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  - CHAP
A1  - Koch, Claudia
A1  - Poghossian, Arshak
A1  - Wege, Christina
A1  - Schöning, Michael Josef
ED  - Wege, Christina
T1  - TMV-Based Adapter Templates for Enhanced Enzyme Loading in Biosensor Applications
T2  - Virus-Derived Nanoparticles for Advanced Technologies
N2  - Nanotubular tobacco mosaic virus (TMV) particles and RNA-free lower-order coat protein (CP) aggregates have been employed as enzyme carriers in different diagnostic layouts and compared for their influence on biosensor performance. In the following, we describe a label-free electrochemical biosensor for improved glucose detection by use of TMV adapters and the enzyme glucose oxidase (GOD). A specific and efficient immobilization of streptavidin-conjugated GOD ([SA]-GOD) complexes on biotinylated TMV nanotubes or CP aggregates was achieved via bioaffinity binding. Glucose sensors with adsorptively immobilized [SA]-GOD, and with [SA]-GOD cross-linked with glutardialdehyde, respectively, were tested in parallel on the same sensor chip. Comparison of these sensors revealed that TMV adapters enhanced the amperometric glucose detection remarkably, conveying highest sensitivity, an extended linear detection range and fastest response times. These results underline a great potential of an integration of virus/biomolecule hybrids with electronic transducers for applications in biosensorics and biochips. Here, we describe the fabrication and use of amperometric sensor chips combining an array of circular Pt electrodes, their loading with GOD-modified TMV nanotubes (and other GOD immobilization methods), and the subsequent investigations of the sensor performance.
KW  - Tobacco mosaic virus (TMV)
KW  - Coat protein
KW  - Enzyme nanocarrier
KW  - Glucose biosensor
KW  - Glucose oxidase
Y1  - 2018
SN  - 978-1-4939-7808-3
U6  - https://doi.org/10.1007/978-1-4939-7808-3
N1  - Methods in Molecular Biology, vol 1776
SP  - 553
EP  - 568
PB  - Humana Press
CY  - New York, NY
ER  - 
TY  - JOUR
A1  - Siqueira, José R. Jr.
A1  - Abouzar, Maryam H.
A1  - Poghossian, Arshak
A1  - Zucolotto, Valtencir
A1  - Oliveira, Osvaldo N. Jr.
A1  - Schöning, Michael Josef
T1  - Penicillin biosensor based on a capacitive field-effect structure functionalized with a dendrimer/carbon nanotube multilayer
JF  - Biosensors and Bioelectronics. 25 (2009), H. 2
Y1  - 2009
SN  - 0956-5663
SP  - 497
EP  - 501
ER  - 
TY  - JOUR
A1  - Gamella, Maria
A1  - Zakharchenko, Andrey
A1  - Guz, Nataliia
A1  - Masi, Madeline
A1  - Minko, Sergiy
A1  - Kolpashchikov, Dmitry M.
A1  - Iken, Heiko
A1  - Poghossian, Arshak
A1  - Schöning, Michael Josef
A1  - Katz, Evgeny
T1  - DNA computing system activated by electrochemically triggered DNA realease from a polymer-brush-modified electrode array
JF  - Electroanalysis
N2  - 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.
Y1  - 2017
U6  - https://doi.org/10.1002/elan.201600389
SN  - 1521-4109
VL  - 29
IS  - 2
SP  - 398
EP  - 408
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Abouzar, Maryam H.
A1  - Poghossian, Arshak
A1  - Razavi, Arash
A1  - Besmehn, Astrid
A1  - Bijnens, Nathalie
A1  - Williams, Oliver A.
A1  - Haenen, Ken
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Penicillin detection with nanocrystalline-diamond field-effect sensor
JF  - physica status solidi (a). 205 (2008), H. 9
Y1  - 2008
SN  - 1862-6319
N1  - Special Issue: Hasselt Diamond Workshop 2008 - SBDD XIII
SP  - 2141
EP  - 2145
ER  - 
TY  - JOUR
A1  - Abouzar, Maryam H.
A1  - Ingebrandt, S.
A1  - Poghossian, Arshak
A1  - Zhang, Y.
A1  - Moritz, W.
A1  - Schöning, Michael Josef
T1  - Field-effect nanoplate capacitive pH sensor based on SOI structure
JF  - Semiconductor micro- and nanoelectronics : Proceedings of the Seventh International Conference , Tsakhcadzor, Armenia July 3-5 2009
Y1  - 2009
SP  - 55
EP  - 58
ER  - 
TY  - JOUR
A1  - Poghossian, Arshak
A1  - Schöning, Michael Josef
T1  - "High-order” hybrid FET module for (bio)chemical and physical sensing
JF  - Integrated analytical systems / ed. by Salvador Alegret
Y1  - 2003
SN  - 0-444-51037-0
SP  - 587
EP  - 623
PB  - Elsevier
CY  - Amsterdam [u.a.]
ER  - 
TY  - JOUR
A1  - Wu, Chunsheng
A1  - Bronder, Thomas
A1  - Poghossian, Arshak
A1  - Werner, Frederik
A1  - Schöning, Michael Josef
T1  - Label-free detection of DNA using light-addressable potentiometric sensor modified with a positively charged polyelectrolyte layer
JF  - Nanoscale
N2  - A multi-spot (16 spots) light-addressable potentiometric sensor (MLAPS) consisting of an Al–p-Si–SiO2 structure modified with a weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)) was applied for the label-free electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization by the intrinsic molecular charge for the first time. To achieve a preferentially flat orientation of DNA strands and thus, to reduce the distance between the DNA charge and MLAPS surface, the negatively charged probe single-stranded DNAs (ssDNA) were electrostatically adsorbed onto the positively charged PAH layer using a simple layer-by-layer (LbL) technique. In this way, more DNA charge can be positioned within the Debye length, yielding a higher sensor signal. The surface potential changes in each spot induced due to the surface modification steps (PAH adsorption, probe ssDNA immobilization, hybridization with complementary target DNA (cDNA), non-specific adsorption of mismatched ssDNA) were determined from the shifts of photocurrent–voltage curves along the voltage axis. A high sensor signal of 83 mV was registered after immobilization of probe ssDNA onto the PAH layer. The hybridization signal increases from 5 mV to 32 mV with increasing the concentration of cDNA from 0.1 nM to 5 μM. In contrast, a small signal of 5 mV was recorded in the case of non-specific adsorption of fully mismatched ssDNA (5 μM). The obtained results demonstrate the potential of the MLAPS in combination with the simple and rapid LbL immobilization technique as a promising platform for the future development of multi-spot light-addressable label-free DNA chips with direct electrical readout.
Y1  - 2015
U6  - https://doi.org/10.1039/C4NR07225A
VL  - 14
IS  - 7
SP  - 6143
EP  - 6150
PB  - Royal Society of Chemistry (RSC)
CY  - Cambridge
ER  - 
TY  - JOUR
A1  - Beging, Stefan
A1  - Mlynek, Daniela
A1  - Hataihimakul, Sudkanung
A1  - Poghossian, Arshak
A1  - Baldsiefen, Gerhard
A1  - Busch, Heinz
A1  - Laube, Norbert
A1  - Kleinen, Lisa
A1  - Schöning, Michael Josef
T1  - Field-effect calcium sensor for the determination of the risk of urinary stone  formation
JF  - Sensors and Actuators B: Chemical. 144 (2010), H. 2
Y1  - 2010
N1  - 22nd International Conference on Eurosensors - Dresden, Germany, 7-10 September 2008 ; Eurosensors ; (22, 2008, Dresden)
SP  - 374
EP  - 379
ER  - 
TY  - JOUR
A1  - Buniatyan, V.
A1  - Huck, Christina
A1  - Poghossian, Arshak
A1  - Aroutiounian, V. M.
A1  - Schöning, Michael Josef
T1  - BaxSr1-x TiO3/pc-Si heterojunction
JF  - Armenian journal of physics
Y1  - 2013
SN  - 1829-1171
VL  - 6
IS  - 4
SP  - 177
EP  - 187
PB  - National Academy of Sciences of Armenia
CY  - Yerevan
ER  - 
TY  - JOUR
A1  - Yoshinobu, T.
A1  - Ecken, H.
A1  - Poghossian, Arshak
A1  - Lüth, H.
A1  - Iwasaki, H.
A1  - Schöning, Michael Josef
T1  - Alternative sensor materials for light-addressable potentiometric sensors
JF  - Sensors and Actuators B. 76 (2001), H. 1-3
Y1  - 2001
SN  - 0925-4005
SP  - 388
EP  - 392
ER  - 
TY  - JOUR
A1  - Poghossian, Arshak
A1  - Abouzar, Maryam H.
A1  - Sakkari, M.
A1  - Kassab, T.
A1  - Han, Y.
A1  - Ingebrandt, S.
A1  - Offenhäusser, A.
A1  - Schöning, Michael Josef
T1  - Field-effect sensors for monitoring the layer-by-layer adsorption of charged macromolecules
JF  - Sensors and Actuators B: Chemical. 118 (2006), H. 1-2
Y1  - 2006
SN  - 0925-4005
N1  - Eurosensors XIX - Eurosensors XIX - The 19th European Conference on Solid-State Transducers
SP  - 163
EP  - 170
ER  - 
TY  - JOUR
A1  - Krämer, Melina
A1  - Pita, Marcos
A1  - Zhou, Jian
A1  - Ornatska, Maryna
A1  - Poghossian, Arshak
A1  - Schöning, Michael Josef
A1  - Katz, Evgeny
T1  - Coupling of Biocomputing Systems with Electronic Chips: Electronic Interface for Transduction of Biochemical Information
JF  - Journal of Physical Chemistry C: Nanomaterials and Interfaces. 113 (2009), H. 6
Y1  - 2009
SN  - 1932-7455
SP  - 2573
EP  - 2579
PB  - American Cemical Society
CY  - Washington, DC
ER  - 
TY  - JOUR
A1  - Wu, Chunsheng
A1  - Bronder, Thomas
A1  - Poghossian, Arshak
A1  - Werner, Frederik
A1  - Bäcker, Matthias
A1  - Schöning, Michael Josef
T1  - Label-free electrical detection of DNA with a multi-spot LAPS: First step towards light-addressable DNA chips
JF  - Physica status solidi A : Applications and materials science
N2  - A multi-spot (4 × 4 spots) light-addressable potentiometric sensor (MLAPS) consisting of an Al–p-Si–SiO2 structure has been applied for the label-free electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization by the intrinsic molecular charge for the first time. Single-stranded probe ssDNA molecules (20 bases) were covalently immobilized onto the silanized SiO2 gate surface. The unspecific adsorption of mismatch ssDNA on the MLAPS gate surface was blocked by bovine serum albumin molecules. To reduce the screening effect and to achieve a high sensor signal, the measurements were performed in a low ionic-strength solution. The photocurrent–voltage (I–V) curves were simultaneously recorded on all 16 spots after each surface functionalization step. Large shifts of I–V curves of 25 mV were registered after the DNA immobilization and hybridization event. In contrast, a small potential shift (∼5 mV) was observed in case of mismatch ssDNA, revealing good specificity of the sensor. The obtained results demonstrate the potential of the MLAPS as promising transducer platform for the multi-spot label-free electrical detection of DNA molecules by their intrinsic molecular charge.
Y1  - 2014
U6  - https://doi.org/10.1002/pssa.201330442
SN  - 1521-396X (E-Journal); 1862-6319 (E-Journal); 0031-8965 (Print); 1862-6300 (Print)
VL  - 211
IS  - 6
SP  - 1423
EP  - 1428
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - CHAP
A1  - Näther, Niko
A1  - Poghossian, Arshak
A1  - Platen, J.
A1  - Yoshinobu, T.
A1  - Koudelka-Hep, M.
A1  - Schöning, Michael Josef
T1  - Multi-parameter sensing of both physical and (bio-)chemical quantities using the same transducer principle
T2  - Biochemical sensing utilisation of micro- and nanotechnologies : Warsaw, [23rd - 26th] November 2005 / ed. by M. Mascini ...
Y1  - 2006
SP  - 172
EP  - 181
CY  - Warsaw
ER  - 
TY  - JOUR
A1  - Poghossian, Arshak
A1  - Jablonski, Melanie
A1  - Molinnus, Denise
A1  - Wege, Christina
A1  - Schöning, Michael Josef
T1  - Field-Effect Sensors for Virus Detection: From Ebola to SARS-CoV-2 and Plant Viral Enhancers
JF  - Frontiers in Plant Science
N2  - Coronavirus disease 2019 (COVID-19) is a novel human infectious disease provoked by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Currently, no specific vaccines or drugs against COVID-19 are available. Therefore, early diagnosis and treatment are essential in order to slow the virus spread and to contain the disease outbreak. Hence, new diagnostic tests and devices for virus detection in clinical samples that are faster, more accurate and reliable, easier and cost-efficient than existing ones are needed. Due to the small sizes, fast response time, label-free operation without the need for expensive and time-consuming labeling steps, the possibility of real-time and multiplexed measurements, robustness and portability (point-of-care and on-site testing), biosensors based on semiconductor field-effect devices (FEDs) are one of the most attractive platforms for an electrical detection of charged biomolecules and bioparticles by their intrinsic charge. In this review, recent advances and key developments in the field of label-free detection of viruses (including plant viruses) with various types of FEDs are presented. In recent years, however, certain plant viruses have also attracted additional interest for biosensor layouts: Their repetitive protein subunits arranged at nanometric spacing can be employed for coupling functional molecules. If used as adapters on sensor chip surfaces, they allow an efficient immobilization of analyte-specific recognition and detector elements such as antibodies and enzymes at highest surface densities. The display on plant viral bionanoparticles may also lead to long-time stabilization of sensor molecules upon repeated uses and has the potential to increase sensor performance substantially, compared to conventional layouts. This has been demonstrated in different proof-of-concept biosensor devices. Therefore, richly available plant viral particles, non-pathogenic for animals or humans, might gain novel importance if applied in receptor layers of FEDs. These perspectives are explained and discussed with regard to future detection strategies for COVID-19 and related viral diseases.
Y1  - 2020
U6  - https://doi.org/10.3389/fpls.2020.598103
VL  - 11
IS  - Article 598103
SP  - 1
EP  - 14
PB  - Frontiers
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Schusser, Sebastian
A1  - Leinhos, Marcel
A1  - Bäcker, Matthias
A1  - Poghossian, Arshak
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Impedance spectroscopy: A tool for real-time in situ monitoring of the degradation of biopolymers
JF  - Physica Status Solidi (A)
N2  - Investigation of the degradation kinetics of biodegradable polymers is essential for the development of implantable biomedical devices with predicted biodegradability. In this work, an impedimetric sensor has been applied for real-time and in situ monitoring of degradation processes of biopolymers. The sensor consists of two platinum thin-film electrodes covered by a polymer film to be studied. The benchmark biomedical polymer poly(D,L-lactic acid) (PDLLA) was used as a model system. PDLLA films were deposited on the sensor structure from a polymer solution by using the spin-coating method. The degradation kinetics of PDLLA films have been studied in alkaline solutions of pH 9 and 12 by means of an impedance spectroscopy (IS) method. Any changes in a polymer capacitance/resistance induced by water uptake and/or polymer degradation will modulate the global impedance of the polymer-covered sensor that can be used as an indicator of the polymer degradation. The degradation rate can be evaluated from the time-dependent impedance spectra. As expected, a faster degradation has been observed for PDLLA films exposed to pH 12 solution.
Y1  - 2013
U6  - https://doi.org/10.1002/pssa.201200941
SN  - 1521-396X ; 0031-8965
VL  - 210
IS  - 5
SP  - 905
EP  - 910
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - BOOK
A1  - Schöning, Michael Josef
A1  - Poghossian, Arshak
T1  - Label-free biosensing: advanced materials, devices and applications
Y1  - 2018
SN  - 978-3-319-75219-8
PB  - Springer
CY  - Cham
ER  - 
TY  - JOUR
A1  - Karschuck, Tobias
A1  - Poghossian, Arshak
A1  - Ser, Joey
A1  - Tsokolakyan, Astghik
A1  - Achtsnicht, Stefan
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Capacitive model of enzyme-modified field-effect biosensors: Impact of enzyme coverage
JF  - Sensors and Actuators B: Chemical
N2  - Electrolyte-insulator-semiconductor capacitors (EISCAP) belong to field-effect sensors having an attractive transducer architecture for constructing various biochemical sensors. In this study, a capacitive model of enzyme-modified EISCAPs has been developed and the impact of the surface coverage of immobilized enzymes on its capacitance-voltage and constant-capacitance characteristics was studied theoretically and experimentally. The used multicell arrangement enables a multiplexed electrochemical characterization of up to sixteen EISCAPs. Different enzyme coverages have been achieved by means of parallel electrical connection of bare and enzyme-covered single EISCAPs in diverse combinations. As predicted by the model, with increasing the enzyme coverage, both the shift of capacitance-voltage curves and the amplitude of the constant-capacitance signal increase, resulting in an enhancement of analyte sensitivity of the EISCAP biosensor. In addition, the capability of the multicell arrangement with multi-enzyme covered EISCAPs for sequentially detecting multianalytes (penicillin and urea) utilizing the enzymes penicillinase and urease has been experimentally demonstrated and discussed.
KW  - Field-effect biosensor
KW  - Capacitive model
KW  - Enzyme coverage
KW  - Multianalyte detection
KW  - Penicillin
Y1  - 2024
U6  - https://doi.org/10.1016/j.snb.2024.135530
SN  - 0925-4005 (Print)
SN  - 1873-3077 (Online)
N1  - Corresponding Author: Michael J. Schöning
VL  - 408
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Özsoylu, Dua
A1  - Kizildag, Sefa
A1  - Schöning, Michael Josef
A1  - Wagner, Torsten
T1  - Differential chemical imaging of extracellular acidification within microfluidic channels using a plasma-functionalized light-addressable potentiometric sensor (LAPS)
JF  - Physics in Medicine
N2  - Extracellular acidification is a basic indicator for alterations in two vital metabolic pathways: glycolysis and cellular respiration. Measuring these alterations by monitoring extracellular acidification using cell-based biosensors such as LAPS plays an important role in studying these pathways whose disorders are associated with numerous diseases including cancer. However, the surface of the biosensors must be specially tailored to ensure high cell compatibility so that cells can represent more in vivo-like behavior, which is critical to gain more realistic in vitro results from the analyses, e.g., drug discovery experiments. In this work, O2 plasma patterning on the LAPS surface is studied to enhance surface features of the sensor chip, e.g., wettability and biofunctionality. The surface treated with O2 plasma for 30 s exhibits enhanced cytocompatibility for adherent CHO–K1 cells, which promotes cell spreading and proliferation. The plasma-modified LAPS chip is then integrated into a microfluidic system, which provides two identical channels to facilitate differential measurements of the extracellular acidification of CHO–K1 cells. To the best of our knowledge, it is the first time that extracellular acidification within microfluidic channels is quantitatively visualized as differential (bio-)chemical images.
Y1  - 2020
U6  - https://doi.org/10.1016/j.phmed.2020.100030
SN  - 2352-4510
VL  - 10
IS  - 100030
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Engelmann, Ulrich M.
A1  - Pourshahidi, Mohammad Ali
A1  - Shalaby, Ahmed
A1  - Krause, Hans-Joachim
T1  - Probing particle size dependency of frequency mixing magnetic detection with dynamic relaxation simulation
JF  - Journal of Magnetism and Magnetic Materials
N2  - Biomedical applications of magnetic nanoparticles (MNP) fundamentally rely on the particles’ magnetic relaxation as a response to an alternating magnetic field. The magnetic relaxation complexly depends on the interplay of MNP magnetic and physical properties with the applied field parameters. It is commonly accepted that particle core size is a major contributor to signal generation in all the above applications, however, most MNP samples comprise broad distribution spanning  nm and more. Therefore, precise knowledge of the exact contribution of individual core sizes to signal generation is desired for optimal MNP design generally for each application. Specifically, we present a magnetic relaxation simulation-driven analysis of experimental frequency mixing magnetic detection (FMMD) for biosensing to quantify the contributions of individual core size fractions towards signal generation. Applying our method to two different experimental MNP systems, we found the most dominant contributions from approx. 20 nm sized particles in the two independent MNP systems. Additional comparison between freely suspended and immobilized MNP also reveals insight in the MNP microstructure, allowing to use FMMD for MNP characterization, as well as to further fine-tune its applicability in biosensing.
Y1  - 2022
U6  - https://doi.org/10.1016/j.jmmm.2022.169965
SN  - 0304-8853
VL  - 563
IS  - In progress, Art. No. 169965
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Achtsnicht, Stefan
A1  - Tödter, Julia
A1  - Niehues, Julia
A1  - Telöken, Matthias
A1  - Offenhäusser, Andreas
A1  - Krause, Hans-Joachim
A1  - Schröper, Florian
T1  - 3D printed modular immunofiltration columns for frequency mixing-based multiplex magnetic immunodetection
JF  - Sensors
N2  - For performing point-of-care molecular diagnostics, magnetic immunoassays constitute a promising alternative to established enzyme-linked immunosorbent assays (ELISA) because they are fast, robust and sensitive. Simultaneous detection of multiple biomolecular targets from one body fluid sample is desired. The aim of this work is to show that multiplex magnetic immunodetection based on magnetic frequency mixing by means of modular immunofiltration columns prepared for different targets is feasible. By calculations of the magnetic response signal, the required spacing between the modules was determined. Immunofiltration columns were manufactured by 3D printing and antibody immobilization was performed in a batch approach. It was shown experimentally that two different target molecules in a sample solution could be individually detected in a single assaying step with magnetic measurements of the corresponding immobilization filters. The arrangement order of the filters and of a negative control did not influence the results. Thus, a simple and reliable approach to multi-target magnetic immunodetection was demonstrated.
Y1  - 2019
U6  - https://doi.org/10.3390/s19010148
SN  - 1424-8220
VL  - 19
IS  - 1
PB  - MDPI
CY  - Basel
ER  - 
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  - 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  - 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  - Falkenberg, Fabian
A1  - Bott, Michael
A1  - Bongaerts, Johannes
A1  - Siegert, Petra
T1  - Phylogenetic survey of the subtilase family and a data-mining-based search for new subtilisins from Bacillaceae
JF  - Frontiers in Microbiology
N2  - The subtilase family (S8), a member of the clan SB of serine proteases are ubiquitous in all kingdoms of life and fulfil different physiological functions. Subtilases are divided in several groups and especially subtilisins are of interest as they are used in various industrial sectors. Therefore, we searched for new subtilisin sequences of the family Bacillaceae using a data mining approach. The obtained 1,400 sequences were phylogenetically classified in the context of the subtilase family. This required an updated comprehensive overview of the different groups within this family. To fill this gap, we conducted a phylogenetic survey of the S8 family with characterised holotypes derived from the MEROPS database. The analysis revealed the presence of eight previously uncharacterised groups and 13 subgroups within the S8 family. The sequences that emerged from the data mining with the set filter parameters were mainly assigned to the subtilisin subgroups of true subtilisins, high-alkaline subtilisins, and phylogenetically intermediate subtilisins and represent an excellent source for new subtilisin candidates.
Y1  - 2022
U6  - https://doi.org/10.3389/fmicb.2022.1017978
SN  - 1664-302X
VL  - 2022
IS  - 13
PB  - Frontiers
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Welden, Melanie
A1  - Severins, Robin
A1  - Poghossian, Arshak
A1  - Wege, Christina
A1  - Bongaerts, Johannes
A1  - Siegert, Petra
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Detection of acetoin and diacetyl by a tobacco mosaic virus-assisted field-effect biosensor
JF  - Chemosensors
N2  - Acetoin and diacetyl have a major impact on the flavor of alcoholic beverages such as wine or beer. Therefore, their measurement is important during the fermentation process. Until now, gas chromatographic techniques have typically been applied; however, these require expensive laboratory equipment and trained staff, and do not allow for online monitoring. In this work, a capacitive electrolyte–insulator–semiconductor sensor modified with tobacco mosaic virus (TMV) particles as enzyme nanocarriers for the detection of acetoin and diacetyl is presented. The enzyme acetoin reductase from Alkalihalobacillus clausii DSM 8716ᵀ is immobilized via biotin–streptavidin affinity, binding to the surface of the TMV particles. The TMV-assisted biosensor is electrochemically characterized by means of leakage–current, capacitance–voltage, and constant capacitance measurements. In this paper, the novel biosensor is studied regarding its sensitivity and long-term stability in buffer solution. Moreover, the TMV-assisted capacitive field-effect sensor is applied for the detection of diacetyl for the first time. The measurement of acetoin and diacetyl with the same sensor setup is demonstrated. Finally, the successive detection of acetoin and diacetyl in buffer and in diluted beer is studied by tuning the sensitivity of the biosensor using the pH value of the measurement solution.
Y1  - 2022
U6  - https://doi.org/10.3390/chemosensors10060218
SN  - 2227-9040
N1  - This article belongs to the Special Issue "Nanostructured Devices for Biochemical Sensing"
VL  - 10
IS  - 6
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Karschuck, Tobias
A1  - Kaulen, Corinna
A1  - Poghossian, Arshak
A1  - Wagner, Patrick H.
A1  - Schöning, Michael Josef
T1  - Gold nanoparticle-modified capacitive field-effect sensors: Studying the surface density of nanoparticles and coupling of charged polyelectrolyte macromolecules
JF  - Electrochemical Science Advances
N2  - The coupling of ligand-stabilized gold nanoparticles with field-effect devices offers new possibilities for label-free biosensing. In this work, we study the immobilization of aminooctanethiol-stabilized gold nanoparticles (AuAOTs) on the silicon dioxide surface of a capacitive field-effect sensor. The terminal amino group of the AuAOT is well suited for the functionalization with biomolecules. The attachment of the positively-charged AuAOTs on a capacitive field-effect sensor was detected by direct electrical readout using capacitance-voltage and constant capacitance measurements. With a higher particle density on the sensor surface, the measured signal change was correspondingly more pronounced. The results demonstrate the ability of capacitive field-effect sensors for the non-destructive quantitative validation of nanoparticle immobilization. In addition, the electrostatic binding of the polyanion polystyrene sulfonate to the AuAOT-modified sensor surface was studied as a model system for the label-free detection of charged macromolecules. Most likely, this approach can be transferred to the label-free detection of other charged molecules such as enzymes or antibodies.
KW  - polystyrene sulfonate
KW  - gold nanoparticles
KW  - field-effect sensor
KW  - detection of charged macromolecules
KW  - capacitive EIS sensor
Y1  - 2021
U6  - https://doi.org/10.1002/elsa.202100179
SN  - 0938-5193
VL  - 2
IS  - 5
PB  - Wiley-VCH
CY  - Weinheim
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  - Poghossian, Arshak
A1  - Welden, Rene
A1  - Buniatyan, Vahe V.
A1  - Schöning, Michael Josef
T1  - An Array of On-Chip Integrated, Individually Addressable Capacitive Field-Effect Sensors with Control Gate: Design and Modelling
JF  - Sensors
N2  - The on-chip integration of multiple biochemical sensors based on field-effect electrolyte-insulator-semiconductor capacitors (EISCAP) is challenging due to technological difficulties in realization of electrically isolated EISCAPs on the same Si chip. In this work, we present a new simple design for an array of on-chip integrated, individually electrically addressable EISCAPs with an additional control gate (CG-EISCAP). The existence of the CG enables an addressable activation or deactivation of on-chip integrated individual CG-EISCAPs by simple electrical switching the CG of each sensor in various setups, and makes the new design capable for multianalyte detection without cross-talk effects between the sensors in the array. The new designed CG-EISCAP chip was modelled in so-called floating/short-circuited and floating/capacitively-coupled setups, and the corresponding electrical equivalent circuits were developed. In addition, the capacitance-voltage curves of the CG-EISCAP chip in different setups were simulated and compared with that of a single EISCAP sensor. Moreover, the sensitivity of the CG-EISCAP chip to surface potential changes induced by biochemical reactions was simulated and an impact of different parameters, such as gate voltage, insulator thickness and doping concentration in Si, on the sensitivity has been discussed.
KW  - equivalent circuit
KW  - multianalyte detection
KW  - control gate
KW  - on-chip integrated addressable EISCAP sensors
KW  - capacitive field-effect sensor
Y1  - 2021
U6  - https://doi.org/10.3390/s21186161
SN  - 1424-8220
N1  - This article belongs to the Special Issue "Field-Effect Sensors: From pH Sensing to Biosensing"
VL  - 21
IS  - 18
SP  - 17
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Vahidpour, Farnoosh
A1  - Guthman, Eric
A1  - Arreola, Julia
A1  - Alghazali, Yousef H. M.
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
T1  - Assessment of Various Process Parameters for Optimized Sterilization Conditions Using a Multi-Sensing Platform
JF  - Foods
N2  - In this study, an online multi-sensing platform was engineered to simultaneously evaluate various process parameters of food package sterilization using gaseous hydrogen peroxide (H₂O₂). The platform enabled the validation of critical aseptic parameters. In parallel, one series of microbiological count reduction tests was performed using highly resistant spores of B. atrophaeus DSM 675 to act as the reference method for sterility validation. By means of the multi-sensing platform together with microbiological tests, we examined sterilization process parameters to define the most effective conditions with regards to the highest spore kill rate necessary for aseptic packaging. As these parameters are mutually associated, a correlation between different factors was elaborated. The resulting correlation indicated the need for specific conditions regarding the applied H₂O₂ gas temperature, the gas flow and concentration, the relative humidity and the exposure time. Finally, the novel multi-sensing platform together with the mobile electronic readout setup allowed for the online and on-site monitoring of the sterilization process, selecting the best conditions for sterility and, at the same time, reducing the use of the time-consuming and costly microbiological tests that are currently used in the food package industry.
KW  - spore kill rate
KW  - sterility
KW  - aseptic parameters
KW  - multi-sensing platform
KW  - gaseous hydrogen peroxide
Y1  - 2022
U6  - https://doi.org/10.3390/foods11050660
SN  - 2304-8158
N1  - This article belongs to the Special Issue "Sensors and Biosensors Application for Food Industries"
VL  - 11
IS  - 5
PB  - MDPI
CY  - Basel
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  - Abulnaga, El-Hussiny
A1  - Pinkenburg, Olaf
A1  - Schiffels, Johannes
A1  - E-Refai, Ahmed
A1  - Buckel, Wolfgang
A1  - Selmer, Thorsten
T1  - Effect of an Oxygen-Tolerant Bifurcating Butyryl Coenzyme A Dehydrogenase/Electron-Transferring Flavoprotein Complex from Clostridium difficile on Butyrate Production in Escherichia coli
JF  - Journal of bacteriology
Y1  - 2013
SN  - 1098-5530 [E-Journal]
SN  - 0021-9193 [Print]
VL  - 195
IS  - 16
SP  - 3704
EP  - 3713
ER  - 
TY  - JOUR
A1  - Bronder, Thomas
A1  - Jessing, Max P.
A1  - Poghossian, Arshak
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Detection of PCR-Amplified Tuberculosis DNA Fragments with Polyelectrolyte-Modified Field-Effect Sensors
JF  - Analytical Chemistry
N2  - Field-effect-based electrolyte-insulator-semiconductor (EIS) sensors were modified with a bilayer of positively charged weak polyelectrolyte (poly(allylamine hydrochloride) (PAH)) and probe single-stranded DNA (ssDNA) and are used for the detection of complementary single-stranded target DNA (cDNA) in different test solutions. The sensing mechanism is based on the detection of the intrinsic molecular charge of target cDNA molecules after the hybridization event between cDNA and immobilized probe ssDNA. The test solutions contain synthetic cDNA oligonucleotides (with a sequence of tuberculosis mycobacteria genome) or PCR-amplified DNA (which origins from a template DNA strand that has been extracted from Mycobacterium avium paratuberculosis-spiked human sputum samples), respectively. Sensor responses up to 41 mV have been measured for the test solutions with DNA, while only small signals of ∼5 mV were detected for solutions without DNA. The lower detection limit of the EIS sensors was ∼0.3 nM, and the sensitivity was ∼7.2 mV/decade. Fluorescence experiments using SybrGreen I fluorescence dye support the electrochemical results.
Y1  - 2018
U6  - https://doi.org/10.1021/acs.analchem.8b01807
SN  - 0003-2700
VL  - 90
IS  - 12
SP  - 7747
EP  - 7753
PB  - ACS Publications
CY  - Washington, DC
ER  - 
TY  - JOUR
A1  - Jildeh, Zaid B.
A1  - Oberländer, Jan
A1  - Kirchner, Patrick
A1  - Keusgen, Michael
A1  - Wagner, Patrick H.
A1  - Schöning, Michael Josef
T1  - Experimental and Numerical Analyzes of a Sensor Based on Interdigitated Electrodes for Studying Microbiological Alterations
JF  - physica status solidi (a): applications and materials science
N2  - In this work, a cell-based biosensor to evaluate the sterilization efficacy of hydrogen peroxide vapor sterilization processes is characterized. The transducer of the biosensor is based on interdigitated gold electrodes fabricated on an inert glass substrate. Impedance spectroscopy is applied to evaluate the sensor behavior and the alteration of test microorganisms due to the sterilization process. These alterations are related to changes in relative permittivity and electrical conductivity of the bacterial spores. Sensor measurements are conducted with and without bacterial spores (Bacillus atrophaeus), as well as after an industrial sterilization protocol. Equivalent two-dimensional numerical models based on finite element method of the periodic finger structures of the interdigitated gold electrodes are designed and validated using COMSOL® Multiphysics software by the application of known dielectric properties. The validated models are used to compute the electrical properties at different sensor states (blank, loaded with spores, and after sterilization). As a final result, we will derive and tabulate the frequency-dependent electrical parameters of the spore layer using a novel model that combines experimental data with numerical optimization techniques.
Y1  - 2018
U6  - https://doi.org/10.1002/pssa.201700920
SN  - 1862-6319
VL  - 215
IS  - 15
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Molinnus, Denise
A1  - Poghossian, Arshak
A1  - Keusgen, Michael
A1  - Katz, Evgeny
A1  - Schöning, Michael Josef
T1  - Coupling of Biomolecular Logic Gates with Electronic Transducers: From Single Enzyme Logic Gates to Sense/Act/Treat Chips
JF  - Electroanalysis
N2  - The integration of biomolecular logic principles with electronic transducers allows designing novel digital biosensors with direct electrical output, logically triggered drug-release, and closed-loop sense/act/treat systems. This opens new opportunities for advanced personalized medicine in the context of theranostics. In the present work, we will discuss selected examples of recent developments in the field of interfacing enzyme logic gates with electrodes and semiconductor field-effect devices. Special attention is given to an enzyme OR/Reset logic gate based on a capacitive field-effect electrolyte-insulator-semiconductor sensor modified with a multi-enzyme membrane. Further examples are a digital adrenaline biosensor based on an AND logic gate with binary YES/NO output and an integrated closed-loop sense/act/treat system comprising an amperometric glucose sensor, a hydrogel actuator, and an insulin (drug) sensor.
Y1  - 2017
U6  - https://doi.org/10.1002/elan.201700208
SN  - 1521-4109
VL  - 29
IS  - 8
SP  - 1840
EP  - 1849
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - CHAP
A1  - Schöning, Michael Josef
A1  - Wagner, Torsten
A1  - Poghossian, Arshak
A1  - Miyamoto, K.I.
A1  - Werner, C.F.
A1  - Krause, S.
A1  - Yoshinobu, T.
T1  - Light-addressable potentiometric sensors for (bio-)chemical sensing and imaging
T2  - Encyclopedia of Interfacial Chemistry: Surface Science and Electrochemistry. Vol. 7
Y1  - 2018
SN  - 9780128097397
SP  - 295
EP  - 308
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Poghossian, Arshak
A1  - Yoshinobu, Tatsuo
A1  - Simonis, A.
A1  - Ecken, H.
A1  - Lüth, Hans
A1  - Schöning, Michael Josef
T1  - Penicillin detection by means of field-effect based sensors: EnFET, capacitive EIS sensor or LAPS?
JF  - Sensors and Actuators B. 78 (2001), H. 1-3
Y1  - 2001
SN  - 0925-4005
SP  - 237
EP  - 242
ER  - 
TY  - JOUR
A1  - Poghossian, Arshak
A1  - Schöning, Michael Josef
T1  - Chemical and biological field-effect sensors for liquids – a status report
JF  - Handbook of biosensors and biochips / ed. Robert S. Marks ... Bd. 1
Y1  - 2007
SN  - 978-0-470-01905-4
SP  - 395
EP  - 412
PB  - Wiley
CY  - Chichester
ER  - 
TY  - JOUR
A1  - Poghossian, Arshak
A1  - Weil, M.
A1  - Cherstvy, A. G.
A1  - Schöning, Michael Josef
T1  - Electrical monitoring of polyelectrolyte multilayer formation by means of capacitive field-effect devices
JF  - Analytical and bioanalytical chemistry
N2  - The semiconductor field-effect platform represents a powerful tool for detecting the adsorption and binding of charged macromolecules with direct electrical readout. In this work, a capacitive electrolyte–insulator–semiconductor (EIS) field-effect sensor consisting of an Al-p-Si-SiO2 structure has been applied for real-time in situ electrical monitoring of the layer-by-layer formation of polyelectrolyte (PE) multilayers (PEM). The PEMs were deposited directly onto the SiO2 surface without any precursor layer or drying procedures. Anionic poly(sodium 4-styrene sulfonate) and cationic weak polyelectrolyte poly(allylamine hydrochloride) have been chosen as a model system. The effect of the ionic strength of the solution, polyelectrolyte concentration, number and polarity of the PE layers on the characteristics of the PEM-modified EIS sensors have been studied by means of capacitance–voltage and constant-capacitance methods. In addition, the thickness, surface morphology, roughness and wettabilityof the PE mono- and multilayers have been characterised by ellipsometry, atomic force microscopy and water contact-angle methods, respectively. To explain potential oscillations on the gate surface and signal behaviour of the capacitive field-effect EIS sensor modified with a PEM, a simplified electrostatic model that takes into account the reduced electrostatic screening of PE charges by mobile ions within the PEM has been proposed and discussed.
Y1  - 2013
U6  - https://doi.org/10.1007/s00216-013-6951-9
SN  - 1432-1130 ; 1618-2642
VL  - 405
IS  - 20
SP  - 6425
EP  - 6436
PB  - Springer
CY  - Berlin
ER  - 
TY  - CHAP
A1  - Wu, Chunsheng
A1  - Bronder, Thomas
A1  - Poghossian, Arshak
A1  - Schöning, Michael Josef
T1  - DNA-hybridization detection using light-addressable potentiometric sensor modified with gold layer
T2  - Sensoren und Messsysteme 2014 ; Beiträge der 17. GMA/ITG-Fachtagung vom 3. bis 4. Juni 2014 in Nürnberg. (ITG-Fachbericht ; 250)
Y1  - 2014
SN  - 978-3-8007-3622-5
SP  - 1
EP  - 4
PB  - VDE-Verl.
CY  - Düsseldorf
ER  - 
TY  - CHAP
A1  - Huck, Christina
A1  - Poghossian, Arshak
A1  - Buniatyan, V.
A1  - Schöning, Michael Josef
T1  - Multi-parameter detection for supporting monitoring and control of biogas processes in agriculture
T2  - Sensoren und Messsysteme 2014 ; Beiträge der 17. GMA/ITG-Fachtagung vom 3. bis 4. Juni 2014 in Nürnberg. (ITG-Fachbericht ; 250)
Y1  - 2014
SN  - 978-3-8007-3622-5
SP  - 1
EP  - 5
PB  - VDE-Verl.
CY  - Berlin
ER  - 
TY  - CHAP
A1  - Schöning, Michael Josef
A1  - Poghossian, Arshak
A1  - Glück, Olaf
A1  - Thust, Marion
T1  - Electrochemical methods for the determination of chemical variables in aqueous media
T2  - Measurement, instrumentation, and sensors handbook / ed. by John G. Webster [u.a.] Vol. 2 : Electromagnetic, optical, radiation, chemical, and biomedical measurement
Y1  - 2014
SN  - 978-1-4398-4891-3
SP  - 55-1
EP  - 55-54
PB  - CRC Pr.
CY  - Boca Raton, Fla.
ER  - 
TY  - JOUR
A1  - Molinnus, Denise
A1  - Bäcker, Matthias
A1  - Siegert, Petra
A1  - Willenberg, H.
A1  - Poghossian, Arshak
A1  - Keusgen, M.
A1  - Schöning, Michael Josef
T1  - Detection of Adrenaline Based on Substrate Recycling Amplification
JF  - Procedia Engineering
N2  - An amperometric enzyme biosensor has been applied for the detection of adrenaline. The adrenaline biosensor has been prepared by modification of an oxygen electrode with the enzyme laccase that operates at a broad pH range between pH 3.5 to pH 8. The enzyme molecules were immobilized via cross-linking with glutaraldehyde. The sensitivity of the developed adrenaline biosensor in different pH buffer solutions has been studied.
Y1  - 2015
U6  - https://doi.org/10.1016/j.proeng.2015.08.708
SN  - 1877-7058
N1  - Eurosensors 2015
VL  - 120
SP  - 540
EP  - 543
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Abouzar, Maryam H.
A1  - Poghossian, Arshak
A1  - Cherstvy, Andrey G.
A1  - Pedraza, Angela M.
A1  - Ingebrandt, Sven
A1  - Schöning, Michael Josef
T1  - Label-free electrical detection of DNA by means of field-effect nanoplate capacitors: Experiments and modeling
JF  - Physica Status Solidi (a)
N2  - Label-free electrical detection of consecutive deoxyribonucleic acid (DNA) hybridization/denaturation by means of an array of individually addressable field-effect-based nanoplate silicon-on-insulator (SOI) capacitors modified with gold nanoparticles (Au-NP) is investigated. The proposed device detects charge changes on Au-NP/DNA hybrids induced by the hybridization or denaturation event. DNA hybridization was performed in a high ionic-strength solution to provide a high hybridization efficiency. On the other hand, to reduce the screening of the DNA charge by counter ions and to achieve a high sensitivity, the sensor signal induced by the hybridization and denaturation events was measured in a low ionic-strength solution. High sensor signals of about 120, 90, and 80 mV were registered after the DNA hybridization, denaturation, and re-hybridization events, respectively. Fluorescence microscopy has been applied as reference method to verify the DNA immobilization, hybridization, and denaturation processes. An electrostatic charge-plane model for potential changes at the gate surface of a nanoplate field-effect sensor induced by the DNA hybridization has been developed taking into account both the Debye length and the distance of the DNA charge from the gate surface.
Y1  - 2012
U6  - https://doi.org/10.1002/pssa.201100710
SN  - 1862-6319
VL  - 209
SP  - 925
EP  - 934
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Poghossian, Arshak
A1  - Geissler, Hanno
A1  - Schöning, Michael Josef
T1  - Rapid methods and sensors for milk quality monitoring and spoilage detection
JF  - Biosensors and Bioelectronics
Y1  - 2019
U6  - https://doi.org/10.1016/j.bios.2019.04.040
SN  - 0956-5663
VL  - 140
IS  - Article 111272
PB  - Elsevier
CY  - Amsterdam
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  - Procedia Chemistry. 1 (2009), H. 1
Y1  - 2009
SN  - 1876-6196
N1  - Proceedings of the Eurosensors XXIII conference ; Eurosensors 23
SP  - 835
EP  - 838
ER  -