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  - http://dx.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  - 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  - http://dx.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  - Guo, Yuanyuan
A1  - Seki, Kosuke
A1  - Miyamoto, Ko-ichiro
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
A1  - Yoshinobu, Tatsuo
T1  - Device simulation of the light-addressable potentiometric sensor with a novel photoexcitation method for a higher spatial resolution
JF  - Procedia Engineering
N2  - A novel photoexcitation method for the light-addressable potentiometric sensor (LAPS) realized a higher spatial resolution of chemical imaging. In this method, a modulated light probe, which generates the alternating photocurrent signal, is surrounded by a ring of constant light, which suppresses the lateral diffusion of photocarriers by enhancing recombination. A device simulation verified that a higher spatial resolution could be obtained by adjusting the gap between the modulated and constant light. It was also found that a higher intensity and a longer wavelength of constant light was more effective. However, there exists a tradeoff between the spatial resolution and the amplitude of the photocurrent, and thus, the signal-to-noise ratio. A tilted incidence of constant light was applied, which could achieve even higher resolution with a smaller loss of photocurrent.
KW  - Light-addressable Potentiometric Sensor
KW  - novel photoexcitation method
KW  - tilted constant illumination
KW  - spatial resolution
Y1  - 2014
U6  - http://dx.doi.org/10.1016/j.proeng.2014.11.369
SN  - 1877-7058
N1  - EUROSENSORS 2014 ; European Conference on Solid-State Transducers <28, 2014>
VL  - 87
SP  - 456
EP  - 459
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Miyamoto, K.
A1  - Seki, K.
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
A1  - Yoshinobu, T.
T1  - Enhancement of the spatial resolution of the chemical imaging sensor by a hybrid fiber-optic illumination
JF  - Procedia Engineering
N2  - The chemical imaging sensor, which is based on the principle of the light-addressable potentiometric sensor (LAPS), is a powerful tool to visualize the spatial distribution of chemical species on the sensor surface. The spatial resolution of this sensor depends on the diffusion of photocarriers excited by a modulated light. In this study, a novel hybrid fiber-optic illumination was developed to enhance the spatial resolution. It consists of a modulated light probe to generate a photocurrent signal and a ring of constant light, which suppresses the lateral diffusion of minority carriers excited by the modulated light. It is demonstrated that the spatial resolution was improved from 92 μm to 68 μm.
Y1  - 2014
U6  - http://dx.doi.org/10.1016/j.proeng.2014.11.563
SN  - 1877-7058
N1  - EUROSENSORS 2014 ; European Conference on Solid-State Transducers <28, 2014>
VL  - 87
SP  - 612
EP  - 615
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Bronder, Thomas
A1  - Wu, Chunsheng
A1  - Poghossian, Arshak
A1  - Werner, Frederik
A1  - Keusgen, M.
A1  - Schöning, Michael Josef
T1  - Label-free detection of DNA hybridization with light-addressable potentiometric sensors: comparison of various DNA-immobilization strategies
JF  - Procedia Engineering
N2  - Light-addressable potentiometric sensors (LAPS) consisting of a p-Si-SiO2 and p-Si-SiO2-Au structure, respectively, have been tested for a label-free electrical detection of DNA (deoxyribonucleic acid) hybridization. Three different strategies for immobilizing single-stranded probe DNA (ssDNA) molecules on a LAPS surface have been studied and compared: (a) immobilization of thiol-modified ssDNA on the patterned Au surface via gold-thiol bond, (b) covalent immobilization of amino-modified ssDNA onto the SiO2 surface functionalized with 3-aminopropyltriethoxysilane and (c) layer-by-layer adsorption of negatively charged ssDNA on a positively charged weak polyelectrolyte layer of poly(allylamine hydrochloride).
KW  - LAPS
KW  - lable-free detection
KW  - DNA hybridization
KW  - field-effect sensor
Y1  - 2014
U6  - http://dx.doi.org/10.1016/j.proeng.2014.11.647
SN  - 1877-7058
N1  - EUROSENSORS 2014 ; European Conference on Solid-State Transducers <28, 2014>
VL  - 87
SP  - 755
EP  - 758
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Huck, Christina
A1  - Poghossian, Arshak
A1  - Bäcker, Matthias
A1  - Reisert, Steffen
A1  - Schubert, J.
A1  - Zander, W.
A1  - Begoyan, V. K.
A1  - Buniatyan, V. V.
A1  - Schöning, Michael Josef
T1  - Chemical sensors based on a high-k perovskite oxide of barium strontium titanate
JF  - Procedia Engineering
N2  - High-k perovskite oxide of barium strontium titanate (BST) represents a very attractive multi-functional transducer material for the development of (bio-)chemical sensors for liquids. In this work, BST films have been applied as a sensitive transducer material for a label-free detection of adsorbed charged macromolecules (positively charged polyelectrolytes) and concentration of hydrogen peroxide vapor as well as protection insulator layer for a contactless electrolyte-conductivity sensor. The experimental results of characterization of individual sensors are presented. Special emphasis is devoted towards the development of a capacitively-coupled contactless electrolyte-conductivity sensor.
KW  - barium strontium titanate
KW  - high-k material
KW  - contactless conductivity sensor
KW  - multi-functional material
KW  - hydrogen peroxide
Y1  - 2014
U6  - http://dx.doi.org/10.1016/j.proeng.2014.11.258
SN  - 1877-7058
N1  - EUROSENSORS 2014 ; European Conference on Solid-State Transducers <28, 2014>
VL  - 87
SP  - 28
EP  - 31
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Schusser, Sebastian
A1  - Bäcker, Matthias
A1  - Krischer, M.
A1  - Wenzel, L.
A1  - Leinhos, Marcel
A1  - Poghossian, Arshak
A1  - Biselli, Manfred
A1  - Wagner, P.
A1  - Schöning, Michael Josef
T1  - Enzymatically catalyzed degradation of biodegradable polymers investigated by means of a semiconductor-based field-effect sensor
JF  - Procedia Engineering
N2  - A semiconductor field-effect device has been used for an enzymatically catalyzed degradation of biopolymers for the first time. This novel technique is capable to monitor the degradation process of multiple samples in situ and in real-time. As model system, the degradation of the biopolymer poly(D, L-lactic acid) has been monitored in the degradation medium containing the enzyme lipase from Rhizomucor miehei. The obtained results demonstrate the potential of capacitive field-effect sensors for degradation studies of biodegradable polymers.
KW  - Field-effect sensor
KW  - enzymatic (bio)degradation
KW  - poly(d, l-lactic acid)
KW  - in-situ monitoring
KW  - impedance spectroscopy
Y1  - 2014
U6  - http://dx.doi.org/10.1016/j.proeng.2014.11.689
SN  - 1877-7058
N1  - EUROSENSORS 2014 ; European Conference on Solid-State Transducers <28, 2014>
VL  - 87
SP  - 1314
EP  - 1317
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Murib, M. S.
A1  - Yeap, W. S.
A1  - Martens, D.
A1  - Liu, X.
A1  - Bienstman, P.
A1  - Fahlman, M.
A1  - Schöning, Michael Josef
A1  - Michiels, L.
A1  - Haenen, K.
A1  - Serpengüzel, A.
A1  - Wagner, Patrick
T1  - Photonic studies on polymer-coated sapphire-spheres : a model system for biological ligands
JF  - Sensors and actuators A: Physical
N2  - In this study we show an optical biosensor concept, based on elastic light scattering from sapphire microspheres. Transmitted and elastic scattering intensity of the microspheres (radius 500 μm, refractive index 1.77) on an optical fiber half coupler is analyzed at 1510 nm. The 0.43 nm angular mode spacing of the resonances is comparable to the angular mode spacing value estimated using the optical size of the microsphere. The spectral linewidths of the resonances are in the order of 0.01 nm, which corresponds to quality factors of approximately 105. A polydopamine layer is used as a functionalizing agent on sapphire microspherical resonators in view of biosensor implementation. The varying layer thickness on the microsphere is determined as a function of the resonance wavelength shift. It is shown that polymer functionalization has a minor effect on the quality factor. This is a promising step toward the development of an optical biosensor.
Y1  - 2015
U6  - http://dx.doi.org/10.1016/j.sna.2014.11.024
SN  - 1873-3069 (E-Journal); 0924-4247 (Print)
VL  - 222
SP  - 212
EP  - 219
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Schütz, S.
A1  - Weißbecker, B.
A1  - Hummel, Hans E.
A1  - Schöning, Michael Josef
A1  - Riemer, A.
A1  - Kordos, P.
A1  - Lüth, H.
T1  - Field effect transistor-insect antenna junction
JF  - Naturwissenschaften
Y1  - 1997
SN  - 1432-1904
VL  - 84
SP  - 86
EP  - 88
ER  - 
TY  - JOUR
A1  - Thust, Marion
A1  - Schöning, Michael Josef
A1  - Frohnhoff, S.
A1  - Arens-Fischer, R.
A1  - Kordos, P.
A1  - Lüth, H.
T1  - Porous silicon as a substrate material for potentiometric biosensors
JF  - Measurement Science and Technology
Y1  - 1996
U6  - http://dx.doi.org/10.1088/0957-0233/7/1/003
VL  - 7
IS  - 1
SP  - 26
EP  - 29
ER  - 
TY  - JOUR
A1  - Schöning, Michael Josef
A1  - Bäcker, Matthias
T1  - Chip-basierte Sensoren für die Biotechnik
Y1  - 2012
SN  - 1611-0854
N1  - 4 Seiten
VL  - 13
IS  - 2
PB  - BIOCOM
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Miyamoto, K.
A1  - Werner, Frederik
A1  - Schöning, Michael Josef
A1  - Yoshinobu, T.
T1  - Utilising Digital Micro-Mirror Device (DMD) as Scanning Light Source for Light-Addressable Potentiometric Sensors (LAPS)
Y1  - 2011
U6  - http://dx.doi.org/10.1166/sl.2011.1620
VL  - 9
IS  - 2
SP  - 812
EP  - 815
PB  - American Scientific Publishers
CY  - Stevenson Ranch, Calif.
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  - http://dx.doi.org/10.1002/elan.200603609
SN  - 1521-4109
VL  - 18
IS  - 19-20
SP  - 1893
EP  - 1900
ER  - 
TY  - JOUR
A1  - Spelthahn, Heiko
A1  - Schubert, Jürgen
A1  - Schöning, Michael Josef
T1  - Dünnschichtsensoren für die Schwermetallanalytik : Mikroelektroden auf Chalkogenidglasbasis
JF  - GIT Labor-Fachzeitschrift
N2  - Die Detektion von Schadstoffen repräsentiert in der Umweltanalytik eine wichtige Aufgabenstellung. Gerade die Abwasser- bzw. Brauchwasseranalytik sowie die Prozesskontrolle haben einen hohen Stellenwert. Siliziumbasierte Dünnschichtsensoren bieten eine kostengünstige Möglichkeit, „online“-Messungen bzw. Vor-Ort-Messungen zeitnah durchzuführen. In dieser Arbeit wird ein potentiometrisches Sensorarray auf der Basis von Chalkogenidgläsern zur Detektion von Schwermetallen in wässrigen Medien vorgestellt.
Y1  - 2012
IS  - 4
SP  - 285
EP  - 287
PB  - Wiley-VCH
CY  - Weinheim
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  - http://dx.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  - Leinhos, Marcel
A1  - Jablonski, Melanie
A1  - Poghossian, Arshak
A1  - Schöning, Michael Josef
T1  - Studying the spatially resolved immobilisation of enzymes on a capacitive field-effect structure by means of nano-spotting
JF  - Physica status solidi (a)
Y1  - 2015
U6  - http://dx.doi.org/10.1002/pssa.201431891
SN  - 1862-6319
VL  - 212
IS  - 6
SP  - 1353
EP  - 1358
PB  - Wiley
CY  - Weinheim
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  - http://dx.doi.org/10.1039/C5CC01362C
VL  - 51
SP  - 6564
EP  - 6567
PB  - Royal Society of Chemistry (RSC)
CY  - Cambridge
ER  - 
TY  - JOUR
A1  - Oberländer, Jan
A1  - Bromm, Alexander
A1  - Wendeler, Luisa
A1  - Iken, Heiko
A1  - Palomar Duran, Marlena
A1  - Greeff, Anton
A1  - Kirchner, Patrick
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Towards a biosensor to monitor the sterilisation efficiency of aseptic filling machines
JF  - Physica status solidi (a)
N2  - Sterilisation processes are compulsory in medicine, pharmacy, and food industries to prevent infections of consumers and microbiological contaminations of products. Monitoring the sterilisation by conventional microbiological methods is time- and lab-consuming. To overcome this problem, in this work a novel biosensor has been proposed. The sensor enables a fast method to evaluate sterilisation processes. By means of thin-film technology the sensor's transducer structures in form of IDEs (interdigitated electrodes) have been fabricated on a silicon substrate. Physical characterisation of the developed sensor was done by AFM, SEM, and profilometry. Impedance analyses were conducted for the electrical characterisation. As microbiological layer spores of B. atrophaeus have been immobilised on the sensing structure; spores of this type are a well-known sterilisation test organism. Impedance measurements at a fixed frequency over time were performed to monitor the immobilisation process. A sterilisation process according to aseptic filling machines was applied to demonstrate the sensor functionality. After both, immobilisation and sterilisation, a change in impedance could successfully be detected.
Y1  - 2015
U6  - http://dx.doi.org/10.1002/pssa.201431900
SN  - 1862-6319
VL  - 212
IS  - 6
SP  - 1299
EP  - 1305
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Huck, Christina
A1  - Poghossian, Arshak
A1  - Bäcker, Matthias
A1  - Reisert, Steffen
A1  - Kramer, Friederike
A1  - Begoyan, Vardges K.
A1  - Buniatyan, Vahe V.
A1  - Schöning, Michael Josef
T1  - Multi-parameter sensing using high-k oxide of barium strontium titanate
JF  - Physica status solidi (a)
N2  - High-k perovskite oxide of barium strontium titanate (BST) represents a very attractive multi-functional transducer material for the development of (bio-)chemical sensors. In this work, a Si-based sensor chip containing Pt interdigitated electrodes covered with a thin BST layer (485 nm) has been developed for multi-parameter chemical sensing. The chip has been applied for the contactless measurement of the electrolyte conductivity, the detection of adsorbed charged macromolecules (positively charged polyelectrolytes of polyethylenimine) and the concentration of hydrogen peroxide (H2O2) vapor. The experimental results of functional testing of individual sensors are presented. The mechanism of the BST sensitivity to charged polyelectrolytes and H2O2 vapor has been proposed and discussed.
Y1  - 2015
U6  - http://dx.doi.org/10.1002/pssa.201431911
SN  - 1862-6319
VL  - 212
IS  - 6
SP  - 1259
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Jildeh, Zaid B.
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
A1  - Pieper, Martin
T1  - Simulating the electromagnetic‐thermal treatment of thin aluminium layers for adhesion improvement
JF  - Physica status solidi (a)
N2  - A composite layer material used in packaging industry is made from joining layers of different materials using an adhesive. An important processing step in the production of aluminium-containing composites is the surface treatment and consequent coating of adhesive material on the aluminium surface. To increase adhesion strength between aluminium layer and the adhesive material, the foil is heat treated. For efficient heating, induction heating was considered as state-of-the-art treatment process. Due to the complexity of the heating process and the unpredictable nature of the heating source, the control of the process is not yet optimised. In this work, a finite element analysis of the process was established and various process parameters were studied. The process was simplified and modelled in 3D. The numerical model contains an air domain, an aluminium layer and a copper coil fitted with a magnetic field concentrating material. The effect of changing the speed of the aluminium foil (or rolling speed) was studied with the change of the coil current. Statistical analysis was used for generating a general control equation of coil current with changing rolling speed.
Y1  - 2015
U6  - http://dx.doi.org/10.1002/pssa.201431893
SN  - 1862-6319
VL  - Vol. 212
IS  - 6
SP  - 1234
EP  - 1241
PB  - Wiley
CY  - Weinheim
ER  -