@article{BaeckerRaueSchusseretal.2012, author = {B{\"a}cker, Matthias and Raue, Markus and Schusser, Sebastian and Jeitner, C. and Breuer, L. and Wagner, P. and Poghossian, Arshak and F{\"o}rster, Arnold and Mang, Thomas and Sch{\"o}ning, Michael Josef}, title = {Microfluidic chip with integrated microvalves based on temperature- and pH-responsive hydrogel thin films}, series = {Physica Status Solidi (a)}, volume = {209}, journal = {Physica Status Solidi (a)}, number = {5}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.201100763}, pages = {839 -- 845}, year = {2012}, abstract = {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.}, language = {en} } @article{BronderPoghossianKeusgenetal.2017, author = {Bronder, Thomas and Poghossian, Arshak and Keusgen, Michael and Sch{\"o}ning, Michael Josef}, title = {Label-free detection of double-stranded DNA molecules with polyelectrolyte-modified capacitive field-effect sensors}, series = {tm - Technisches Messen}, volume = {84}, journal = {tm - Technisches Messen}, number = {10}, publisher = {De Gruyter}, address = {Oldenbourg}, doi = {10.1515/teme-2017-0015}, pages = {628 -- 634}, year = {2017}, abstract = {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.}, language = {en} } @article{JablonskiPoghossianSeverinetal.2021, author = {Jablonski, Melanie and Poghossian, Arshak and Severin, Robin and Keusgen, Michael and Wege, Christian and Sch{\"o}ning, Michael Josef}, title = {Capacitive Field-Effect Biosensor Studying Adsorption of Tobacco Mosaic Virus Particles}, series = {Micromachines}, volume = {12}, journal = {Micromachines}, number = {1}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/mi12010057}, pages = {Artikel 57}, year = {2021}, abstract = {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.}, language = {en} } @article{SchoeningAbouzarPoghossian2009, author = {Sch{\"o}ning, Michael Josef and Abouzar, Maryam H. and Poghossian, Arshak}, title = {pH and ion sensitivity of a field-effect EIS (electrolyte-insulator-semiconductor) sensor covered with polyelectrolyte multilayers}, series = {Journal of Solid State Electrochemistry. 13 (2009), H. 1}, journal = {Journal of Solid State Electrochemistry. 13 (2009), H. 1}, isbn = {1433-0768}, pages = {115 -- 122}, year = {2009}, language = {en} } @article{SchoeningPoghossianYoshinobuetal.2001, author = {Sch{\"o}ning, Michael Josef and Poghossian, Arshak and Yoshinobu, Tatsuo and L{\"u}th, Hans}, title = {Semiconductor-based field-effect structures for chemical sensing}, pages = {188 -- 198}, year = {2001}, language = {en} } @article{KochPoghossianSchoeningetal.2018, author = {Koch, Claudia and Poghossian, Arshak and Sch{\"o}ning, Michael Josef and Wege, Christian}, title = {Penicillin Detection by Tobacco Mosaic Virus-Assisted Colorimetric Biosensors}, series = {Nanotheranostics}, volume = {2}, journal = {Nanotheranostics}, number = {2}, publisher = {Ivyspring}, address = {Sydney}, issn = {2206-7418}, doi = {10.7150/ntno.22114}, pages = {184 -- 196}, year = {2018}, abstract = {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.}, language = {en} } @article{PoghossianThustSchoeningetal.2000, author = {Poghossian, Arshak and Thust, M. and Sch{\"o}ning, Michael Josef and M{\"u}ller-Veggian, Mattea and Kordos, P. and L{\"u}th, H.}, title = {Cross-sensitivity of a capacitive penicillin sensor combined with a diffusion barrier}, series = {Sensors and Actuators B. 68 (2000), H. 1-3}, journal = {Sensors and Actuators B. 68 (2000), H. 1-3}, isbn = {0925-4005}, pages = {260 -- 265}, year = {2000}, language = {en} } @article{SchoeningBrinkmannDemuthetal.2004, author = {Sch{\"o}ning, Michael Josef and Brinkmann, D. and Demuth, C. and Poghossian, Arshak}, title = {CIP (cleaning-in-place)-suitable „non-glass" pH sensor based on a Ta2O5-gate EIS structure}, series = {Digest of technical papers : September 12 - 15, 2004, Rome, Italy, Pontificia Universitas Sancto Thoma Aquinate in Urbe / [conference chairperson: C. Di Natale].}, journal = {Digest of technical papers : September 12 - 15, 2004, Rome, Italy, Pontificia Universitas Sancto Thoma Aquinate in Urbe / [conference chairperson: C. Di Natale].}, address = {Roma}, isbn = {88-7621-282-5}, pages = {857 -- 860}, year = {2004}, language = {en} } @article{PoghossianBerndsenLuethetal.2001, author = {Poghossian, Arshak and Berndsen, Lars and L{\"u}th, Hans and Sch{\"o}ning, Michael Josef}, title = {Novel concepts for flow-rate and flow-direction determination by means of pH-sensitive ISFETs}, series = {Proceedings of SPIE. 4560 (2001)}, journal = {Proceedings of SPIE. 4560 (2001)}, pages = {19 -- 27}, year = {2001}, language = {en} } @article{HonarvarfardGamellaPoghossianetal.2017, author = {Honarvarfard, Elham and Gamella, Maria and Poghossian, Arshak and Sch{\"o}ning, Michael Josef and Katz, Evgeny}, title = {An enzyme-based reversible Controlled NOT (CNOT) logic gate operating on a semiconductor transducer}, series = {Applied Materials Today}, volume = {9}, journal = {Applied Materials Today}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-9407}, doi = {10.1016/j.apmt.2017.08.003}, pages = {266 -- 270}, year = {2017}, abstract = {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.}, language = {en} } @article{YoshinobuEckenPoghossianetal.2001, author = {Yoshinobu, T. and Ecken, H. and Poghossian, Arshak and Simonis, A. and Iwasaki, H. and L{\"u}th, H. and Sch{\"o}ning, Michael Josef}, title = {Constant-current-mode LAPS (CLAPS) for the detection of penicillin}, series = {Electroanalysis. 13 (2001), H. 8-9}, journal = {Electroanalysis. 13 (2001), H. 8-9}, isbn = {1040-0397}, pages = {733 -- 736}, year = {2001}, language = {en} } @article{PoghossianAbouzarSchoening2008, author = {Poghossian, Arshak and Abouzar, Maryam H. and Sch{\"o}ning, Michael Josef}, title = {Capacitance-voltage and impedance characteristics of field-effect EIS sensors functionalised with polyelectrolyte multilayers}, series = {IRBM. 29 (2008), H. 2-3}, journal = {IRBM. 29 (2008), H. 2-3}, isbn = {1959-0318}, pages = {149 -- 154}, year = {2008}, language = {en} } @article{PoghossianLuethSchultzeetal.2001, author = {Poghossian, Arshak and L{\"u}th, H. and Schultze, J. W. and Sch{\"o}ning, Michael Josef}, title = {(Bio-)chemical and physical microsensor array using an identical transducer principle}, series = {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}, journal = {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}, publisher = {Elsevier [u.a.]}, address = {Amsterdam [u.a.]}, isbn = {0-08-044014-2}, pages = {243 -- 249}, year = {2001}, language = {en} } @article{SchoeningPoghossian2006, author = {Sch{\"o}ning, Michael Josef and Poghossian, Arshak}, title = {BioFEDs (field-effect devices) : State-of-the-art and new directions}, series = {Electroanalysis}, volume = {18}, journal = {Electroanalysis}, number = {19-20}, issn = {1521-4109}, doi = {10.1002/elan.200603609}, pages = {1893 -- 1900}, year = {2006}, language = {en} } @article{HuckPoghossianKerroumietal.2014, author = {Huck, Christina and Poghossian, Arshak and Kerroumi, Iman and Schusser, Sebastian and B{\"a}cker, Matthias and Zander, Willi and Schubert, J{\"u}rgen and Buniatyan, Vahe V. and Martirosyan, Norayr W. and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Multiparameter sensor chip with Barium Strontium Titanate as multipurpose material}, series = {Electroanalysis}, volume = {26}, journal = {Electroanalysis}, number = {5}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1521-4109 (E-Journal); 1040-0397 (Print)}, doi = {10.1002/elan.201400076}, pages = {980 -- 987}, year = {2014}, abstract = {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.}, language = {en} } @article{RolkaPoghossianSchoening2004, author = {Rolka, David and Poghossian, Arshak and Sch{\"o}ning, Michael Josef}, title = {Integration of a capacitive EIS sensor into a FIA system for pH and penicillin determination}, series = {Sensors. 4 (2004)}, journal = {Sensors. 4 (2004)}, isbn = {1424-8220}, pages = {84 -- 94}, year = {2004}, language = {en} } @article{PoghossianSchoening2004, author = {Poghossian, Arshak and Sch{\"o}ning, Michael Josef}, title = {Detecting Both Physical and (Bio-)Chemical Parameters by Means of ISFET Devices}, series = {Electroanalysis. 16 (2004), H. 22}, journal = {Electroanalysis. 16 (2004), H. 22}, isbn = {1040-0397}, pages = {1863 -- 1872}, year = {2004}, language = {en} } @article{SiqueiraAbouzarPoghossianetal.2009, author = {Siqueira, Jos{\´e} R. Jr. and Abouzar, Maryam H. and Poghossian, Arshak and Zucolotto, Valtencir and Oliveira, Osvaldo N. Jr. and Sch{\"o}ning, Michael Josef}, title = {Penicillin biosensor based on a capacitive field-effect structure functionalized with a dendrimer/carbon nanotube multilayer}, series = {Biosensors and Bioelectronics. 25 (2009), H. 2}, journal = {Biosensors and Bioelectronics. 25 (2009), H. 2}, isbn = {0956-5663}, pages = {497 -- 501}, year = {2009}, language = {en} } @article{GamellaZakharchenkoGuzetal.2017, author = {Gamella, Maria and Zakharchenko, Andrey and Guz, Nataliia and Masi, Madeline and Minko, Sergiy and Kolpashchikov, Dmitry M. and Iken, Heiko and Poghossian, Arshak and Sch{\"o}ning, Michael Josef and Katz, Evgeny}, title = {DNA computing system activated by electrochemically triggered DNA realease from a polymer-brush-modified electrode array}, series = {Electroanalysis}, volume = {29}, journal = {Electroanalysis}, number = {2}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1521-4109}, doi = {10.1002/elan.201600389}, pages = {398 -- 408}, year = {2017}, abstract = {An array of four independently wired indium tin oxide (ITO) electrodes was used for electrochemically stimulated DNA release and activation of DNA-based Identity, AND and XOR logic gates. Single-stranded DNA molecules were loaded on the mixed poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA)/poly(methacrylic acid) (PMAA) brush covalently attached to the ITO electrodes. The DNA deposition was performed at pH 5.0 when the polymer brush is positively charged due to protonation of tertiary amino groups in PDMAEMA, thus resulting in electrostatic attraction of the negatively charged DNA. By applying electrolysis at -1.0 V(vs. Ag/AgCl reference) electrochemical oxygen reduction resulted in the consumption of hydrogen ions and local pH increase near the electrode surface. The process resulted in recharging the polymer brush to the negative state due to dissociation of carboxylic groups of PMAA, thus repulsing the negatively charged DNA and releasing it from the electrode surface. The DNA release was performed in various combinations from different electrodes in the array assembly. The released DNA operated as input signals for activation of the Boolean logic gates. The developed system represents a step forward in DNA computing, combining for the first time DNA chemical processes with electronic input signals.}, language = {en} } @article{AbouzarPoghossianRazavietal.2008, author = {Abouzar, Maryam H. and Poghossian, Arshak and Razavi, Arash and Besmehn, Astrid and Bijnens, Nathalie and Williams, Oliver A. and Haenen, Ken and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Penicillin detection with nanocrystalline-diamond field-effect sensor}, series = {physica status solidi (a). 205 (2008), H. 9}, journal = {physica status solidi (a). 205 (2008), H. 9}, isbn = {1862-6319}, pages = {2141 -- 2145}, year = {2008}, language = {en} }