TY  - JOUR
A1  - Janus, Kevin Alexander
A1  - Achtsnicht, Stefan
A1  - Tempel, Laura
A1  - Drinic, Aleksaner
A1  - Kopp, Alexander
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Influence of fibroin membrane composition and curing parameters on the performance of a biodegradable enzymatic biosensor manufactured from Silicon-Free Carbon
JF  - Physica status solidi : pss. A, Applications and materials science
N2  - Herein, fibroin, polylactide (PLA), and carbon are investigated for their suitability as biocompatible and biodegradable materials for amperometric biosensors. For this purpose, screen-printed carbon electrodes on the biodegradable substrates fibroin and PLA are modified with a glucose oxidase membrane and then encapsulated with the biocompatible material Ecoflex. The influence of different curing parameters of the carbon electrodes on the resulting biosensor characteristics is studied. The morphology of the electrodes is investigated by scanning electron microscopy, and the biosensor performance is examined by amperometric measurements of glucose (0.5–10 mM) in phosphate buffer solution, pH 7.4, at an applied potential of 1.2 V versus a Ag/AgCl reference electrode. Instead of Ecoflex, fibroin, PLA, and wound adhesive are tested as alternative encapsulation compounds: a series of swelling tests with different fibroin compositions, PLA, and Ecoflex has been performed before characterizing the most promising candidates by chronoamperometry. Therefore, the carbon electrodes are completely covered with the particular encapsulation material. Chronoamperometric measurements with H2O2 concentrations between 0.5 and 10 mM enable studying the leakage current behavior.
KW  - amperometric biosensors
KW  - biocompatible
KW  - biodegradabl
KW  - encapsulation materials
KW  - fibroin
Y1  - 2023
U6  - http://dx.doi.org/10.1002/pssa.202300081
SN  - 1862-6300 (Print)
SN  - 1862-6319 (Online)
N1  - Corresponding author: Michael J. Schöning
VL  - 220
IS  - 22
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Siqueira, Jose R.
A1  - Molinnus, Denise
A1  - Beging, Stefan
A1  - Schöning, Michael Josef
T1  - Incorporating a hybrid urease-carbon nanotubes sensitive nanofilm on capacitive field-effect sensors for urea detection
JF  - Analytical chemistry
N2  - The ideal combination among biomolecules and nanomaterials is the key for reaching biosensing units with high sensitivity. The challenge, however, is to find out a stable and sensitive film architecture that can be incorporated on the sensor’s surface. In this paper, we report on the benefits of incorporating a layer-by-layer (LbL) nanofilm of polyamidoamine (PAMAM) dendrimer and carbon nanotubes (CNTs) on capacitive electrolyte-insulator-semiconductor (EIS) field-effect sensors for detecting urea. Three sensor arrangements were studied in order to investigate the adequate film architecture, involving the LbL film with the enzyme urease: (i) urease immobilized directly onto a bare EIS [EIS-urease] sensor; (ii) urease atop the LbL film over the EIS [EIS-(PAMAM/CNT)-urease] sensor; and (iii) urease sandwiched between the LbL film and another CNT layer [EIS-(PAMAM/CNT)-urease-CNT]. The surface morphology of all three urea-based EIS biosensors was investigated by atomic force microscopy (AFM), while the biosensing abilities were studied by means of capacitance–voltage (C/V) and dynamic constant-capacitance (ConCap) measureaments at urea concentrations ranging from 0.1 mM to 100 mM. The EIS-urease and EIS-(PAMAM/CNT)-urease sensors showed similar sensitivity (∼18 mV/decade) and a nonregular signal behavior as the urea concentration increased. On the other hand, the EIS-(PAMAM/CNT)-urease-CNT sensor exhibited a superior output signal performance and higher sensitivity of about 33 mV/decade. The presence of the additional CNT layer was decisive to achieve a urea based EIS sensor with enhanced properties. Such sensitive architecture demonstrates that the incorporation of an adequate hybrid enzyme-nanofilm as sensing unit opens new prospects for biosensing applications using the field-effect sensor platform.
Y1  - 2014
U6  - http://dx.doi.org/10.1021/ac500458s
SN  - 1520-6882 (E-Journal); 0003-2700 (Print); 0096-4484 (Print)
VL  - 86
IS  - 11
SP  - 5370
EP  - 5375
PB  - ACS Publications
CY  - Columbus
ER  - 
TY  - JOUR
A1  - Thust, M.
A1  - Schroth, P.
A1  - Töpler, A.
A1  - Schöning, Michael Josef
A1  - Müller-Veggian, Mattea
A1  - Kordos, P.
A1  - Lüth, H.
T1  - Improving the detection limit of a capacitive sensor by means of a diffusion barrier
JF  - Eurosensors XII : proceedings of the 12th European Conference on Solid-State Transducers and the 9th UK Conference on Sensors and their Applications, Southampton, UK, 13 - 16 September 1998 / ed. by N. M. White ; Vol. 1
Y1  - 1998
SN  - 0-7503-0595-9
N1  - Eurosensors ; (12, 1998, Southampton) ; UK Conference on Sensors and Their Applications ; (9, 1998, Southampton)
SP  - 507
EP  - 510
PB  - Inst. of Physics Publ.
CY  - Bristol [u.a.]
ER  - 
TY  - JOUR
A1  - Schroth, P.
A1  - Schöning, Michael Josef
A1  - Schütz, S.
A1  - Epanya, P.
A1  - Steffen, A.
A1  - Weißbecker, B.
A1  - Hummel, Hans E.
A1  - Kordos, P.
A1  - Lüth, H.
T1  - Improving the bioelectronic interface of an antenna/chip biosensor – technological aspects
JF  - Proceedings : The Hague, The Netherlands, September 12 - 15, 1999 / [ed. by M. Bartek]. Vol 1.
Y1  - 1999
SN  - 90-76699-02-X
N1  - Eurosensors ; (13, 1999, 's-Gravenhage) ; Eurosensors ; (13 : ; 1999.09.12-15 : ; The Hague) ; European Conference on Solid-State Transducers ; (13 : ; 1999.09.12-15 : ; The Hague)
SP  - 569
EP  - 572
CY  - The Hague, The Netherlands
ER  - 
TY  - JOUR
A1  - Miyamoto, Koichiro
A1  - Seki, Kosuke
A1  - Suto, Takeyuki
A1  - Werner, Frederik
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
A1  - Yoshinobu, Tatsuo
T1  - Improved spatial resolution of the chemical imaging sensor with a hybrid illumination that suppresses lateral diffusion of photocarriers
JF  - Sensor and Actuators B: Chemical
N2  - The chemical imaging sensor is a semiconductor-based chemical sensor capable of visualizing pH and ion distributions. The spatial resolution depends on the lateral diffusion of photocarriers generated by illumination of the semiconductor substrate. In this study, two types of optical setups, one based on a bundle of optical fibers and the other based on a binocular tube head, were developed to project a hybrid illumination of a modulated light beam and a ring-shaped constant illumination onto the sensor plate. An improved spatial resolution was realized by the ring-shaped constant illumination, which suppressed lateral diffusion of photocarriers by enhanced recombination due to the increased carrier concentration.
Y1  - 2018
U6  - http://dx.doi.org/10.1016/j.snb.2018.07.016
SN  - 0925-4005
VL  - 273
SP  - 1328
EP  - 1333
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Delle, Lotta E.
A1  - Huck, Christina
A1  - Bäcker, Matthias
A1  - Müller, Frank
A1  - Grandthyll, Samuel
A1  - Jacobs, Karin
A1  - Lilischkis, Rainer
A1  - Vu, Xuan T.
A1  - Schöning, Michael Josef
A1  - Wagner, Patrick
A1  - Thoelen, Roland
A1  - Weil, Maryam
A1  - Ingebrandt, Sven
T1  - Impedimetric immunosensor for the detection of histamine based on reduced graphene oxide
JF  - Physica status solidi (a)
Y1  - 2015
U6  - http://dx.doi.org/10.1002/pssa.201431863
SN  - 1862-6319
VL  - 212
IS  - 6
SP  - 1327
EP  - 1334
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Riedel, Marc
A1  - Kartchemnik, Julia
A1  - Schöning, Michael Josef
A1  - Lisdat, Fred
T1  - Impedimetric DNA detection – steps forward to sensorial application
JF  - Analytical chemistry
N2  - This study describes a label-free impedimetric sensor based on short ssDNA recognition elements for the detection of hybridization events. We concentrate on the elucidation of the influence of target length and recognition sequence position on the sensorial performance. The impedimetric measurements are performed in the presence of the redox system ferri-/ferrocyanide and show an increase in charge transfer resistance upon hybridization of ssDNA to the sensor surface. Investigations on the impedimetric signal stability demonstrate a clear influence of the buffers used during the sensor preparation and the choice of the passivating mercaptoalcanol compound. A stable sensor system has been developed, enabling a reproducible detection of 25mer target DNA in the low nanomolar range. After hybridization, a sensor regeneration can be reached with deionized water by adjustment of effective convection conditions, ensuring a sensor reusability. By investigations of longer targets with overhangs exposed to the solution, we can demonstrate applicability of the impedimetric detection for longer ssDNA. However, a decreasing charge transfer resistance change (ΔRct) is found by extending the overhang. As a strategy to increase the impedance change for longer target strands, the position of the recognition sequence can be designed in a way that a small overhang is exposed to the electrode surface. This is found to result in an increase in the relative Rct change. These results suggest that DNA and consequently negative charge near the electrode possess a larger impact on the impedimetric signal than DNA further away.
Y1  - 2014
U6  - http://dx.doi.org/10.1021/ac501800q
SN  - 1520-6882 (E-Journal); 0003-2700 (Print); 0096-4484 (Print)
VL  - 86 (2014)
IS  - 15
SP  - 7867
EP  - 7874
PB  - ACS Publications
CY  - Columbus
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  - http://dx.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  - JOUR
A1  - Poghossian, Arshak
A1  - Mai, D.-T.
A1  - Mourzina, Y.
A1  - Schöning, Michael Josef
T1  - Impedance effect of an ion-sensitive membrane: characterisation of an EMIS sensor by impedance spectroscopy, capacitance-voltage and constant-capacitance method
JF  - Sensors and Actuators B. 103 (2004), H. 1-2
Y1  - 2004
SN  - 0925-4005
SP  - 423
EP  - 428
ER  - 
TY  - JOUR
A1  - Mourzina, Ioulia G.
A1  - Yoshinobu, Tatsuo
A1  - Ermolenko, Yuri E.
A1  - Vlasov, Yuri G.
A1  - Schöning, Michael Josef
A1  - Iwasaki, H.
T1  - Immobilization of urease and cholinesterase on the surface of semiconductor transducer for the development of lightaddressable potentiometric sensors
JF  - Microchimica Acta. 144 (2004), H. 1-3
Y1  - 2004
SN  - 0026-3672
SP  - 41
EP  - 50
ER  - 
TY  - JOUR
A1  - Mourzina, I.G.
A1  - Yoshinobu, T.
A1  - Ermolenko, Y.E.
A1  - Vlasov, Y. G.
A1  - Schöning, Michael Josef
A1  - Iwasaki, H.
T1  - Immobilization of urease and cholinesterase on the surface of semiconductor transducer for the development of light-addressable potentiometric sensors
JF  - Technical digest of the 10th International Meeting on Chemical Sensors, July 11 - 14, 2004, Tsukuba, Japan / Japan Association of Chemical Sensors
Y1  - 2004
N1  - Chemical sensors ; 20.2004 Suppl. B. IMCS ; (10, 2004, Tsukuba) ; International Meeting on Chemical Sensors ; (10 : ; 2004.07.11-14 : ; Tsukuba)
SP  - 788
EP  - 789
PB  - Japan Association of Chemical Sensors
CY  - Fukuoka
ER  - 
TY  - JOUR
A1  - Miyamoto, Ko-ichiro
A1  - Sugawara, Yuri
A1  - Kanoh, Shin´ichiro
A1  - Yoshinobu, Tatsuo
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
T1  - Image correction method for the chemical imaging sensor
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  - 344
EP  - 348
ER  - 
TY  - JOUR
A1  - Breuer, Lars
A1  - Raue, Markus
A1  - Strobel, M.
A1  - Mang, Thomas
A1  - Schöning, Michael Josef
A1  - Thoelen, R.
A1  - Wagner, Torsten
T1  - Hydrogels with incorporated graphene oxide as light-addressable actuator materials for cell culture environments in lab-on-chip systems
JF  - Physica status solidi (a)
N2  - Abstractauthoren Graphene oxide (GO) nanoparticles were incorporated in temperature-sensitive Poly(N-isopropylacrylamide) (PNIPAAm) hydrogels. The nanoparticles increase the light absorption and convert light energy into heat efficiently. Thus, the hydrogels with GO can be stimulated spatially resolved by illumination as it was demonstrated by IR thermography. The temporal progression of the temperature maximum was detected for different concentrations of GO within the polymer network. Furthermore, the compatibility of PNIPAAm hydrogels with GO and cell cultures was investigated. For this purpose, culture medium was incubated with hydrogels containing GO and the viability and morphology of chinese hamster ovary (CHO) cells was examined after several days of culturing in presence of this medium.
Y1  - 2016
U6  - http://dx.doi.org/10.1002/pssa.201533056
SN  - 1862-6300
VL  - 213
IS  - 6
SP  - 1520
EP  - 1525
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Morais, Paulo V.
A1  - Silva, Anielle C. A.
A1  - Dantas, Noelio O.
A1  - Schöning, Michael Josef
A1  - Siqueira, José R., Jr.
T1  - Hybrid Layer‐by‐Layer Film of Polyelectrolytes‐Embedded Catalytic CoFe2O4 Nanocrystals as Sensing Units in Capacitive Electrolyte‐Insulator‐Semiconductor Devices
JF  - physica status solidi a : applications and materials sciences
Y1  - 2019
U6  - http://dx.doi.org/10.1002/pssa.201900044
VL  - 216
IS  - 1900044
SP  - 1
EP  - 9
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Itabashi, Akinori
A1  - Kosaka, Naoki
A1  - Miyamoto, Ko-ichiro
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
T1  - High-speed chemical imaging system based on front-side-illuminated LAPS
JF  - Sensors and actuators B: Chemical
N2  - The chemical imaging sensor is a semiconductor-based chemical sensor that can visualize the spatial distribution of specific ions on the sensing surface. The conventional chemical imaging system based on the light-addressable potentiometric sensor (LAPS), however, required a long time to obtain a chemical image, due to the slow mechanical scan of a single light beam. For high-speed imaging, a plurality of light beams modulated at different frequencies can be employed to measure the ion concentrations simultaneously at different locations on the sensor plate by frequency division multiplex (FDM). However, the conventional measurement geometry of back-side illumination limited the bandwidth of the modulation frequency required for FDM measurement, because of the low-pass filtering characteristics of carrier diffusion in the Si substrate. In this study, a high-speed chemical imaging system based on front-side-illuminated LAPS was developed, which achieved high-speed spatiotemporal recording of pH change at a rate of 70 frames per second.
Y1  - 2013
U6  - http://dx.doi.org/10.1016/j.snb.2013.03.016
SN  - 1873-3077
VL  - 182
SP  - 315
EP  - 321
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Miyamoto, Ko-ichiro
A1  - Itabashi, Akinori
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
A1  - Yoshinobu, Tatsuo
T1  - High-speed chemical imaging inside a microfluidic channel
JF  - Sensors and actuators. B: Chemical
N2  - In this study, a high-speed chemical imaging system was developed for visualization of the interior of a microfluidic channel. A microfluidic channel was constructed on the sensor surface of the light-addressable potentiometric sensor (LAPS), on which the ion concentrations could be measured in parallel at up to 64 points illuminated by optical fibers. The temporal change of pH distribution inside the microfluidic channel was recorded at a maximum rate of 100 frames per second (fps). The high frame rate allowed visualization of moving interfaces and plugs in the channel even at a flow velocity of 111 mm/s, which suggests the feasibility of plug-based microfluidic devices for flow-injection analysis (FIA).
Y1  - 2014
U6  - http://dx.doi.org/10.1016/j.snb.2013.12.090
SN  - 1873-3077 (E-Journal); 0925-4005 (Print)
VL  - 194
SP  - 521
EP  - 527
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Werner, Frederik
A1  - Wagner, Torsten
A1  - Miyamoto, Ko-ichiro
A1  - Yoshinobu, Tatsuo
A1  - Schöning, Michael Josef
T1  - High speed and high resolution chemical imaging based on a new type of OLED-LAPS set-up
JF  - Sensors and Actuators B: Chemical
N2  - Light-addressable potentiometric sensors (LAPS) are field-effect-based sensors. A modulated light source is used to define the particular measurement spot to perform spatially resolved measurements of chemical species and to generate chemical images. In this work, an organic-LED (OLED) display has been chosen as a light source. This allows high measurement resolution and miniaturisation of the system. A new developed driving method for the OLED display optimised for LAPS-based measurements is demonstrated. The new method enables to define modulation frequencies between 1 kHz and 16 kHz and hence, reduces the measurement time of a chemical image by a factor of 40 compared to the traditional addressing of an OLED display.
Y1  - 2012
U6  - http://dx.doi.org/10.1016/j.snb.2011.12.102
SN  - 0925-4005
N1  - Part of special issue "Selected Papers presented at Eurosensors XXV"
VL  - 175
SP  - 118
EP  - 122
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Werner, Frederik
A1  - Wagner, Torsten
A1  - Miyamoto, Ko-ichiro
A1  - Yoshinobu, Tatsuo
A1  - Schöning, Michael Josef
T1  - High speed and high resolution chemical imaging based on a new type of OLED-LAPS set-up
JF  - Procedia Engineering. 25 (2011)
Y1  - 2011
SN  - 1877-7058
N1  - EurosensorsXXV ; Proc. Eurosensors XXV, September 4-7, 2011, Athens, Greece
SP  - 346
EP  - 349
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Moritz, W.
A1  - Yoshinobu, T.
A1  - Finger, F.
A1  - Krause, S.
A1  - Martin-Fernandez, M.
A1  - Schöning, Michael Josef
T1  - High resolution LAPS using amorphous silicon as the semiconductor material
JF  - Sensors and Actuators B. 103 (2004), H. 1-2
Y1  - 2004
SN  - 0925-4005
SP  - 436
EP  - 444
ER  - 
TY  - JOUR
A1  - Bressel, A.
A1  - Schultze, J.W.
A1  - Khan, W.
A1  - Wolfaardt, G. M.
A1  - Rohns, H.-P.
A1  - Irmscher, R.
A1  - Schöning, Michael Josef
T1  - High resolution gravimetric, optical and electrochemical investigations of microbial biofilm formation in aqueous systems
JF  - Electrochimica Acta. 48 (2003), H. 20-22
Y1  - 2003
SN  - 0013-4686
SP  - 3363
EP  - 3372
ER  -