• Deutsch
Login

Open Access

  • Home
  • Search
  • Browse
  • Publish
  • FAQ

Refine

Author

  • Schöning, Michael Josef (19)
  • Wagner, P. (12)
  • Wagner, Torsten (9)
  • Poghossian, Arshak (8)
  • Kloock, Joachim P. (7)
  • Bäcker, Matthias (6)
  • Schusser, Sebastian (4)
  • Biselli, Manfred (3)
  • Bohrn, Ulrich (3)
  • Fleischer, M. (3)
+ more

Year of publication

  • 2019 (1)
  • 2018 (1)
  • 2015 (2)
  • 2014 (2)
  • 2013 (1)
  • 2012 (3)
  • 2011 (1)
  • 2009 (1)
  • 2007 (3)
  • 2006 (3)
+ more

Institute

  • Fachbereich Medizintechnik und Technomathematik (19)
  • INB - Institut für Nano- und Biotechnologien (15)
  • Fachbereich Chemie und Biotechnologie (2)
  • Fachbereich Luft- und Raumfahrttechnik (1)
  • IfB - Institut für Bioengineering (1)

Has Fulltext

  • no (20)

Language

  • English (17)
  • German (3)

Document Type

  • Article (16)
  • Conference Proceeding (4)

Keywords

  • Field-effect sensor (1)
  • Mars (1)
  • enzymatic (bio)degradation (1)
  • habitability (1)
  • icy moons (1)
  • impedance spectroscopy (1)
  • in-situ monitoring (1)
  • life detection (1)
  • poly(d, l-lactic acid) (1)
  • space missions (1)
+ more

Zugriffsart

  • campus (9)
  • weltweit (5)
  • bezahl (1)

Is part of the Bibliography

  • yes (11)
  • no (9)

20 search hits

  • 1 to 10
  • BibTeX
  • CSV
  • RIS
  • 10
  • 20
  • 50
  • 100

Sort by

  • Year
  • Year
  • Title
  • Title
  • Author
  • Author
A LAPS-based differential sensor for parallelized metabolism monitoring of various bacteria (2019)
Dantism, Shahriar ; Röhlen, Desiree ; Wagner, Torsten ; Wagner, P. ; Schöning, Michael Josef
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.
Light-addressable Potentiometric Sensor (LAPS) Combined with Multi-chamber Structures to Investigate the Metabolic Activity of Cells (2015)
Dantism, Shahriar ; Takenaga, S. ; Wagner, P. ; Wagner, Torsten ; Schöning, Michael Josef
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.
Capacitively coupled electrolyte-conductivity sensor based on high-k material of barium strontium titanate (2014)
Huck, Christina ; Poghossian, Arshak ; Bäcker, Matthias ; Chaudhuri, S. ; Zander, W. ; Schubert, J. ; Begoyan, Vardges K. ; Buniatyan, Vahe Vazgen ; Wagner, P. ; Schöning, Michael Josef
Enzymatically catalyzed degradation of biodegradable polymers investigated by means of a semiconductor-based field-effect sensor (2014)
Schusser, Sebastian ; Bäcker, Matthias ; Krischer, M. ; Wenzel, L. ; Leinhos, Marcel ; Poghossian, Arshak ; Biselli, Manfred ; Wagner, P. ; Schöning, Michael Josef
A semiconductor field-effect device has been used for an enzymatically catalyzed degradation of biopolymers for the first time. This novel technique is capable to monitor the degradation process of multiple samples in situ and in real-time. As model system, the degradation of the biopolymer poly(D, L-lactic acid) has been monitored in the degradation medium containing the enzyme lipase from Rhizomucor miehei. The obtained results demonstrate the potential of capacitive field-effect sensors for degradation studies of biodegradable polymers.
An application of field-effect sensors for in-situ monitoring of degradation of biopolymers (2015)
Schusser, Sebastian ; Poghossian, Arshak ; Bäcker, Matthias ; Krischer, M. ; Leinhos, Marcel ; Wagner, P. ; Schöning, Michael Josef
The characterization of the degradation kinetics of biodegradable polymers is mandatory with regard to their proper application. In the present work, polymer-modified electrolyte–insulator–semiconductor (PMEIS) field-effect sensors have been applied for in-situ monitoring of the pH-dependent degradation kinetics of the commercially available biopolymer poly(d,l-lactic acid) (PDLLA) in buffer solutions from pH 3 to pH 13. PDLLA films of 500 nm thickness were deposited on the surface of an Al–p-Si–SiO2–Ta2O5 structure from a polymer solution by means of spin-coating method. The PMEIS sensor is, in principle, capable to detect any changes in bulk, surface and interface properties of the polymer induced by degradation processes. A faster degradation has been observed for PDLLA films exposed to alkaline solutions (pH 9, pH 11 and pH 13).
Degradation of thin poly(lactic acid) films: characterization by capacitance-voltage, atomic force microscopy, scanning electron microscopy and contact-angle measurements (2013)
Schusser, Sebastian ; Menzel, S. ; Bäcker, Matthias ; Leinhos, Marcel ; Poghossian, Arshak ; Wagner, P. ; Schöning, Michael Josef
A semiconductor-based field-effect platform for (bio-)chemical and physical sensors: From capacitive EIS sensors and LAPS over ISFETs to nano-scale devices (2006)
Schöning, Michael Josef ; Abouzar, Maryam H. ; Wagner, Torsten ; Näther, Niko ; Rolka, David ; Yoshinobu, Tatsuo ; Kloock, Joachim P. ; Turek, Monika ; Ingebrandt, Sven ; Poghossian, Arshak
Halbleiterbasierte Schwermetallsensorik auf der Basis von Chalkogenidgläsern für zukünftige „Lab on Chip“-Anwendungen (2005)
Kloock, Joachim P. ; Moreno, Lia ; Huachupoma, Samuel ; Xu, Jing ; Wagner, Torsten ; Bratov, Andrey V. ; Doll, Theodor ; Vlasov, Yuri G. ; Schöning, Michael Josef
Microfluidic chip with integrated microvalves based on temperature- and pH-responsive hydrogel thin films (2012)
Bäcker, Matthias ; Raue, Markus ; Schusser, Sebastian ; Jeitner, C. ; Breuer, Lars ; Wagner, P. ; Poghossian, Arshak ; Förster, Arnold ; Mang, Thomas ; Schöning, Michael Josef
Two types of microvalves based on temperature-responsive poly(N-isopropylacrylamide) (PNIPAAm) and pH-responsive poly(sodium acrylate) (PSA) hydrogel films have been developed and tested. The PNIPAAm and PSA hydrogel films were prepared by means of in situ photopolymerization directly inside the fluidic channel of a microfluidic chip fabricated by combining Si and SU-8 technologies. The swelling/shrinking properties and height changes of the PNIPAAm and PSA films inside the fluidic channel were studied at temperatures of deionized water from 14 to 36 °C and different pH values (pH 3–12) of Titrisol buffer, respectively. Additionally, in separate experiments, the lower critical solution temperature (LCST) of the PNIPAAm hydrogel was investigated by means of a differential scanning calorimetry (DSC) and a surface plasmon resonance (SPR) method. Mass-flow measurements have shown the feasibility of the prepared hydrogel films to work as an on-chip integrated temperature- or pH-responsive microvalve capable to switch the flow channel on/off.
Monitoring of irritant gas using a whole-cell-based sensor system (2012)
Bohrn, Ulrich ; Stütz, Evamaria ; Fuchs, Karen ; Fleischer, M. ; Schöning, Michael Josef ; Wagner, P.
Cell-based sensors for the detection of gases have long been underrepresented, due to the cellular requirement of being cultured in a liquid environment. In this work we established a cell-based gas biosensor for the detection of toxic substances in air, by adapting a commercial sensor chip (Bionas®), previously used for the measurement of pollutants in liquids. Cells of the respiratory tract (A549, RPMI 2650, V79), which survive at a gas phase in a natural context, are used as biological receptors. The physiological cell parameters acidification, respiration and morphology are continuously monitored in parallel. Ammonia was used as a highly water-soluble model gas to test the feasibility of the sensor system. Infrared measurements confirmed the sufficiency of the medium draining method. This sensor system provides a basis for many sensor applications such as environmental monitoring, building technology and public security.
  • 1 to 10

OPUS4 Logo

  • Contact
  • Imprint
  • Sitelinks