TY  - JOUR
A1  - Dantism, Shahriar
A1  - Röhlen, Desiree
A1  - Wagner, Torsten
A1  - Wagner, P.
A1  - Schöning, Michael Josef
T1  - A LAPS-based differential sensor for parallelized metabolism monitoring of various bacteria
JF  - Sensors
N2  - Monitoring the cellular metabolism of bacteria in (bio)fermentation processes is crucial to control and steer them, and to prevent undesired disturbances linked to metabolically inactive microorganisms. In this context, cell-based biosensors can play an important role to improve the quality and increase the yield of such processes. This work describes the simultaneous analysis of the metabolic behavior of three different types of bacteria by means of a differential light-addressable potentiometric sensor (LAPS) set-up. The study includes Lactobacillus brevis, Corynebacterium glutamicum, and Escherichia coli, which are often applied in fermentation processes in bioreactors. Differential measurements were carried out to compensate undesirable influences such as sensor signal drift, and pH value variation during the measurements. Furthermore, calibration curves of the cellular metabolism were established as a function of the glucose concentration or cell number variation with all three model microorganisms. In this context, simultaneous (bio)sensing with the multi-organism LAPS-based set-up can open new possibilities for a cost-effective, rapid detection of the extracellular acidification of bacteria on a single sensor chip. It can be applied to evaluate the metabolic response of bacteria populations in a (bio)fermentation process, for instance, in the biogas fermentation process.
Y1  - 2019
U6  - http://dx.doi.org/10.3390/s19214692
SN  - 1424-8220
VL  - 19
IS  - 21
PB  - MDPI
CY  - Basel
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  - JOUR
A1  - Dantism, Shahriar
A1  - Röhlen, Desiree
A1  - Selmer, Thorsten
A1  - Wagner, Torsten
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Quantitative differential monitoring of the metabolic activity of Corynebacterium glutamicum cultures utilizing a light-addressable potentiometric sensor system
JF  - Biosensors and Bioelectronics
Y1  - 2019
U6  - http://dx.doi.org/10.1016/j.bios.2019.111332
VL  - 139
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Dantism, Shahriar
A1  - Röhlen, Desiree
A1  - Dahmen, Markus
A1  - Wagner, Torsten
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - LAPS-based monitoring of metabolic responses of bacterial cultures in a paper fermentation broth
JF  - Sensors and Actuators B: Chemical
N2  - As an alternative renewable energy source, methane production in biogas plants is gaining more and more attention. Biomass in a bioreactor contains different types of microorganisms, which should be considered in terms of process-stability control. Metabolically inactive microorganisms within the fermentation process can lead to undesirable, time-consuming and cost-intensive interventions. Hence, monitoring of the cellular metabolism of bacterial populations in a fermentation broth is crucial to improve the biogas production, operation efficiency, and sustainability. In this work, the extracellular acidification of bacteria in a paper-fermentation broth is monitored after glucose uptake, utilizing a differential light-addressable potentiometric sensor (LAPS) system. The LAPS system is loaded with three different model microorganisms (Escherichia coli, Corynebacterium glutamicum, and Lactobacillus brevis) and the effect of the fermentation broth at different process stages on the metabolism of these bacteria is studied. In this way, different signal patterns related to the metabolic response of microorganisms can be identified. By means of calibration curves after glucose uptake, the overall extracellular acidification of bacterial populations within the fermentation process can be evaluated.
Y1  - 2020
U6  - http://dx.doi.org/10.1016/j.snb.2020.128232
SN  - 0925-4005
VL  - 320
IS  - Art. 128232
PB  - Elsevier
CY  - Amsterdam
ER  - 
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  - 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  - 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  - Schöning, Michael Josef
A1  - Wagner, Torsten
A1  - Wang, C.
A1  - Otto, R.
A1  - Yoshinobu, T.
T1  - Development of a handheld 16 channel pen-type LAPS for electrochemical sensing
JF  - Sensors and Actuators B. 108 (2005)
Y1  - 2005
SN  - 0925-4005
SP  - 808
EP  - 814
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  - JOUR
A1  - Schöning, Michael Josef
A1  - Wagner, Torsten
A1  - Wang, C.
A1  - Otto, R.
A1  - Yoshinobu, T.
T1  - Development of a handheld 16 channel pen-type LAPS for electrochemical sensing
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  - 136
EP  - 137
PB  - Japan Association of Chemical Sensors
CY  - Fukuoka
ER  - 
TY  - JOUR
A1  - Yoshinobu, T.
A1  - Iwasaki, H.
A1  - Ui, Y.
A1  - Furuichi, K.
A1  - Ermelenko, Y.
A1  - Mourzina, Y.
A1  - Wagner, Torsten
A1  - Näther, Niko
A1  - Schöning, Michael Josef
T1  - The light-addressable potentiometric sensor for multi-ion sensing and imaging
JF  - Methods. 37 (2005), H. 1
Y1  - 2005
SN  - 1046-2023
SP  - 99
EP  - 102
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  - Kloock, Joachim P.
A1  - Moreno, Lia
A1  - Bratov, A.
A1  - Huachupoma, S.
A1  - Xu, J.
A1  - Wagner, Torsten
A1  - Yoshinobu, T.
A1  - Ermolenko, Y.
A1  - Vlasov, Y. G.
A1  - Schöning, Michael Josef
T1  - PLD-prepared cadmium sensors based on chalcogenide glasses —ISFET, LAPS and μISE semiconductor structures
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  - 149
EP  - 155
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  - 
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  - JOUR
A1  - Wagner, Torsten
A1  - Kloock, Joachim P.
A1  - Schöning, Michael Josef
T1  - Determination of cadmium concentration and pH value in aqueous solutions by means of a handheld light-addressable potentiometric sensor (LAPS) device
JF  - Electrochemical sensor analysis / edited by S. Alegret ...
Y1  - 2007
SN  - 978-0-444-53133-9
N1  - Wilson & Wilson's comprehensive analytical chemistry ; 49
SP  - e35
EP  - e44
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Maris, Rob J.
A1  - Ackermann, Hans-Josef
A1  - Otto, Ralph
A1  - Beging, Stefan
A1  - Poghossian, Arshak
A1  - Schöning, Michael Josef
T1  - Handheld measurement device for field-effect sensor structures: Practical evaluation and limitations
JF  - Sensors and Actuators B: Chemical  . 127 (2007), H. 1
Y1  - 2007
SN  - 0925-4005
SP  - 217
EP  - 223
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  -