TY  - JOUR
A1  - Schroth, P.
A1  - Lüth, H.
A1  - Hummel, Hans E.
A1  - Schütz, S.
A1  - Schöning, Michael Josef
T1  - Characterising an insect antenna as a receptor for a biosensor by means of impedance spectroscopy
JF  - Scaling down in electrochemistry : electrochemical micro- and nanosystem technology ; proceedings of the 3rd International Symposium on Electrochemical Microsystem Technologies, Garmisch-Patenkirchen, Germany, 11 - 15 September 2000 / ed. by J. W. Schultz
Y1  - 2001
SN  - 0-08-044014-2
SP  - 293
EP  - 297
PB  - Elsevier [u.a.]
CY  - Amsterdam [u.a.]
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  - 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  - Miyamoto, K.
A1  - Kuwabara, Yohei
A1  - Kanoh, Shin'ichiro
A1  - Yoshinobu, Tatsuo
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
T1  - Chemical image scanner based on FDM-LAPS
JF  - Sensors and Actuators B: Chemical. 137 (2009), H. 2
Y1  - 2009
SN  - 0925-4005
SP  - 533
EP  - 538
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Miyamoto, K.
A1  - Ichimura, H.
A1  - Wagner, Torsten
A1  - Yoshinobu, T.
A1  - Schöning, Michael Josef
T1  - Chemical Imaging of ion Diffusion in a Microfluidic Channel
JF  - Procedia Engineering
N2  - The chemical imaging sensor is a chemical sensor which is capable of visualizing the spatial distribution of chemical species in sample solution. In this study, a novel measurement system based on the chemical imaging sensor was developed to observe the inside of a Y-shaped microfluidic channel while injecting two sample solutions from two branches. From the collected chemical images, it was clearly observed that the injected solutions formed laminar flows in the microfluidic channel. In addition, ion diffusion across the laminar flows was observed. This label-free method can acquire quantitative data of ion distribution and diffusion in microfluidic devices, which can be used to determine the diffusion coefficients, and therefore, the molecular weights of chemical species in the sample solution.
Y1  - 2012
U6  - http://dx.doi.org/10.1016/j.proeng.2012.09.289
SN  - 1877-7058
N1  - Part of special issue "26th European Conference on Solid-State Transducers, EUROSENSOR 2012"
IS  - 47
SP  - 886
EP  - 889
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Miyamoto, Ko-ichiro
A1  - Ichimura, Hiroki
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
A1  - Yoshinobu, Tatsuo
T1  - Chemical imaging of the concentration profile of ion diffusion in a microfluidic channel
JF  - Sensors and actuators. B: Chemical
N2  - The chemical imaging sensor is a device to visualize the spatial distribution of chemical species based on the principle of LAPS (light-addressable potentiometric sensor), which is a field-effect chemical sensor based on semiconductor. In this study, the chemical imaging sensor has been applied to investigate the ion profile of laminar flows in a microfluidic channel. The chemical images (pH maps) were collected in a Y-shaped microfluidic channel while injecting HCl and NaCl solutions into two branches. From the chemical images, it was clearly observed that the injected solutions formed laminar flows in the channel. In addition, ion diffusion across the laminar flows was observed, and the diffusion coefficient could be derived by fitting the pH profiles to the Fick's equation.
Y1  - 2013
U6  - http://dx.doi.org/10.1016/j.snb.2013.04.057
SN  - 1873-3077 (E-Journal); 0925-4005 (Print)
N1  - Part of special issue "Selected Papers from the 26th European Conference on Solid-State Transducers"
VL  - 189
SP  - 240
EP  - 245
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Yoshinobu, T.
A1  - Ecken, H.
A1  - Ismail, Md.A.B.
A1  - Iwasaki, H.
A1  - Lüth, H.
A1  - Schöning, Michael Josef
T1  - Chemical imaging sensor and its application to biological systems
JF  - Scaling down in electrochemistry : electrochemical micro- and nanosystem technology ; proceedings of the 3rd International Symposium on Electrochemical Microsystem Technologies, Garmisch-Patenkirchen, Germany, 11 - 15 September 2000 / ed. by J. W. Schultz
Y1  - 2001
SN  - 0-08-044014-2
SP  - 259
EP  - 263
PB  - Elsevier [u.a.]
CY  - Amsterdam [u.a.]
ER  - 
TY  - JOUR
A1  - Poghossian, Arshak
A1  - Berndsen, L.
A1  - Schöning, Michael Josef
T1  - Chemical sensor as a physical sensor: ISFET-based flowvelocity, flow-direction and diffusion-coefficient sensor
JF  - Book of abstracts / ed. by J. Saneistr.
Y1  - 2002
SN  - 80-01-02576-4
N1  - Eurosensors ; (16, 2002, Praha)
SP  - 649
EP  - 652
PB  - Czech Technical University, Faculty of Electrical Engineering, Department of Measurement
CY  - Prague
ER  - 
TY  - JOUR
A1  - Poghossian, Arshak
A1  - Berndsen, Lars
A1  - Schöning, Michael Josef
T1  - Chemical sensor as physical sensor: ISFET-based flowvelocity, flow-direction and diffusion-coefficient sensor
JF  - Sensors and Actuators B. 95 (2003), H. 1-3
Y1  - 2003
SN  - 0925-4005
SP  - 384
EP  - 390
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  -