatryan, V. R. A1 - Soukiassyan, G. R. T1 - (Ba,Sr)TiO3 based electrolyte-insulator-semiconductor pHsensors: comparitive study JF - Semiconductor micro- and nanoelectronics : Proceedings of the Seventh International Conference , Tsakhcadzor, Armenia July 3-5 2009 Y1 - 2009 SP - 71 EP - 74 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 - JOUR A1 - Pourshahidi, Ali Mohammad A1 - Achtsnicht, Stefan A1 - Offenhäusser, Andreas A1 - Krause, Hans-Joachim ED - Offenhäusser, Andreas T1 - Frequency Mixing Magnetic Detection Setup Employing Permanent Ring Magnets as a Static Offset Field Source JF - Sensors N2 - Frequency mixing magnetic detection (FMMD) has been explored for its applications in fields of magnetic biosensing, multiplex detection of magnetic nanoparticles (MNP) and the determination of core size distribution of MNP samples. Such applications rely on the application of a static offset magnetic field, which is generated traditionally with an electromagnet. Such a setup requires a current source, as well as passive or active cooling strategies, which directly sets a limitation based on the portability aspect that is desired for point of care (POC) monitoring applications. In this work, a measurement head is introduced that involves the utilization of two ring-shaped permanent magnets to generate a static offset magnetic field. A steel cylinder in the ring bores homogenizes the field. By variation of the distance between the ring magnets and of the thickness of the steel cylinder, the magnitude of the magnetic field at the sample position can be adjusted. Furthermore, the measurement setup is compared to the electromagnet offset module based on measured signals and temperature behavior. KW - magnetic sensors KW - biosensors KW - frequency mixing magnetic detection KW - magnetic nanoparticles Y1 - 2022 U6 - https://doi.org/10.3390/s22228776 SN - 1424-8220 VL - 22 IS - 22 PB - MDPI CY - Basel ER - TY - JOUR A1 - Bronder, Thomas A1 - Poghossian, Arshak A1 - Jessing, Max P. A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Surface regeneration and reusability of label-free DNA biosensors based on weak polyelectrolyte-modified capacitive field-effect structures JF - Biosensors and Bioelectronics Y1 - 2019 U6 - https://doi.org/10.1016/j.bios.2018.11.019 SN - 0956-5663 VL - 126 SP - 510 EP - 517 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Poghossian, Arshak A1 - Malzahn, K. A1 - Abouzar, Maryam H. A1 - Mehndiratta, P. A1 - Katz, E. A1 - Schöning, Michael Josef T1 - Integration of biomolecular logic gates with field-effect transducers JF - Electrochimica Acta. 56 (2011), H. 26 Y1 - 2011 SN - 0013-4686 SP - 9661 EP - 9665 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Siqueira, José R. Jr. A1 - Abouzar, Maryam H. A1 - Bäcker, Matthias A1 - Zucolotto, Valtencir A1 - Poghossian, Arshak A1 - Oliveira, Osvaldo N. Jr. A1 - Schöning, Michael Josef T1 - Carbon nanotubes in nanostructured films: Potential application as amperometric and potentiometric field-effect (bio-)chemical sensors JF - physica status solidi (a) . 206 (2009), H. 3 Y1 - 2009 SN - 1862-6319 N1 - Special Issue: Engineering of Functional Interfaces (EnFI 08) SP - 462 EP - 467 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Wagner, Torsten A1 - Maris, Rob J. A1 - Ackermann, Hans-Josef A1 - Otto, Ralph A1 - Beging, Stefan A1 - Poghossian, Arshak A1 - Schöning, Michael Josef T1 - Handheld measurement device for field-effect sensor structures: Practical evaluation and limitations JF - Sensors and Actuators B: Chemical . 127 (2007), H. 1 Y1 - 2007 SN - 0925-4005 SP - 217 EP - 223 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 - Schusser, Sebastian A1 - Poghossian, Arshak A1 - Bäcker, Matthias A1 - Krischer, M. A1 - Leinhos, Marcel A1 - Wagner, P. A1 - Schöning, Michael Josef T1 - An application of field-effect sensors for in-situ monitoring of degradation of biopolymers JF - Sensors and actuators B: Chemical N2 - The characterization of the degradation kinetics of biodegradable polymers is mandatory with regard to their proper application. In the present work, polymer-modified electrolyte–insulator–semiconductor (PMEIS) field-effect sensors have been applied for in-situ monitoring of the pH-dependent degradation kinetics of the commercially available biopolymer poly(d,l-lactic acid) (PDLLA) in buffer solutions from pH 3 to pH 13. PDLLA films of 500 nm thickness were deposited on the surface of an Al–p-Si–SiO2–Ta2O5 structure from a polymer solution by means of spin-coating method. The PMEIS sensor is, in principle, capable to detect any changes in bulk, surface and interface properties of the polymer induced by degradation processes. A faster degradation has been observed for PDLLA films exposed to alkaline solutions (pH 9, pH 11 and pH 13). Y1 - 2015 U6 - https://doi.org/10.1016/j.snb.2014.10.058 SN - 1873-3077 (E-Journal); 0925-4005 (Print) VL - 207, Part B SP - 954 EP - 959 PB - Elsevier CY - Amsterdam 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 - Schöning, Michael Josef A1 - Abouzar, Maryam H. A1 - Ingebrandt, Sven A1 - Platen, Johannes A1 - Offenhäusser, Andreas A1 - Poghossian, Arshak ED - Comini, Elisabetta T1 - Towards label-free detection of charged macromolecules using field-effect-based structures : Scaling down from capacitive EIS sensor over ISFET to nano-scale devices JF - Nanostructured materials and hybrid composites for gas sensors and biomedical applications : symposium held April 18-20, 2006, San Francisco , California, U.S.A. Y1 - 2006 SN - 9781558998711 IS - paper 0915-R05-04 SP - 89 EP - 94 ER - TY - JOUR A1 - Abouzar, Maryam H. A1 - Pedraza, A. M. A1 - Schöning, Michael Josef A1 - Poghossian, Arshak T1 - Label-free DNA hybridization and denaturation detection by means of field-effect nanoplate SOI capacitors functionalized with gold nanoparticles JF - Procedia Engineering. 5 (2010) Y1 - 2010 SN - 1877-7058 N1 - Proc. Eurosensors XXIV, September 5–8, 2010, Linz, Austria SP - 918 EP - 921 ER - TY - JOUR A1 - Schusser, Sebastian A1 - Poghossian, Arshak A1 - Bäcker, Matthias A1 - Leinhos, Marcel A1 - Wagner, Patrick A1 - Schöning, Michael Josef T1 - Characterization of biodegradable polymers with capacitive field-effect sensors JF - Sensors and actuators B: Chemical N2 - In vitro studies of the degradation kinetic of biopolymers are essential for the design and optimization of implantable biomedical devices. In the presented work, a field-effect capacitive sensor has been applied for the real-time and in situ monitoring of degradation processes of biopolymers for the first time. The polymer-covered field-effect sensor is, in principle, capable to detect any changes in bulk, surface and interface properties of the polymer induced by degradation processes. The feasibility of this approach has been experimentally proven by using the commercially available biomedical polymer poly(D,L-lactic acid) (PDLLA) as a model system. PDLLA films of different thicknesses were deposited on the Ta₂O₅-gate surface of the field-effect structure from a polymer solution by means of spin-coating method. The polymer-modified field-effect sensors have been characterized by means of capacitance–voltage and impedance-spectroscopy method. The degradation of the PDLLA was accelerated by changing the degradation medium from neutral (pH 7.2) to alkaline (pH 9) condition, resulting in drastic changes in the capacitance and impedance spectra of the polymer-modified field-effect sensor. KW - Impedance spectroscopy KW - C–V method KW - Real-time monitoring KW - Poly(d,l-lacticacid) KW - (Bio)degradation KW - Field-effect sensor Y1 - 2012 U6 - https://doi.org/10.1016/j.snb.2012.07.099 SN - 0925-4005 N1 - Part of special issue "Selected Papers from the 14th International Meeting on Chemical Sensors" VL - 187 SP - 2 EP - 7 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Schusser, Sebastian A1 - Krischer, M. A1 - Molin, D. G. M. A1 - Akker, N. M. S. van den A1 - Bäcker, Matthias A1 - Poghossian, Arshak A1 - Schöning, Michael Josef T1 - Sensor System for in-situ and Real-time Monitoring of Polymer (bio) degradation JF - Procedia Engineering N2 - A sensor system for investigating (bio)degradationprocesses of polymers is presented. The system utilizes semiconductor field-effect sensors and is capable of monitoring the degradation process in-situ and in real-time. The degradation of the polymer poly(d,l-lactic acid) is exemplarily monitored in solutions with different pH value, pH-buffer solution containing the model enzyme lipase from Rhizomucormiehei and cell-culture medium containing supernatants from stimulated and non-stimulated THP-1-derived macrophages mimicking activation of the immune system. Y1 - 2015 U6 - https://doi.org/10.1016/j.proeng.2015.08.815 SN - 1877-7058 N1 - Eurosensors 2015 VL - 120 SP - 948 EP - 951 PB - Elsevier CY - Amsterdam 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 - 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 - 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 - Gun, Jenny A1 - Schöning, Michael Josef A1 - Abouzar, Maryam H. A1 - Poghossian, Arshak A1 - Katz, Evgeny T1 - Field-Effect Nanoparticle-Based Glucose Sensor on a Chip: Amplification Effect of Coimmobilized Redox Species JF - Electroanalysis. 20 (2008), H. 16 Y1 - 2008 SN - 1521-4109 SP - 1748 EP - 1753 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 - Honarvarfard, Elham A1 - Gamella, Maria A1 - Channaveerappa, Devika A1 - Darie, Costel C. A1 - Poghossian, Arshak A1 - Schöning, Michael Josef A1 - Katz, Evgeny T1 - Electrochemically Stimulated Insulin Release from a Modified Graphene–functionalized Carbon Fiber Electrode JF - Electroanalysis N2 - A graphene-functionalized carbon fiber electrode was modified with adsorbed polyethylenimine to introduce amino functionalities and then with trigonelline and 4-carboxyphenylboronic acid covalently bound to the amino groups. The trigonelline species containing quarterized pyridine groups produced positive charge on the electrode surface regardless of the pH value, while the phenylboronic acid species were neutral below pH 8 and negatively charged above pH 9 (note that their pKa=8.4). The total charge on the monolayer-modified electrode was positive at the neutral pH and negative at pH > 9. Note that 4-carboxyphenylboronic acid was attached to the electrode surface in molar excess to trigonelline, thus allowing the negative charge to dominate on the electrode surface at basic pH. Negatively charged fluorescent dye-labeled insulin (insulin-FITC) was loaded on the modified electrode surface at pH 7.0 due to its electrostatic attraction to the positively charged interface. The local pH in close vicinity to the electrode surface was increased to ca. 9–10 due to consumption of H+ ions upon electrochemical reduction of oxygen proceeding at the potential of −1.0 V (vs. Ag/AgCl) applied on the modified electrode. The process resulted in recharging of the electrode surface to the negative value due to the formation of the negative charge on the phenylboronic acid groups, thus resulting in the electrostatic repulsion of insulin-FITC and stimulating its release from the electrode surface. The insulin release was characterized by fluorescence spectroscopy (using the FITC-labeled insulin), by electrochemical measurements on an iridium oxide, IrOx, electrode and by mass spectrometry. The graphene-functionalized carbon fiber electrode demonstrated significant advantages in the signal-stimulated insulin release comparing with the carbon fiber electrode without the graphene species. Y1 - 2017 U6 - https://doi.org/10.1002/elan.201700095 SN - 1521-4109 VL - 29 IS - 6 SP - 1543 EP - 1553 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Molinnus, Denise A1 - Hardt, G. A1 - Käver, L. A1 - Willenberg, H.S. A1 - Kröger, J.-C. A1 - Poghossian, Arshak A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Chip-based biosensor for the detection of low adrenaline concentrations to support adrenal venous sampling JF - Sensor and Actuators B: Chemical N2 - A chip-based amperometric biosensor referring on using the bioelectrocatalytical amplification principle for the detection of low adrenaline concentrations is presented. The adrenaline biosensor has been prepared by modification of a platinum thin-film electrode with an enzyme membrane containing the pyrroloquinoline quinone-dependent glucose dehydrogenase and glutaraldehyde. Measuring conditions such as temperature, pH value, and glucose concentration have been optimized to achieve a high sensitivity and a low detection limit of about 1 nM adrenaline measured in phosphate buffer at neutral pH value. The response of the biosensor to different catecholamines has also been proven. Long-term stability of the adrenaline biosensor has been studied over 10 days. In addition, the biosensor has been successfully applied for adrenaline detection in human blood plasma for future biomedical applications. Furthermore, preliminary experiments have been carried to detect the adrenaline-concentration difference measured in peripheral blood and adrenal venous blood, representing the adrenal vein sampling procedure of a physician. Y1 - 2018 U6 - https://doi.org/10.1016/j.snb.2018.05.136 SN - 0925-4005 VL - 272 SP - 21 EP - 27 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Poghossian, Arshak A1 - Schultze, J. W. A1 - Schöning, Michael Josef T1 - Application of a (bio-)chemical sensor (ISFET) for the detection of physical parameters in liquids JF - Electrochimica Acta. 48 (2003), H. 20-22 Y1 - 2003 SP - 3289 EP - 3297 ER - TY - JOUR A1 - Bäcker, Matthias A1 - Delle, L. A1 - Poghossian, Arshak A1 - Biselli, Manfred A1 - Zang, Werner A1 - Wagner, P. A1 - Schöning, Michael Josef T1 - Electrochemical sensor array for bioprocess monitoring JF - Electrochimica Acta (2011) Y1 - 2011 VL - 56 IS - 26 SP - 9673 EP - 9678 PB - Elsevier CY - Amsterdam 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 - Schöning, Michael Josef A1 - Bronder, Thomas A1 - Wu, Chunsheng A1 - Scheja, Sabrina A1 - Jessing, Max A1 - Metzger-Boddien, Christoph A1 - Keusgen, Michael A1 - Poghossian, Arshak T1 - Label-Free DNA Detection with Capacitive Field-Effect Devices—Challenges and Opportunities JF - Proceedings N2 - Field-effect EIS (electrolyte-insulator-semiconductor) sensors modified with a positively charged weak polyelectrolyte layer have been applied for the electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization by the intrinsic molecular charge. The EIS sensors are able to detect the existence of target DNA amplicons in PCR (polymerase chain reaction) samples and thus, can be used as tool for a quick verification of DNA amplification and the successful PCR process. Due to their miniaturized setup, compatibility with advanced micro- and nanotechnologies, and ability to detect biomolecules by their intrinsic molecular charge, those sensors can serve as possible platform for the development of label-free DNA chips. Possible application fields as well as challenges and limitations will be discussed. Y1 - 2017 U6 - https://doi.org/10.3390/proceedings1080719 SN - 2504-3900 N1 - This article belongs to the Proceedings of "Proceedings of the 5th International Symposium on Sensor Science (I3S 2017)" VL - 1 IS - 8 SP - Artikel 719 PB - MDPI CY - Basel ER - TY - JOUR A1 - Mourzina, Y. A1 - Mai, T. A1 - Poghossian, Arshak A1 - Ermolenko, Y. A1 - Yoshinobu, T. A1 - Vlasov, Y. A1 - Iwasaki, H. A1 - Schöning, Michael Josef T1 - K+-selective field-effect sensors as transducers for bioelectronic applications JF - Electrochimica Acta. 48 (2003), H. 20-22 Y1 - 2003 SN - 0013-4686 SP - 3333 EP - 3339 ER - TY - JOUR A1 - Poghossian, Arshak A1 - Platen, J. A1 - Schöning, Michael Josef T1 - Towards self-aligned nanostructures by means of layerexpansion technique JF - Electrochimica Acta. 51 (2005), H. 5 Y1 - 2005 SN - 0013-4686 SP - 838 EP - 843 ER - TY - JOUR A1 - Bronder, Thomas A1 - Poghossian, Arshak A1 - Scheja, Sabrina A1 - Wu, Chunsheng A1 - Keusgen, Michael A1 - Mewes, Dieter A1 - Schöning, Michael Josef T1 - DNA Immobilization and Hybridization Detection by the Intrinsic Molecular Charge Using Capacitive Field-Effect Sensors Modified with a Charged Weak Polyelectrolyte Layer JF - Applied Materials & Interfaces N2 - Miniaturized setup, compatibility with advanced micro- and nanotechnologies, and ability to detect biomolecules by their intrinsic molecular charge favor the semiconductor field-effect platform as one of the most attractive approaches for the development of label-free DNA chips. In this work, a capacitive field-effect EIS (electrolyte–insulator–semiconductor) sensor covered with a layer-by-layer prepared, positively charged weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)) was used for the label-free electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization. The negatively charged probe single-stranded DNA (ssDNA) molecules were electrostatically adsorbed onto the positively charged PAH layer, resulting in a preferentially flat orientation of the ssDNA molecules within the Debye length, thus yielding a reduced charge-screening effect and a higher sensor signal. Each sensor-surface modification step (PAH adsorption, probe ssDNA immobilization, hybridization with complementary target DNA (cDNA), reducing an unspecific adsorption by a blocking agent, incubation with noncomplementary DNA (ncDNA) solution) was monitored by means of capacitance–voltage and constant-capacitance measurements. In addition, the surface morphology of the PAH layer was studied by atomic force microscopy and contact-angle measurements. High hybridization signals of 34 and 43 mV were recorded in low-ionic strength solutions of 10 and 1 mM, respectively. In contrast, a small signal of 4 mV was recorded in the case of unspecific adsorption of fully mismatched ncDNA. The density of probe ssDNA and dsDNA molecules as well as the hybridization efficiency was estimated using the experimentally measured DNA immobilization and hybridization signals and a simplified double-layer capacitor model. The results of field-effect experiments were supported by fluorescence measurements, verifying the DNA-immobilization and hybridization event. Y1 - 2015 U6 - https://doi.org/10.1021/acsami.5b05146 VL - 36 IS - 7 SP - 20068 EP - 20075 PB - American Chemical Society CY - Washington, DC 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 - https://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 - Bronder, Thomas A1 - Poghossian, Arshak A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Label-free detection of double-stranded DNA molecules with polyelectrolyte-modified capacitive field-effect sensors T1 - Markierungsfreie Detektion doppelsträngiger DNA Moleküle mit Hilfe von Polyelektrolyt-modifizierten kapazitiven Feldeffekt-Sensoren JF - tm - Technisches Messen N2 - In this study, polyelectrolyte-modified field-effect-based electrolyte-insulator-semiconductor (EIS) devices have been used for the label-free electrical detection of double-stranded deoxyribonucleic acid (dsDNA)molecules. The sensor-chip functionalization with a positively charged polyelectrolyte layer provides the possibility of direct adsorptive binding of negatively charged target DNA oligonucleotides onto theSiO2-chip surface.EIS sensors can be utilized as a tool to detect surface-charge changes; the electrostatic adsorption of oligonucleotides onto the polyelectrolyte layer leads to a measureable surface-potential change. Signals of 39mV have been recorded after the incubation with the oligonucleotide solution. Besides the electrochemical experiments, the successful adsorption of dsDNA onto the polyelectrolyte layer has been verified via fluorescence microscopy. The presented results demonstrate that the signal recording of EISchips, which are modified with a polyelectrolyte layer, canbe used as a favorable approach for a fast, cheap and simple detection method for dsDNA. Y1 - 2017 U6 - https://doi.org/10.1515/teme-2017-0015 VL - 84 IS - 10 SP - 628 EP - 634 PB - De Gruyter CY - Oldenbourg ER - TY - JOUR A1 - Jablonski, Melanie A1 - Poghossian, Arshak A1 - Severin, Robin A1 - Keusgen, Michael A1 - Wege, Christian A1 - Schöning, Michael Josef T1 - Capacitive Field-Effect Biosensor Studying Adsorption of Tobacco Mosaic Virus Particles JF - Micromachines N2 - Plant virus-like particles, and in particular, tobacco mosaic virus (TMV) particles, are increasingly being used in nano- and biotechnology as well as for biochemical sensing purposes as nanoscaffolds for the high-density immobilization of receptor molecules. The sensitive parameters of TMV-assisted biosensors depend, among others, on the density of adsorbed TMV particles on the sensor surface, which is affected by both the adsorption conditions and surface properties of the sensor. In this work, Ta₂O₅-gate field-effect capacitive sensors have been applied for the label-free electrical detection of TMV adsorption. The impact of the TMV concentration on both the sensor signal and the density of TMV particles adsorbed onto the Ta₂O₅-gate surface has been studied systematically by means of field-effect and scanning electron microscopy methods. In addition, the surface density of TMV particles loaded under different incubation times has been investigated. Finally, the field-effect sensor also demonstrates the label-free detection of penicillinase immobilization as model bioreceptor on TMV particles. KW - capacitive field-effect sensor KW - plant virus detection KW - tobacco mosaic virus (TMV) KW - TMV adsorption KW - Ta₂O₅ gate Y1 - 2021 U6 - https://doi.org/10.3390/mi12010057 VL - 12 IS - 1 PB - MDPI CY - Basel 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 - Schöning, Michael Josef A1 - Poghossian, Arshak A1 - Yoshinobu, Tatsuo A1 - Lüth, Hans T1 - Semiconductor-based field-effect structures for chemical sensing Y1 - 2001 SP - 188 EP - 198 ER - TY - JOUR A1 - Welden, Melanie A1 - Poghossian, Arshak A1 - Vahidpour, Farnoosh A1 - Wendlandt, Tim A1 - Keusgen, Michael A1 - Wege, Christina A1 - Schöning, Michael Josef T1 - Towards multi-analyte detection with field-effect capacitors modified with tobacco mosaic virus bioparticles as enzyme nanocarriers JF - Biosensors N2 - Utilizing an appropriate enzyme immobilization strategy is crucial for designing enzyme-based biosensors. Plant virus-like particles represent ideal nanoscaffolds for an extremely dense and precise immobilization of enzymes, due to their regular shape, high surface-to-volume ratio and high density of surface binding sites. In the present work, tobacco mosaic virus (TMV) particles were applied for the co-immobilization of penicillinase and urease onto the gate surface of a field-effect electrolyte-insulator-semiconductor capacitor (EISCAP) with a p-Si-SiO₂-Ta₂O₅ layer structure for the sequential detection of penicillin and urea. The TMV-assisted bi-enzyme EISCAP biosensor exhibited a high urea and penicillin sensitivity of 54 and 85 mV/dec, respectively, in the concentration range of 0.1–3 mM. For comparison, the characteristics of single-enzyme EISCAP biosensors modified with TMV particles immobilized with either penicillinase or urease were also investigated. The surface morphology of the TMV-modified Ta₂O₅-gate was analyzed by scanning electron microscopy. Additionally, the bi-enzyme EISCAP was applied to mimic an XOR (Exclusive OR) enzyme logic gate. KW - urease KW - enzyme-logic gate KW - bi-enzyme biosensor KW - capacitive field-effect sensor KW - tobacco mosaic virus (TMV) KW - penicillinase Y1 - 2022 U6 - https://doi.org/10.3390/bios12010043 SN - 2079-6374 N1 - This article belongs to the Special Issue "Biosensors: 10th Anniversary Feature Papers" VL - 12 IS - 1 PB - MDPI CY - Basel 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 - 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 - Poghossian, Arshak A1 - Thust, M. A1 - Schöning, Michael Josef A1 - Müller-Veggian, Mattea A1 - Kordos, P. A1 - Lüth, H. T1 - Cross-sensitivity of a capacitive penicillin sensor combined with a diffusion barrier JF - Sensors and Actuators B. 68 (2000), H. 1-3 Y1 - 2000 SN - 0925-4005 SP - 260 EP - 265 ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Brinkmann, D. A1 - Demuth, C. A1 - Poghossian, Arshak T1 - CIP (cleaning-in-place)-suitable „non-glass“ pH sensor based on a Ta2O5-gate EIS structure JF - Digest of technical papers : September 12 - 15, 2004, Rome, Italy, Pontificia Universitas Sancto Thoma Aquinate in Urbe / [conference chairperson: C. Di Natale]. Y1 - 2004 SN - 88-7621-282-5 N1 - Eurosensors ; (18, 2004, Roma) SP - 857 EP - 860 CY - Roma 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 - Honarvarfard, Elham A1 - Gamella, Maria A1 - Poghossian, Arshak A1 - Schöning, Michael Josef A1 - Katz, Evgeny T1 - An enzyme-based reversible Controlled NOT (CNOT) logic gate operating on a semiconductor transducer JF - Applied Materials Today N2 - An enzyme-based biocatalytic system mimicking operation of a logically reversible Controlled NOT (CNOT) gate has been interfaced with semiconductor electronic transducers. Electrolyte–insulator–semiconductor (EIS) structures have been used to transduce chemical changes produced by the enzyme system to an electronically readable capacitive output signal using field-effect features of the EIS device. Two enzymes, urease and esterase, were immobilized on the insulating interface of EIS structure producing local pH changes performing XOR logic operation controlled by various combinations of the input signals represented by urea and ethyl butyrate. Another EIS transducer was functionalized with esterase only, thus performing Identity (ID) logic operation for the ethyl butyrate input. Both semiconductor devices assembled in parallel operated as a logically reversible CNOT gate. The present system, despite its simplicity, demonstrated for the first time logically reversible function of the enzyme system transduced electronically with the semiconductor devices. The biomolecular realization of a CNOT gate interfaced with semiconductors is promising for integration into complex biomolecular networks and future biosensor/biomedical applications. KW - Electrolyte–insulator–semiconductor KW - Capacitive field-effect KW - CNOT KW - XOR KW - Enzyme logic gate Y1 - 2017 U6 - https://doi.org/10.1016/j.apmt.2017.08.003 SN - 2352-9407 VL - 9 SP - 266 EP - 270 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Yoshinobu, T. A1 - Ecken, H. A1 - Poghossian, Arshak A1 - Simonis, A. A1 - Iwasaki, H. A1 - Lüth, H. A1 - Schöning, Michael Josef T1 - Constant-current-mode LAPS (CLAPS) for the detection of penicillin JF - Electroanalysis. 13 (2001), H. 8-9 Y1 - 2001 SN - 1040-0397 SP - 733 EP - 736 ER - TY - JOUR A1 - Poghossian, Arshak A1 - Abouzar, Maryam H. A1 - Schöning, Michael Josef T1 - Capacitance–voltage and impedance characteristics of field-effect EIS sensors functionalised with polyelectrolyte multilayers JF - IRBM. 29 (2008), H. 2-3 Y1 - 2008 SN - 1959-0318 SP - 149 EP - 154 ER - TY - JOUR A1 - Poghossian, Arshak A1 - Lüth, H. A1 - Schultze, J. W. A1 - Schöning, Michael Josef T1 - (Bio-)chemical and physical microsensor array using an identical transducer principle JF - Scaling down in electrochemistry : electrochemical micro- and nanosystem technology ; proceedings of the 3rd International Symposium on Electrochemical Microsystem Technologies, Garmisch-Patenkirchen, Germany, 11 - 15 September 2000 / ed. by J. W. Schultz Y1 - 2001 SN - 0-08-044014-2 SP - 243 EP - 249 PB - Elsevier [u.a.] CY - Amsterdam [u.a.] ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Poghossian, Arshak T1 - BioFEDs (field-effect devices) : State-of-the-art and new directions JF - Electroanalysis Y1 - 2006 U6 - https://doi.org/10.1002/elan.200603609 SN - 1521-4109 VL - 18 IS - 19-20 SP - 1893 EP - 1900 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 - https://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 - Rolka, David A1 - Poghossian, Arshak A1 - Schöning, Michael Josef T1 - Integration of a capacitive EIS sensor into a FIA system for pH and penicillin determination JF - Sensors. 4 (2004) Y1 - 2004 SN - 1424-8220 SP - 84 EP - 94 ER - TY - JOUR A1 - Poghossian, Arshak A1 - Schöning, Michael Josef T1 - Detecting Both Physical and (Bio-)Chemical Parameters by Means of ISFET Devices JF - Electroanalysis. 16 (2004), H. 22 Y1 - 2004 SN - 1040-0397 SP - 1863 EP - 1872 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 -