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 - Kurulgan Demirci, Eylem A1 - Demirci, T. A1 - Trzewik, Jürgen A1 - Linder, Peter A1 - Karakulah, G. A1 - Artmann, Gerhard A1 - Sakizli, M. A1 - Temiz Artmann, Aysegül T1 - Genome-Wide Gene Expression Analysis of NIH 3T3 Cell Line Under Mechanical Stimulation JF - Cellular and molecular bioengineering. 4 (2011), H. 1 Y1 - 2011 SN - 1865-5025 SP - 46 EP - 55 PB - Springer CY - Berlin 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 - Thust, M. A1 - Poghossian, Arshak A1 - Schöning, Michael Josef A1 - Naser, S. A1 - Müller-Veggian, Mattea A1 - Kordos, P. A1 - Lüth, H. T1 - Cross-sensitivity of a capacitive penicillin sensor combined with a diffusion barrier JF - Proceedings : The Hague, The Netherlands, September 12 - 15, 1999 / [ed. by M. Bartek]. - Vol 1. Y1 - 1999 SN - 90-76699-02-X N1 - Eurosensors <13, 1999, 's-Gravenhage> ; Eurosensors <13, 1999, The Hague> ; European Conference on Solid-State Transducers <13, 1999, The Hague> SP - 573 EP - 576 CY - The Hague, The Netherlands 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 - 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 -