TY  - JOUR
A1  - Siqueira, Jose R.
A1  - Werner, Frederik
A1  - Bäcker, Matthias
A1  - Poghossian, Arshak
A1  - Zucolotto, Valtencir
A1  - Oliveira, Osvaldo N. Jr.
A1  - Schöning, Michael Josef
T1  - Layer-by-Layer Assembly of Carbon Nanotubes Incorporated in Light-Addressable Potentiometric Sensors
JF  - Journal of Physical Chemistry C. 113 (2009), H. 33
Y1  - 2009
SN  - 1932-7455
SP  - 14765
EP  - 14770
PB  - American Chemical Society
CY  - Washington, DC
ER  - 
TY  - JOUR
A1  - Siqueira, José R. Jr.
A1  - Abouzar, Maryam H.
A1  - Bäcker, Matthias
A1  - Zucolotto, Valtencir
A1  - Poghossian, Arshak
A1  - Oliveira, Osvaldo N. Jr.
A1  - Schöning, Michael Josef
T1  - Carbon nanotubes in nanostructured films: Potential application as amperometric and potentiometric field-effect (bio-)chemical sensors
JF  - physica status solidi (a) . 206 (2009), H. 3
Y1  - 2009
SN  - 1862-6319
N1  - Special Issue: Engineering of Functional Interfaces (EnFI 08)
SP  - 462
EP  - 467
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Poghossian, Arshak
A1  - Abouzar, Maryam H.
A1  - Razavi, A.
A1  - Bäcker, Matthias
A1  - Bijnens, N.
A1  - Williams, O. A.
A1  - Haenen, K.
A1  - Moritz, W.
A1  - Wagner, P.
A1  - Schöning, Michael Josef
T1  - Nanocrystalline-diamond thin films with high pH and penicillin sensitivity prepared on a capacitive Si–SiO2 structure
JF  - Electrochimica Acta. 54 (2009), H. 25
Y1  - 2009
SN  - 0013-4686
SP  - 5981
EP  - 5985
ER  - 
TY  - JOUR
A1  - Bäcker, Matthias
A1  - Beging, Stefan
A1  - Biselli, Manfred
A1  - Poghossian, Arshak
A1  - Wang, J.
A1  - Zang, Werner
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Concept for a solid-state multi-parameter sensor system for cell-culture monitoring
JF  - Electrochimica Acta. 54 (2009), H. 25 Sp. Iss. SI
Y1  - 2009
SN  - 0013-4686
SP  - 6107
EP  - 6112
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Siqueira, José R. Jr.
A1  - Bäcker, Matthias
A1  - Poghossian, Arshak
A1  - Zucolotto, Valtencir
A1  - Oliveira, Osvaldo N. Jr.
A1  - Schöning, Michael Josef
T1  - Associating biosensing properties with the morphological structure of multilayers containing carbon nanotubes on field-effect devices
JF  - Physica status solidi (a). 207 (2010), H. 4
Y1  - 2010
SN  - 1862-6300
N1  - Special Issue: Engineering of Functional Interfaces EnFI 2009
SP  - 781
EP  - 786
ER  - 
TY  - JOUR
A1  - Bäcker, Matthias
A1  - Poghossian, Arshak
A1  - Abouzar, Maryam H.
A1  - Wenmackers, Sylvia
A1  - Janssens, Stoffel D.
A1  - Haenen, Ken
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Capacitive field-effect (bio-)chemical sensors based on nanocrystalline diamond films
JF  - Diamond Electronics and Bioelectronics — Fundamentals to Applications III, edited by P. Bergonzo, [u.a.]
Y1  - 2010
N1  - MRS Proceedings Volume 1203 paper 1203-J17-31 ; Mater. Res. Soc. Sympos. Proc. Vol 1203 (2010) ; Materials Research Society
SP  - 1
EP  - 6
ER  - 
TY  - JOUR
A1  - Bäcker, Matthias
A1  - Pouyeshman, S.
A1  - Schnitzler, Thomas
A1  - Poghossian, Arshak
A1  - Wagner, Patrick
A1  - Biselli, Manfred
A1  - Schöning, Michael Josef
T1  - A silicon-based multi-sensor chip for monitoring of fermentation processes
JF  - Physica status solidi (a) : applications and material science. 208 (2011), H. 6
Y1  - 2011
SN  - 1862-6319
SP  - 1364
EP  - 1369
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Bäcker, Matthias
A1  - Delle, L.
A1  - Poghossian, Arshak
A1  - Biselli, Manfred
A1  - Zang, Werner
A1  - Wagner, P.
A1  - Schöning, Michael Josef
T1  - Electrochemical sensor array for bioprocess monitoring
JF  - Electrochimica Acta (2011)
Y1  - 2011
VL  - 56
IS  - 26
SP  - 9673
EP  - 9678
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Bäcker, Matthias
A1  - Raue, Markus
A1  - Schusser, Sebastian
A1  - Jeitner, C.
A1  - Breuer, L.
A1  - Wagner, P.
A1  - Poghossian, Arshak
A1  - Förster, Arnold
A1  - Mang, Thomas
A1  - Schöning, Michael Josef
T1  - Microfluidic chip with integrated microvalves based on temperature- and pH-responsive hydrogel thin films
JF  - Physica Status Solidi  (a)
N2  - Two types of microvalves based on temperature-responsive poly(N-isopropylacrylamide) (PNIPAAm) and pH-responsive poly(sodium acrylate) (PSA) hydrogel films have been developed and tested. The PNIPAAm and PSA hydrogel films were prepared by means of in situ photopolymerization directly inside the fluidic channel of a microfluidic chip fabricated by combining Si and SU-8 technologies. The swelling/shrinking properties and height changes of the PNIPAAm and PSA films inside the fluidic channel were studied at temperatures of deionized water from 14 to 36 °C and different pH values (pH 3–12) of Titrisol buffer, respectively. Additionally, in separate experiments, the lower critical solution temperature (LCST) of the PNIPAAm hydrogel was investigated by means of a differential scanning calorimetry (DSC) and a surface plasmon resonance (SPR) method. Mass-flow measurements have shown the feasibility of the prepared hydrogel films to work as an on-chip integrated temperature- or pH-responsive microvalve capable to switch the flow channel on/off.
Y1  - 2012
U6  - http://dx.doi.org/10.1002/pssa.201100763
SN  - 1862-6319
VL  - 209
IS  - 5
SP  - 839
EP  - 845
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Schusser, Sebastian
A1  - Poghossian, Arshak
A1  - Bäcker, Matthias
A1  - Leinhos, Marcel
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Characterization of biodegradable polymers with capacitive field-effect sensors
JF  - Sensors and actuators B: Chemical
N2  - In vitro studies of the degradation kinetic of biopolymers are essential for the design and optimization of implantable biomedical devices. In the presented work, a field-effect capacitive sensor has been applied for the real-time and in situ monitoring of degradation processes of biopolymers for the first time. The polymer-covered field-effect sensor is, in principle, capable to detect any changes in bulk, surface and interface properties of the polymer induced by degradation processes. The feasibility of this approach has been experimentally proven by using the commercially available biomedical polymer poly(D,L-lactic acid) (PDLLA) as a model system. PDLLA films of different thicknesses were deposited on the Ta₂O₅-gate surface of the field-effect structure from a polymer solution by means of spin-coating method. The polymer-modified field-effect sensors have been characterized by means of capacitance–voltage and impedance-spectroscopy method. The degradation of the PDLLA was accelerated by changing the degradation medium from neutral (pH 7.2) to alkaline (pH 9) condition, resulting in drastic changes in the capacitance and impedance spectra of the polymer-modified field-effect sensor.
KW  - Impedance spectroscopy
KW  - C–V method
KW  - Real-time monitoring
KW  - Poly(d,l-lacticacid)
KW  - (Bio)degradation
KW  - Field-effect sensor
Y1  - 2012
U6  - http://dx.doi.org/10.1016/j.snb.2012.07.099
SN  - 0925-4005
N1  - Part of special issue "Selected Papers from the 14th International Meeting on Chemical Sensors"
VL  - 187
SP  - 2
EP  - 7
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Poghossian, Arshak
A1  - Weil, M. H.
A1  - Bäcker, Matthias
A1  - Mayer, D.
A1  - Schöning, Michael Josef
T1  - Field-effect Devices Functionalised with Gold-Nanoparticle/Macromolecule Hybrids: New Opportunities for a Label-Free Biosensing
JF  - Procedia Engineering
N2  - Field-effect capacitive electrolyte-insulator-semiconductor (EIS) sensors functionalised with citrate-capped gold nanoparticles (AuNP) have been used for the electrostatic detection of macromolecules by their intrinsic molecular charge. The EIS sensor detects the charge changes in the AuNP/macromolecule hybrids induced by the adsorption or binding events. A feasibility of the proposed detection scheme has been exemplary demonstrated by realising EIS sensors for the detection of poly-D-lysine molecules.
Y1  - 2012
U6  - http://dx.doi.org/10.1016/j.proeng.2012.09.136
SN  - 1877-7058
N1  - Part of special issue "26th European Conference on Solid-State Transducers, EUROSENSOR 2012"
IS  - 47
SP  - 273
EP  - 276
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - CHAP
A1  - Bohrn, Ulrich
A1  - Mucha, Andreas
A1  - Werner, Frederik
A1  - Stütz, Evamaria
A1  - Bäcker, Matthias
A1  - Krumbe, Christoph
A1  - Schienle, Meinrad
A1  - Fleischer, Maximilian
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Detection of toxic chromium species in water using cellbased sensor systems
Y1  - 2012
SN  - 978-3-9813484-2-2
U6  - http://dx.doi.org/10.5162/IMCS2012/P2.1.14
SP  - 1364
EP  - 1367
ER  - 
TY  - JOUR
A1  - Bohrn, Ulrich
A1  - Mucha, Andreas
A1  - Werner, Frederik
A1  - Trattner, Barbara
A1  - Bäcker, Matthias
A1  - Krumbe, Christoph
A1  - Schienle, Meinrad
A1  - Stütz, Evamaria
A1  - Schmitt-Landsiedel, Doris
A1  - Fleischer, Maximilian
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - A critical comparison of cell-based sensor systems for the detection of Cr (VI) in aquatic environment
JF  - Sensors and actuators. B: Chemical
Y1  - 2013
SN  - 1873-3077 (E-Journal); 0925-4005 (Print)
VL  - Vol. 182
SP  - 58
EP  - 65
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Schusser, Sebastian
A1  - Menzel, S.
A1  - Bäcker, Matthias
A1  - Leinhos, Marcel
A1  - Poghossian, Arshak
A1  - Wagner, P.
A1  - Schöning, Michael Josef
T1  - Degradation of thin poly(lactic acid) films: characterization by capacitance-voltage, atomic force microscopy, scanning electron microscopy and contact-angle measurements
JF  - Electrochimica Acta
Y1  - 2013
SN  - 1873-3859 (E-Journal); 0013-4686 (Print)
VL  - Vol. 113
SP  - 779
EP  - 784
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - CHAP
A1  - Wu, Chunsheng
A1  - Poghossian, Arshak
A1  - Werner, Frederik
A1  - Bronder, Thomas
A1  - Bäcker, Matthias
A1  - Wang, Ping
A1  - Schöning, Michael Josef
T1  - An application of a scanning light-addressable potentiometric sensor for label-free DNA detection
T2  - 11. Dresdner Sensor-Symposium : 9.-11.12.2013
Y1  - 2013
SN  - 978-3-9813484-5-3
SP  - 164
EP  - 168
ER  - 
TY  - JOUR
A1  - Bäcker, Matthias
A1  - Rakowski, D.
A1  - Poghossian, Arshak
A1  - Biselli, Manfred
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Chip-based amperometric enzyme sensor system for monitoring of bioprocesses by flow-injection analysis
JF  - Journal of Biotechnology
N2  - A microfluidic chip integrating amperometric enzyme sensors for the detection of glucose, glutamate and glutamine in cell-culture fermentation processes has been developed. The enzymes glucose oxidase, glutamate oxidase and glutaminase were immobilized by means of cross-linking with glutaraldehyde on platinum thin-film electrodes integrated within a microfluidic channel. The biosensor chip was coupled to a flow-injection analysis system for electrochemical characterization of the sensors. The sensors have been characterized in terms of sensitivity, linear working range and detection limit. The sensitivity evaluated from the respective peak areas was 1.47, 3.68 and 0.28 μAs/mM for the glucose, glutamate and glutamine sensor, respectively. The calibration curves were linear up to a concentration of 20 mM glucose and glutamine and up to 10 mM for glutamate. The lower detection limit amounted to be 0.05 mM for the glucose and glutamate sensor, respectively, and 0.1 mM for the glutamine sensor. Experiments in cell-culture medium have demonstrated a good correlation between the glutamate, glutamine and glucose concentrations measured with the chip-based biosensors in a differential-mode and the commercially available instrumentation. The obtained results demonstrate the feasibility of the realized microfluidic biosensor chip for monitoring of bioprocesses.
Y1  - 2013
U6  - http://dx.doi.org/10.1016/j.jbiotec.2012.03.014
SN  - 0168-1656
VL  - 163
IS  - 4
SP  - 371
EP  - 376
PB  - Elsevier
CY  - Amsterdam
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  - Leinhos, Marcel
A1  - Schusser, Sebastian
A1  - Bäcker, Matthias
A1  - Poghossian, Arshak
A1  - Schöning, Michael Josef
T1  - Micromachined multi-parameter sensor chip for the control of polymer-degradation medium
JF  - Physica Status Solidi (A) : special issue on engineering and functional interfaces
N2  - It is well known that the degradation environment can strongly influence the biodegradability and kinetics of biodegradation processes of polymers. Therefore, besides the monitoring of the degradation process, it is also necessary to control the medium in which the degradation takes place. In this work, a micromachined multi-parameter sensor chip for the control of the polymer-degradation medium has been developed. The chip combines a capacitive field-effect pH sensor, a four-electrode electrolyte-conductivity sensor and a thin-film Pt-temperature sensor. The results of characterization of individual sensors are presented. In addition, the multi-parameter sensor chip together with an impedimetric polymer-degradation sensor was simultaneously characterized in degradation solutions with different pH and electrolyte conductivity. The obtained results demonstrate the feasibility of the multi-parameter sensor chip for the control of the polymer-degradation medium.
Y1  - 2014
U6  - http://dx.doi.org/10.1002/pssa.201330364
SN  - 1521-396X (E-Journal); 1862-6319 (E-Journal); 0031-8965 (Print); 1862-6300 (Print)
VL  - 211
IS  - 6
SP  - 1346
EP  - 1351
PB  - Wiley-VCH
CY  - Weinheim
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  - http://dx.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  - Bäcker, Matthias
A1  - Kramer, F.
A1  - Huck, Christina
A1  - Poghossian, Arshak
A1  - Bratov, A.
A1  - Abramova, N.
A1  - Schöning, Michael Josef
T1  - Planar and 3D interdigitated electrodes for biosensing applications: The impact of a dielectric barrier on the sensor properties
JF  - Physica Status Solidi (A) - Applications and Materials Science
N2  - Planar and three-dimensional (3D) interdigitated electrodes (IDE) with electrode digits separated by an insulating barrier of different heights were electrochemically characterized and compared in terms of their sensing properties. Due to the impact of the surface resistance, both types of IDE structures display a non-linear behavior in low-ionic strength solutions. The experimental data were fitted to an electrical equivalent circuit and interpreted taking into account the surface-charge-governed properties. The effect of a charged polyelectrolyte layer electrostatically assembled onto the sensor surface on the surface resistance in solutions with different KCl concentration is studied. In case of the same electrode footprint, 3D-IDEs show a larger cell constant and a higher sensitivity to molecular adsorption than that of planar IDEs. The obtained results demonstrate the potential of 3D-IDEs as a new transducer structure for a direct label-free sensing of charged molecules.
Y1  - 2014
U6  - http://dx.doi.org/10.1002/pssa.201330416
SN  - 1521-396X (E-Journal); 1862-6319 (E-Journal); 0031-8965 (Print); 1862-6300 (Print)
VL  - 211
IS  - 6
SP  - 1357
EP  - 1363
PB  - Wiley-VCH
CY  - Weinheim
ER  -