TY  - JOUR
A1  - Dantism, S.
A1  - Takenaga, S.
A1  - Wagner, P.
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
T1  - Light-addressable Potentiometric Sensor (LAPS) Combined with Multi-chamber Structures to Investigate the Metabolic Activity of Cells
JF  - Procedia Engineering
N2  - LAPS are field-effect-based potentiometric sensors which are able to monitor analyte concentrations in a spatially resolved manner. Hence, a LAPS sensor system is a powerful device to record chemical imaging of the concentration of chemical species in an aqueous solution, chemical reactions, or the growth of cell colonies on the sensor surface, to record chemical images. In this work, multi-chamber 3D-printed structures made out of polymer (PP-ABS) were combined with LAPS chips to analyse differentially and simultaneously the metabolic activity of Escherichia coli K12 and Chinese hamster ovary (CHO) cells, and the responds of those cells to the addition of glucose solution.
Y1  - 2015
U6  - https://doi.org/10.1016/j.proeng.2015.08.647
SN  - 1877-7058
N1  - Part of special issue "Eurosensors 2015"
VL  - 120
SP  - 384
EP  - 387
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  - https://doi.org/10.1016/j.phmed.2016.03.001
SN  - 2352-4510
VL  - 2016
IS  - 1
SP  - 2
EP  - 7
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  - https://doi.org/10.3390/s20061680
SN  - 1424-8220
VL  - 20
IS  - 6
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  - https://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  - Kämper, Klaus-Peter
A1  - Ehrfeld, W.
A1  - Lehr, H.
A1  - Michel, F.
T1  - LIGA-Technik zur Fertigung von Mikroaktoren. Ehrfeld. W.; Kämper, K.-P.; Lehr, H.; Michel, F.
JF  - Mikroelektronik . 7 (1993), H. 5
Y1  - 1993
SN  - 0931-2714
SP  - LXIX
EP  - LXXI
ER  - 
TY  - JOUR
A1  - Kämper, Klaus-Peter
A1  - Schulz, C.
A1  - Ehrfeld, W.
A1  - Erbel, R.
T1  - LIGA Fabricated Microsystems for Medical and Related Applications. Schulz, C.; Ehrfeld, W.; Erbel, R.; Kämper, K.-P.; Koch, L.; Lehr, H.; Roth, T.
JF  - 3-Day Course on Microengineering in Medicine and Biology and its Applications to Minimally Invasive Techniques for Therapy and Medical Diagnosis : EURO-BME 94; October 5, 6, and 7, 1994, Swiss Federal Institute of Technology, EPFL, Lausanne, Switzerland / [the 1994 EURO-BME Microengineering in Medicine and Biology Training Course. Staff: Christian D. Depeursinge ...]
Y1  - 1994
N1  - Microengineering in Medicine and Biology Training Course 1994, Lausanne
PB  - REPRO EPFL
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Kämper, Klaus-Peter
A1  - Hagemann, B.
A1  - Lehr, H.
A1  - Michel, F.
T1  - LIGA Example 2: Electromagnetic Micromotor. Hagemann, B.; Kämper, K.-P.; Lehr, H.; Michel, F.; Thürigen, C.
JF  - LIGA technique / Hans-Dieter Bauer (ed.). [Developed by UETP-MEMS, University Training Partnership for Micro-Electro-Mechanical Systems ...]. - 2.ed.
Y1  - 1995
N1  - University Enterprise Training Partnership for Micro-Electro-Mechanical Systems
SP  - 100
EP  - 110
PB  - FSRM
CY  - Neuchatel
ER  - 
TY  - JOUR
A1  - Kämper, Klaus-Peter
A1  - Lehr, H.
A1  - Ehrfeld, W.
A1  - Michel, F.
T1  - LIGA Components for the Construction of Milliactuators. Lehr, H.; Ehrfeld, W.; Kämper, K.-P.; Michel, F.; Schmidt, M.
JF  - 1994 IEEE Symposium on Emerging Technologies & Factory Automation : novel disciplines for the next century ; proceedings, November 6 - 10, 1994, Tokyo, Japan / ETFA '94. Hiroyuki Fujita [chairman] ... Sponsored by: Institute of Industrial Science, SEIKEN
Y1  - 1994
SN  - 0780321146
SP  - 43
EP  - 47
CY  - Piscataway, N.J.
ER  - 
TY  - JOUR
A1  - Lepke, Dietrich
A1  - Lillie, Dirk
A1  - Peterson, Leif Arne
A1  - Hempe, Thomas
T1  - Liegedauer von Holzschwellen in Tunneln der Hamburger Hochbahn AG
JF  - EI - Der Eisenbahningenieur
N2  - Die Hamburger Hochbahn AG benötigte im Rahmen der Überarbeitung einer langfristigen Instandhaltungs- und Erneuerungsstrategie für ihre U-Bahn-Infrastruktur eine belastbare Aussage über die Restlebensdauer der Holzschwellen im Tunnel. Aus diesem Grunde beauftragte sie das Institut für Verkehrswesen, Eisenbahnbau und -betrieb (IVE) der Universität Hannover mit der Erstellung eines entsprechenden Gutachtens. Das Ergebnis führte zu der gesicherten Aussage einer erheblich längeren Restlebensdauer der Tunnelschwellen gegenüber den bisherigen, geschätzten Annahmen.
Y1  - 2006
SN  - 0013-2810
IS  - 2
SP  - 46
EP  - 50
PB  - DVV Media Group
CY  - Hamburg
ER  - 
TY  - JOUR
A1  - Anik, Sabri
A1  - Tuelbentci, K.
T1  - Lichtbogenschweißen : Untersuchung der Schweißschlacke und der Wirkungen auf das Entfernen der Schlacke beim Lichtbogenschweißen ; Teil 1
JF  - Technische Rundschau : TR ; das Schweizer Industrie-Magazin
Y1  - 1973
SN  - 0040-148X
VL  - 65
IS  - 48
SP  - 13
EP  - 15
PB  - Medtrix Group
CY  - Basel
ER  -