TY  - JOUR
A1  - Welden, Rene
A1  - Schöning, Michael Josef
A1  - Wagner, Patrick H.
A1  - Wagner, Torsten
T1  - Light-Addressable Electrodes for Dynamic and Flexible Addressing of Biological Systems and Electrochemical Reactions
JF  - Sensors
N2  - In this review article, we are going to present an overview on possible applications of light-addressable electrodes (LAE) as actuator/manipulation devices besides classical electrode structures. For LAEs, the electrode material consists of a semiconductor. Illumination with a light source with the appropiate wavelength leads to the generation of electron-hole pairs which can be utilized for further photoelectrochemical reaction. Due to recent progress in light-projection technologies, highly dynamic and flexible illumination patterns can be generated, opening new possibilities for light-addressable electrodes. A short introduction on semiconductor–electrolyte interfaces with light stimulation is given together with electrode-design approaches. Towards applications, the stimulation of cells with different electrode materials and fabrication designs is explained, followed by analyte-manipulation strategies and spatially resolved photoelectrochemical deposition of different material types.
Y1  - 2020
U6  - http://dx.doi.org/10.3390/s20061680
SN  - 1424-8220
VL  - 20
IS  - 6
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Welden, Rene
A1  - Scheja, Sabrina
A1  - Schöning, Michael Josef
A1  - Wagner, Patrick
A1  - Wagner, Torsten
T1  - Electrochemical Evaluation of Light‐Addressable Electrodes Based on TiO2 for the Integration in Lab‐on‐Chip Systems
JF  - physica status solidi a : applications and materials sciences
N2  - In lab-on-chip systems, electrodes are important for the manipulation (e.g., cell stimulation, electrolysis) within such systems. An alternative to commonly used electrode structures can be a light-addressable electrode. Here, due to the photoelectric effect, the conducting area can be adjusted by modification of the illumination area which enables a flexible control of the electrode. In this work, titanium dioxide based light-addressable electrodes are fabricated by a sol–gel technique and a spin-coating process, to deposit a thin film on a fluorine-doped tin oxide glass. To characterize the fabricated electrodes, the thickness, and morphological structure are measured by a profilometer and a scanning electron microscope. For the electrochemical behavior, the dark current and the photocurrent are determined for various film thicknesses. For the spatial resolution behavior, the dependency of the photocurrent while changing the area of the illuminated area is studied. Furthermore, the addressing of single fluid compartments in a three-chamber system, which is added to the electrode, is demonstrated.
Y1  - 2018
U6  - http://dx.doi.org/10.1002/pssa.201800150
SN  - 1862-6319
VL  - 215
IS  - 15
SP  - Article number 1800150
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Welden, Rene
A1  - Nagamine Komesu, Cindy A.
A1  - Wagner, Patrick H.
A1  - Schöning, Michael Josef
A1  - Wagner, Torsten
T1  - Photoelectrochemical enzymatic penicillin biosensor: A proof-of-concept experiment
JF  - Electrochemical Science Advances
N2  - Photoelectrochemical (PEC) biosensors are a rather novel type of biosensors thatutilizelighttoprovideinformationaboutthecompositionofananalyte,enablinglight-controlled multi-analyte measurements. For enzymatic PEC biosensors,amperometric detection principles are already known in the literature. In con-trast, there is only a little information on H+-ion sensitive PEC biosensors. Inthis work, we demonstrate the detection of H+ions emerged by H+-generatingenzymes, exemplarily demonstrated with penicillinase as a model enzyme on atitanium dioxide photoanode. First, we describe the pH sensitivity of the sensorand study possible photoelectrocatalytic reactions with penicillin. Second, weshow the enzymatic PEC detection of penicillin.
KW  - enzymatic biosensor
KW  - penicillin
KW  - penicillinase
KW  - photoelectrochemistry
KW  - titanium dioxide photoanode
Y1  - 2021
U6  - http://dx.doi.org/10.1002/elsa.202100131
SN  - 2698-5977
N1  - Corresponding auhtor: Michael J. Schöning
VL  - 2
IS  - 4
SP  - 1
EP  - 5
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Welden, Rene
A1  - Jablonski, Melanie
A1  - Wege, Christina
A1  - Keusgen, Michael
A1  - Wagner, Patrick Hermann
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
T1  - Light-Addressable Actuator-Sensor Platform for Monitoring and Manipulation of pH Gradients in Microfluidics: A Case Study with the Enzyme Penicillinase
JF  - Biosensors
N2  - The feasibility of light-addressed detection and manipulation of pH gradients inside an electrochemical microfluidic cell was studied. Local pH changes, induced by a light-addressable electrode (LAE), were detected using a light-addressable potentiometric sensor (LAPS) with different measurement modes representing an actuator-sensor system. Biosensor functionality was examined depending on locally induced pH gradients with the help of the model enzyme penicillinase, which had been immobilized in the microfluidic channel. The surface morphology of the LAE and enzyme-functionalized LAPS was studied by scanning electron microscopy. Furthermore, the penicillin sensitivity of the LAPS inside the microfluidic channel was determined with regard to the analyte’s pH influence on the enzymatic reaction rate. In a final experiment, the LAE-controlled pH inhibition of the enzyme activity was monitored by the LAPS.
KW  - microfluidics
KW  - enzyme kinetics
KW  - actuator-sensor system
KW  - light-addressable electrode
KW  - light-addressable potentiometric sensor
Y1  - 2021
U6  - http://dx.doi.org/10.3390/bios11060171
SN  - 2079-6374
N1  - This article belongs to the Special Issue "Selected Papers from the 1st International Electronic Conference on Biosensors (IECB 2020)"
VL  - 11
IS  - 6
PB  - MDPI
CY  - Basel
ER  - 
TY  - CHAP
A1  - Wagner, Torsten
A1  - Yoshinobu, T.
A1  - Schöning, Michael Josef
T1  - Light-addressable potentiometric sensor as semiconductor-based sensor platform for (bio-) chemical sensing
T2  - Armenian Journal of Physics
Y1  - 2008
SN  - 1829-1171
SP  - 99
EP  - 103
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Yoshinobu, T.
A1  - Rao, C.
A1  - Otto, R.
A1  - Schöning, Michael Josef
T1  - „All-in-one“ solid-state device based on a lightaddressable potentiometric sensor platform
JF  - Transducers '05 : the 13th International Conference on Solid-State Sensors, Actuators and Microsystems ; Seoul, Korea, [June 5 - 9, 2005] ; digest of technical papers / sponsored by Korean Sensors Society. Technical co-sponsors: IEEE Electron Devices Society
Y1  - 2005
SN  - 0-7803-83995-6
N1  - International Conference on Solid State Sensors, Actuators and Microsystems ; (13, 2005, Seoul)
SP  - 1872
EP  - 1875
PB  - IEEE Operations Center
CY  - Piscataway, NJ
ER  - 
TY  - CHAP
A1  - Wagner, Torsten
A1  - Yoshinobu, T.
A1  - Otto, R.
A1  - Rao, C.
A1  - Molina, R.
A1  - Schöning, Michael Josef
T1  - Licht-adressierbare potentiometrische Sensorsysteme – Konzepte und Anwendungen
T2  - Sensoren und Mess-Systeme 2006 : Vorträge der 13. ITG/GMA-Fachtagung vom 13. bis 14.3.2006 in Freiburg/Breisgau
Y1  - 2006
SN  - 3-8007-2939-3
SP  - 165
EP  - 168
PB  - VDE Verl.
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Werner, Frederik
A1  - Miyamoto, Ko-Ichiro
A1  - Schöning, Michael Josef
A1  - Yoshinobu, Tatsuo
T1  - Development and characterisation of a compact light-addressable potentiometric sensor (LAPS) based on the digital light processing (DLP) technology for flexible chemical imaging
JF  - Sensors and Actuators B: Chemical
N2  - Chemical imaging systems allow the visualisation of the distribution of chemical species on the sensor surface. This work represents a new flexible approach to read out light-addressable potentiometric sensors (LAPS) with the help of a digital light processing (DLP) set-up. The DLP, known well for video projectors, consists of a mirror-array MEMS device, which allows fast and flexible generation of light patterns. With the help of these light patterns, the sensor surface of the LAPS device can be addressed. The DLP approach has several advantages compared to conventional LAPS set-ups, e.g., the spot size and the shape of the light pointer can be changed easily and no mechanical movement is necessary, which reduces the size of the set-up and increases the stability and speed of the measurement. In addition, the modulation frequency and intensity of the light beam are important parameters of the LAPS set-up. Within this work, the authors will discuss two different ways of light modulation by the DLP set-up, investigate the influence of different modulation frequencies and different light intensities as well as demonstrate the scanning capabilities of the new set-up by pH mapping on the sensor surface.
Y1  - 2012
U6  - http://dx.doi.org/10.1016/j.snb.2010.12.003
SN  - 0925-4005
N1  - Part of special issue "Eurosensors XXIV, 2010"
VL  - 170
SP  - 34
EP  - 39
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Werner, Frederik
A1  - Miyamoto, Ko-Ichiro
A1  - Schöning, Michael Josef
A1  - Yoshinobu, Tatsuo
T1  - A high-density multi-point LAPS set-up using a VCSEL array and FPGA control
JF  - Sensors and Actuators B: Chemical. 154 (2011), H. 2
Y1  - 2011
SN  - 1873-3077
N1  - EUROSENSORS XXIII
SP  - 124
EP  - 128
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Werner, Frederik
A1  - Miyamoto, Ko-ichiro
A1  - Ackermann, Hans-Josef
A1  - Yoshinobu, Tatsuo
A1  - Schöning, Michael Josef
T1  - FPGA-based LAPS device for the flexible design of sensing sites on functional interfaces
JF  - Physica Status Solidi (A). 207 (2010), H. 4
Y1  - 2010
SN  - 1862-6300
N1  - Special Issue: Engineering of Functional Interfaces EnFI 2009
SP  - 844
EP  - 849
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Werner, Frederik
A1  - Miyamoto, K.
A1  - Schöning, Michael Josef
A1  - Yoshinobu, T.
T1  - A high-density multi-point LAPS set-up using a VCSEL array and FPGA control
JF  - Procedia Chemistry. 1 (2009), H. 1
Y1  - 2009
SN  - 1876-6196
N1  - Proceedings of the Eurosensors XXIII conference ; Eurosensors 23
SP  - 1483
EP  - 1486
PB  - Elsevier
CY  - Amsterdam
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  - Wagner, Torsten
A1  - Shigiahara, N.
A1  - Miyamoto, K.
A1  - Suzurikawa, J.
A1  - Finger, F.
A1  - Schöning, Michael Josef
A1  - Yoshinobu, T.
T1  - Light-addressable Potentiometric Sensors and Light–addressable Electrodes as a Combined Sensor-and-manipulator Microsystem with High Flexibility
JF  - Procedia Engineering
N2  - This work describes the novel combination of the light-addressable electrode (LAE) and the light-addressable potentiometric sensor (LAPS) into a microsystem set-up. Both the LAE as well as the LAPS shares the principle of addressing the active spot by means of a light beam. This enables both systems to manipulate resp. to detect an analyte with a high spatial resolution. Hence, combining both principles into a single set-up enables the active stimulation e.g., by means of electrolysis and a simultaneous observation e.g., the response of an entrapped biological cell by detection of extracellular pH changes. The work will describe the principles of both technologies and the necessary steps to integrate them into a single set-up. Furthermore, examples of application and operation of such systems will be presented.
Y1  - 2012
U6  - http://dx.doi.org/10.1016/j.proeng.2012.09.290
SN  - 1877-7058
N1  - Part of special issue "26th European Conference on Solid-State Transducers, EUROSENSOR 2012"
IS  - 47
SP  - 890
EP  - 893
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
A1  - Otto, R.
A1  - Yoshinobu, T.
T1  - A handheld 16 channel pen-type LAPS as a platform for (bio-)electrochemical sensing
JF  - Biomedizinische Technik. 49 (2004), H. 2
Y1  - 2004
SN  - 0932-4666
SP  - 996
EP  - 997
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
T1  - Light-addressable potentiometric sensors (LAPS): recent trends and applications
JF  - Electrochemical sensor analysis / edited by S. Alegret ...
Y1  - 2007
SN  - 978-0-444-53053-0
N1  - Wilson & Wilson's comprehensive analytical chemistry ; 49
SP  - 87
EP  - 128
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - CHAP
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
T1  - Preface of the Special Issue of I3S 2005 in Jülich (Germany)
N2  - International Symposium on Sensor Science, I3S 2005 <3; 2005; Juelich, Germany> In: Sensors 2006, 6, 260-261 ISSN 1424-8220
KW  - Biosensor
KW  - I3S 2005
KW  - International Symposium on Sensor Science
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:a96-opus-1365
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Rao, C.
A1  - Otto, R.
A1  - Yoshinobu, T.
A1  - Kloock, Joachim P.
A1  - Schöning, Michael Josef
T1  - Chipkarten-basierter Multikanal lichtadressierbarer potentiometrischer Sensor für analytische Anwendungen in flüssigen Medien
JF  - Neue Herausforderungen und Anwendungen in der Sensortechnik : 7. Dresdner Sensor-Symposium ; 12. - 14. Dezember 2005, Dresden / [Forschungsgesellschaft für Messtechnik, Sensorik und Medizintechnik e.V.]. Gerald Gerlach ... (Hg.)
Y1  - 2005
SN  - 3-938863-29-3
N1  - Dresdner Beiträge zur Sensorik ; 24
SP  - 11
EP  - 14
PB  - TUDpress
CY  - Dresden
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Rao, C.
A1  - Kloock, Joachim P.
A1  - Yoshinobu, T.
A1  - Otto, R.
A1  - Keusgen, M.
A1  - Schöning, Michael Josef
T1  - “LAPS Card”—A novel chip card-based light-addressable potentiometric sensor (LAPS)
JF  - Sensors and Actuators B: Chemical. 118 (2006), H. 1-2
Y1  - 2006
SN  - 0925-4005
N1  - Eurosensors XIX - Eurosensors XIX - The 19th European Conference on Solid-State Transducers
SP  - 33
EP  - 40
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Molina, Roberto
A1  - Yoshinobu, Tatsuo
A1  - Kloock, Joachim P.
A1  - Biselli, Manfred
A1  - Canzoneri, Michele
A1  - Schnitzler, Thomas
A1  - Schöning, Michael Josef
T1  - Handheld multi-channel LAPS device as a transducer platform for possible biological and chemical multi-sensor applications
JF  - Electrochimica Acta. 53 (2007), H. 2
Y1  - 2007
SN  - 0013-4686
SP  - 305
EP  - 311
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Molina, R.
A1  - Biselli, Manfred
A1  - Canzoneri, Michele
A1  - Schnitzler, Thomas
A1  - Yoshinobu, Tatsuo
A1  - Schöning, Michael Josef
T1  - A light-addressable potentiometric sensor system for fast, simultaneous and spatial detection of the metabolic activity of biological cells
JF  - Transducers '07 Eurosensors XXI : digest of technical papers ; the14th International Conference on Solid-State Sensors, Actuators and Microsystems, June 10-14, 2007, Lyon, France / Gilles Delapierre (Ed.)
Y1  - 2007
SN  - 1-4244-0841-5
N1  - Eurosensors 21, 2007, Lyon ; International Conference on Solid-State Sensors, Actuators and Microsystems 14, 2007, Lyon
SP  - 1107
EP  - 1110
PB  - IEEE
CY  - Piscataway
ER  -