TY  - JOUR
A1  - Bronder, Thomas
A1  - Poghossian, Arshak
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Label-free detection of double-stranded DNA molecules with polyelectrolyte-modified capacitive field-effect sensors
T1  - Markierungsfreie Detektion doppelsträngiger DNA Moleküle mit Hilfe von Polyelektrolyt-modifizierten kapazitiven Feldeffekt-Sensoren
JF  - tm - Technisches Messen
N2  - In this study, polyelectrolyte-modified field-effect-based electrolyte-insulator-semiconductor (EIS) devices have been used for the label-free electrical detection of double-stranded deoxyribonucleic acid (dsDNA)molecules. The sensor-chip functionalization with a positively charged polyelectrolyte layer provides the possibility of direct adsorptive binding of negatively charged target DNA oligonucleotides onto theSiO2-chip surface.EIS sensors can be utilized as a tool to detect surface-charge changes; the electrostatic adsorption of oligonucleotides onto the polyelectrolyte layer leads to a measureable surface-potential change. Signals of 39mV have been recorded after the incubation with the oligonucleotide solution. Besides the electrochemical experiments, the successful adsorption of dsDNA onto the polyelectrolyte layer has been verified via fluorescence microscopy. The presented results demonstrate that the signal recording of EISchips, which are modified with a polyelectrolyte layer, canbe used as a favorable approach for a fast, cheap and simple detection method for dsDNA.
Y1  - 2017
U6  - https://doi.org/10.1515/teme-2017-0015
VL  - 84
IS  - 10
SP  - 628
EP  - 634
PB  - De Gruyter
CY  - Oldenbourg
ER  - 
TY  - JOUR
A1  - Bronder, Thomas
A1  - Poghossian, Arshak
A1  - Jessing, Max P.
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Surface regeneration and reusability of label-free DNA biosensors based on weak polyelectrolyte-modified capacitive field-effect structures
JF  - Biosensors and Bioelectronics
Y1  - 2019
U6  - https://doi.org/10.1016/j.bios.2018.11.019
SN  - 0956-5663
VL  - 126
SP  - 510
EP  - 517
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Bronder, Thomas
A1  - Jessing, Max P.
A1  - Poghossian, Arshak
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Detection of PCR-Amplified Tuberculosis DNA Fragments with Polyelectrolyte-Modified Field-Effect Sensors
JF  - Analytical Chemistry
N2  - Field-effect-based electrolyte-insulator-semiconductor (EIS) sensors were modified with a bilayer of positively charged weak polyelectrolyte (poly(allylamine hydrochloride) (PAH)) and probe single-stranded DNA (ssDNA) and are used for the detection of complementary single-stranded target DNA (cDNA) in different test solutions. The sensing mechanism is based on the detection of the intrinsic molecular charge of target cDNA molecules after the hybridization event between cDNA and immobilized probe ssDNA. The test solutions contain synthetic cDNA oligonucleotides (with a sequence of tuberculosis mycobacteria genome) or PCR-amplified DNA (which origins from a template DNA strand that has been extracted from Mycobacterium avium paratuberculosis-spiked human sputum samples), respectively. Sensor responses up to 41 mV have been measured for the test solutions with DNA, while only small signals of ∼5 mV were detected for solutions without DNA. The lower detection limit of the EIS sensors was ∼0.3 nM, and the sensitivity was ∼7.2 mV/decade. Fluorescence experiments using SybrGreen I fluorescence dye support the electrochemical results.
Y1  - 2018
U6  - https://doi.org/10.1021/acs.analchem.8b01807
SN  - 0003-2700
VL  - 90
IS  - 12
SP  - 7747
EP  - 7753
PB  - ACS Publications
CY  - Washington, DC
ER  - 
TY  - THES
A1  - Bronder, Thomas
T1  - Label-free detection of tuberculosis DNA with capacitive field-effect biosensors
Y1  - 2020
U6  - https://doi.org/10.17192/z2021.0056
N1  - Dissertation, Universität, Marburg 2020
PB  - Philipps-Universität Marburg
CY  - Marburg
ER  - 
TY  - JOUR
A1  - Breuer, Lars
A1  - Raue, Markus
A1  - Strobel, M.
A1  - Mang, Thomas
A1  - Schöning, Michael Josef
A1  - Thoelen, R.
A1  - Wagner, Torsten
T1  - Hydrogels with incorporated graphene oxide as light-addressable actuator materials for cell culture environments in lab-on-chip systems
JF  - Physica status solidi (a)
N2  - Abstractauthoren Graphene oxide (GO) nanoparticles were incorporated in temperature-sensitive Poly(N-isopropylacrylamide) (PNIPAAm) hydrogels. The nanoparticles increase the light absorption and convert light energy into heat efficiently. Thus, the hydrogels with GO can be stimulated spatially resolved by illumination as it was demonstrated by IR thermography. The temporal progression of the temperature maximum was detected for different concentrations of GO within the polymer network. Furthermore, the compatibility of PNIPAAm hydrogels with GO and cell cultures was investigated. For this purpose, culture medium was incubated with hydrogels containing GO and the viability and morphology of chinese hamster ovary (CHO) cells was examined after several days of culturing in presence of this medium.
Y1  - 2016
U6  - https://doi.org/10.1002/pssa.201533056
SN  - 1862-6300
VL  - 213
IS  - 6
SP  - 1520
EP  - 1525
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - CHAP
A1  - Breuer, Lars
A1  - Raue, Markus
A1  - Mang, Thomas
A1  - Schöning, Michael Josef
A1  - Thoelen, Ronald
A1  - Wagner, Torsten
T1  - Light-stimulated hydrogel actuators with incorporated graphene oxide for microfluidic applications
T2  - 12. Dresdner Sensor-Symposium 2015
Y1  - 2015
U6  - https://doi.org/10.5162/12dss2015/P5.8
SP  - 206
EP  - 209
ER  - 
TY  - JOUR
A1  - Breuer, Lars
A1  - Raue, Markus
A1  - Kirschbaum, M.
A1  - Mang, Thomas
A1  - Schöning, Michael Josef
A1  - Thoelen, R.
A1  - Wagner, Torsten
T1  - Light-controllable polymeric material based on temperature-sensitive hydrogels with incorporated graphene oxide
JF  - Physica status solidi (a)
N2  - Poly(N-isopropylacrylamide) (PNIPAAm) hydrogel films with incorporated graphene oxide (GO) were developed and tested as light-stimulated actuators. GO dispersions were synthesized via Hummers method and characterized toward their optical properties and photothermal energy conversion. The hydrogels were prepared by means of photopolymerization. In addition, the influence of GO within the hydrogel network on the lower critical solution temperature (LCST) was investigated by differential scanning calorimetry (DSC). The optical absorbance and the response to illumination were determined as a function of GO concentration for thin hydrogel films. A proof of principle for the stimulation with light was performed.
Y1  - 2015
U6  - https://doi.org/10.1002/pssa.201431944
SN  - 1862-6319
VL  - 212
IS  - 6
SP  - 1368
EP  - 1374
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Breuer, Lars
A1  - Pilas, Johanna
A1  - Guthmann, Eric
A1  - Schöning, Michael Josef
A1  - Thoelen, Ronald
A1  - Wagner, Torsten
T1  - Towards light-addressable flow control: responsive hydrogels with incorporated graphene oxide as laser-driven actuator structures within microfluidic channels
JF  - Sensor and Actuators B: Chemical
Y1  - 2019
U6  - https://doi.org/10.1016/j.snb.2019.02.086
SN  - 0925-4005
VL  - 288
SP  - 579
EP  - 585
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Breuer, Lars
A1  - Mang, Thomas
A1  - Schöning, Michael Josef
A1  - Thoelen, Ronald
A1  - Wagner, Torsten
T1  - Investigation of the spatial resolution of a laser-based stimulation process for light-addressable hydrogels with incorporated graphene oxide by means of IR thermography
JF  - Sensors and Actuators A: Physical
Y1  - 2017
U6  - https://doi.org/10.1016/j.sna.2017.11.031
SN  - 0924-4247
VL  - 268
SP  - 126
EP  - 132
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Bressel, A.
A1  - Schultze, J.W.
A1  - Khan, W.
A1  - Wolfaardt, G. M.
A1  - Rohns, H.-P.
A1  - Irmscher, R.
A1  - Schöning, Michael Josef
T1  - High resolution gravimetric, optical and electrochemical investigations of microbial biofilm formation in aqueous systems
JF  - Electrochimica Acta. 48 (2003), H. 20-22
Y1  - 2003
SN  - 0013-4686
SP  - 3363
EP  - 3372
ER  - 
TY  - JOUR
A1  - Brahma, Aischarya
A1  - Musio, Biagia
A1  - Ismayilova, Uliviya
A1  - Nikbin, Nikzad
A1  - Kamptmann, Sonja B.
A1  - Siegert, Petra
A1  - Jeromin, Günter Erich
A1  - Ley, Steven
A1  - Pohl, Martina
T1  - An orthogonal biocatalytic approach for the safe generation and use of HCN in a multi-step continuous preparation of chiral O-acetylcyanohydrins
JF  - Synlett
Y1  - 2015
U6  - https://doi.org/10.1055/s-0035-1560644
SN  - 0936-5214 (Print) ; 1437-2096 (e-Journal)
IS  - Publ. online 29.09.2015
PB  - Thieme
CY  - Stuttgart
ER  - 
TY  - JOUR
A1  - Borgmeier, Claudia
A1  - Bongaerts, Johannes
A1  - Meinhardt, Friedhelm
T1  - Genetic analysis of the Bacillus licheniformis degSU operon and the impact of regulatory mutations on protease production
JF  - Journal of biotechnology
N2  - Disruption experiments targeted at the Bacillus licheniformis degSU operon and GFP-reporter analysis provided evidence for promoter activity immediately upstream of degU. pMutin mediated concomitant introduction of the degU32 allele – known to cause hypersecretion in Bacillus subtilis – resulted in a marked increase in protease activity. Application of 5-fluorouracil based counterselection through establishment of a phosphoribosyltransferase deficient Δupp strain eventually facilitated the marker-free introduction of degU32 leading to further protease enhancement achieving levels as for hypersecreting wild strains in which degU was overexpressed. Surprisingly, deletion of rapG – known to interfere with DegU DNA-binding in B. subtilis – did not enhance protease production neither in the wild type nor in the degU32 strain. The combination of degU32 and Δupp counterselection in the type strain is not only equally effective as in hypersecreting wild strains with respect to protease production but furthermore facilitates genetic strain improvement aiming at biological containment and effectiveness of biotechnological processes.
KW  - Marker-free mutagenesis
KW  - Extracellular enzymes
KW  - Uracil-phosphoribosyltransferase
KW  - Hypersecretion
Y1  - 2012
U6  - https://doi.org/10.1016/j.jbiotec.2012.02.011
SN  - 1873-4863 (E-Journal); 0168-1656 (Print)
VL  - 159
IS  - 1-2
SP  - 12
EP  - 20
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Bongaerts, Johannes
A1  - Esser, Simon
A1  - Lorbach, Volker
A1  - Al-Momani, Lóay
A1  - Müller, Michael A.
A1  - Franke, Dirk
A1  - Grondal, Christoph
A1  - Kurutsch, Anja
A1  - Bujnicki, Robert
A1  - Takors, Ralf
A1  - Raeven, Leon
A1  - Wubbolts, Marcel
A1  - Bovenberg, Roel
A1  - Nieger, Martin
A1  - Schürmann, Melanie
A1  - Trachtmann, Natalie
A1  - Kozak, Stefan
A1  - Sprenger, Georg A.
A1  - Müller, Michael
T1  - Diversity-oriented production of metabolites derived from chorismate and their use in organic synthesis
JF  - Angewandte Chemie International Edition
Y1  - 2011
SN  - 1521-3773 (E-Journal); 0570-0833 (Print); 1433-7851 (Print)
VL  - Vol. 50
IS  - Iss. 34
SP  - 7781
EP  - 7786
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Bohrn, Ulrich
A1  - Stütz, Evamaria
A1  - Fleischer, Maximilian
A1  - Schöning, Michael Josef
A1  - Wagner, Patrick
T1  - Eukaryotic cell lines as a sensitive layer for direct monitoring of carbon monoxide
JF  - Physica status solidi (a) : applications and material science. 208 (2011), H. 6
Y1  - 2011
SN  - 1862-6319
SP  - 1345
EP  - 1350
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Bohrn, Ulrich
A1  - Stütz, Evamaria
A1  - Fleischer, Maximilian
A1  - Schöning, Michael Josef
A1  - Wagner, Patrick
T1  - Using a cell-based gas biosensor for investigation of adverse effects of acetone vapors in vitro
JF  - Biosensors and Bioelectronics. 40 (2013), H. 1
Y1  - 2013
SN  - 0956-5663
SP  - 393
EP  - 400
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - CHAP
A1  - Bohrn, Ulrich
A1  - Stütz, Evamaria
A1  - Fleischer, Maximilian
A1  - Schöning, Michael Josef
A1  - Wagner, Patrick
T1  - Living cell-based gas sensor system for the detection of acetone in air
Y1  - 2012
SN  - 978-3-9813484-2-2
U6  - https://doi.org/10.5162/IMCS2012/3.2.3
SP  - 269
EP  - 272
ER  - 
TY  - JOUR
A1  - Bohrn, Ulrich
A1  - Stütz, Evamaria
A1  - Fleischer, Maximilian
A1  - Schöning, Michael Josef
T1  - Real-time detection of CO by eukaryotic cells
JF  - Procedia Engineering
N2  - In this contribution, we focus on the detection of toxic gases with living eukaryotic cells. A cell-based gas sensor system, able to measure the effects of direct exposure of gases to cells in real-time, was set up. Impedance data as well as oxygen consumption of Chinese hamster lung fibroblast cells (V79) were analysed upon exposure to carbon monoxide (CO). The CO (diluted in wet synthetic air) affects the cell respiration as indicated by an attenuated respiration signal after the CO exposure as well as an instant increase of the capacitive part of the impedance signal during the gas exposure.
Y1  - 2010
SN  - 1877-7058
N1  - Eurosensor XXIV Conference, 5-8 September 2010, Linz, Austria
VL  - 5
SP  - 17
EP  - 20
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Bohrn, Ulrich
A1  - Mucha, Andreas
A1  - Werner, Frederik
A1  - Trattner, Barbara
A1  - Bäcker, Matthias
A1  - Krumbe, Christoph
A1  - Schienle, Meinrad
A1  - Stütz, Evamaria
A1  - Schmitt-Landsiedel, Doris
A1  - Fleischer, Maximilian
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - A critical comparison of cell-based sensor systems for the detection of Cr (VI) in aquatic environment
JF  - Sensors and actuators. B: Chemical
Y1  - 2013
SN  - 1873-3077 (E-Journal); 0925-4005 (Print)
VL  - Vol. 182
SP  - 58
EP  - 65
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - CHAP
A1  - Bohrn, Ulrich
A1  - Mucha, Andreas
A1  - Werner, Frederik
A1  - Stütz, Evamaria
A1  - Bäcker, Matthias
A1  - Krumbe, Christoph
A1  - Schienle, Meinrad
A1  - Fleischer, Maximilian
A1  - Wagner, Patrick
A1  - Schöning, Michael Josef
T1  - Detection of toxic chromium species in water using cellbased sensor systems
Y1  - 2012
SN  - 978-3-9813484-2-2
U6  - https://doi.org/10.5162/IMCS2012/P2.1.14
SP  - 1364
EP  - 1367
ER  - 
TY  - JOUR
A1  - Bertz, Morten
A1  - Schöning, Michael Josef
A1  - Molinnus, Denise
A1  - Homma, Takayuki
T1  - Influence of temperature, light, and H₂O₂ concentration on microbial spore inactivation: in-situ Raman spectroscopy combined with optical trapping
JF  - Physica status solidi (a) applications and materials science
N2  - To gain insight on chemical sterilization processes, the influence of temperature (up to 70 °C), intense green light, and hydrogen peroxide (H₂O₂) concentration (up to 30% in aqueous solution) on microbial spore inactivation is evaluated by in-situ Raman spectroscopy with an optical trap. Bacillus atrophaeus is utilized as a model organism. Individual spores are isolated and their chemical makeup is monitored under dynamically changing conditions (temperature, light, and H₂O₂ concentration) to mimic industrially relevant process parameters for sterilization in the field of aseptic food processing. While isolated spores in water are highly stable, even at elevated temperatures of 70 °C, exposure to H₂O₂ leads to a loss of spore integrity characterized by the release of the key spore biomarker dipicolinic acid (DPA) in a concentration-dependent manner, which indicates damage to the inner membrane of the spore. Intensive light or heat, both of which accelerate the decomposition of H₂O₂ into reactive oxygen species (ROS), drastically shorten the spore lifetime, suggesting the formation of ROS as a rate-limiting step during sterilization. It is concluded that Raman spectroscopy can deliver mechanistic insight into the mode of action of H₂O₂-based sterilization and reveal the individual contributions of different sterilization methods acting in tandem.
KW  - hydrogen peroxide
KW  - optical spore trapping
KW  - Raman spectroscopy
KW  - sterilization conditions
KW  - temperature
Y1  - 2024
U6  - https://doi.org/10.1002/pssa.202300866
SN  - 1862-6319 (Online)
SN  - 1862-6300 (Print)
N1  - Corresponding author: Michael J. Schöning
IS  - Early View
PB  - Wiley-VCH
CY  - Berlin
ER  -