TY  - JOUR
A1  - Werner, Frederik
A1  - Krumbe, Christoph
A1  - Schumacher, Katharina
A1  - Groebel, Simone
A1  - Spelthahn, Heiko
A1  - Stellberg, Michael
A1  - Wagner, Torsten
A1  - Yoshinobu, Tatsuo
A1  - Selmer, Thorsten
A1  - Keusgen, Michael
A1  - Baumann, Marcus
A1  - Schöning, Michael Josef
T1  - Determination of the extracellular acidification of Escherichia coli by a light-addressable potentiometric sensor
JF  - Physica status solidi (a) : applications and material science. 208 (2011), H. 6
Y1  - 2011
SN  - 1862-6319
SP  - 1340
EP  - 1344
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - CHAP
A1  - Werner, Frederik
A1  - Mansour, Ahmed
A1  - Rateike, Franz-Matthias
A1  - Schusser, Sebastian
A1  - Wagner, Torsten
A1  - Yoshinobu, Tatsuo
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
ED  - Gerlach, Gerald
T1  - Kompakter Aufbau eines lichtadressierbaren potentiometrischen Sensors mit verfahrbarem Diodenlaser
T2  - 10. Dresdner Sensor-Symposium : Dresden, 5. - 7. Dezember 2011 ; miniaturisierte analytische Verfahren, Hochtemperatur-Sensoren, Sensoren für Bioprozess- und Verfahrenstechnik, Sensoren für die Medizin, Chemische Verfahrenstechnik, Lebensmittelanalytik, innovative Sensorlösungen, Sensoren für die Wasserqualität, Selbstüberwachung / Gerald Gerlach ... (Hg.) Dresdner Beiträge zur Sensorik. 43
Y1  - 2011
SN  - 978-3-942710-53-4
SP  - 277
EP  - 280
PB  - TUDpress
CY  - Dresden
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Vornholt, Wolfgang
A1  - Werner, Frederik
A1  - Yoshinobu, Tatsuo
A1  - Miyamoto, Ko-Ichiro
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Light-addressable potentiometric sensor (LAPS) combined with magnetic beads for pharmaceutical screening
JF  - Physics in medicine
N2  - The light-addressable potentiometric sensor (LAPS) has the unique feature to address different regions of a sensor surface without the need of complex structures. Measurements at different locations on the sensor surface can be performed in a common analyte solution, which distinctly simplifies the fluidic set-up. However, the measurement in a single analyte chamber prevents the application of different drugs or different concentrations of a drug to each measurement spot at the same time as in the case of multi-reservoir-based set-ups. In this work, the authors designed a LAPS-based set-up for cell culture screening that utilises magnetic beads loaded with the endotoxin (lipopolysaccharides, LPS), to generate a spatially distributed gradient of analyte concentration. Different external magnetic fields can be adjusted to move the magnetic beads loaded with a specific drug within the measurement cell. By recording the metabolic activities of a cell layer cultured on top of the LAPS surface, this work shows the possibility to apply different concentrations of a sample along the LAPS measurement spots within a common analyte solution.
Y1  - 2016
U6  - http://dx.doi.org/10.1016/j.phmed.2016.03.001
SN  - 2352-4510
VL  - 2016
IS  - 1
SP  - 2
EP  - 7
ER  - 
TY  - JOUR
A1  - Werner, Frederik
A1  - Wagner, Torsten
A1  - Yoshinobu, Tatsuo
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Frequency behaviour of light-addressable potentiometric sensors
JF  - Physica Status Solidi (A)
N2  - Light-addressable potentiometric sensors (LAPS) are semiconductor-based potentiometric sensors, with the advantage to detect the concentration of a chemical species in a liquid solution above the sensor surface in a spatially resolved manner. The addressing is achieved by a modulated and focused light source illuminating the semiconductor and generating a concentration-depending photocurrent. This work introduces a LAPS set-up that is able to monitor the electrical impedance in addition to the photocurrent. The impedance spectra of a LAPS structure, with and without illumination, as well as the frequency behaviour of the LAPS measurement are investigated. The measurements are supported by electrical equivalent circuits to explain the impedance and the LAPS-frequency behaviour. The work investigates the influence of different parameters on the frequency behaviour of the LAPS. Furthermore, the phase shift of the photocurrent, the influence of the surface potential as well as the changes of the sensor impedance will be discussed.
Y1  - 2013
U6  - http://dx.doi.org/10.1002/pssa.201200929
SN  - 1521-396X ; 0031-8965
VL  - 210
IS  - 5
SP  - 884
EP  - 891
PB  - Wiley-VCH
CY  - Weinheim
ER  -