TY  - JOUR
A1  - Poghossian, Arshak
A1  - Bäcker, Matthias
A1  - Mayer, Dirk
A1  - Schöning, Michael Josef
T1  - Gating capacitive field-effect sensors by the charge of nanoparticle/molecule hybrids
JF  - Nanoscale
Y1  - 2015
U6  - http://dx.doi.org/10.1039/C4NR05987E
SN  - 2040-3372 (E-Journal); 2040-3364 (Print)
SP  - 1023
EP  - 1031
PB  - Royal Society of Chemistry (RSC)
CY  - Cambridge
ER  - 
TY  - JOUR
A1  - Mikulics, M.
A1  - Camara, I.
A1  - Hardt, A. van der
A1  - Fox, A.
A1  - Förster, Arnold
A1  - Gusten, R.
A1  - Lüth, H.
A1  - Kordos, P.
T1  - Generation of THz radiation by photomixing in low-temperature-grown MBE GaAs
JF  - Fifth International Conference on Advanced Semiconductor Devices and Microsystems : conference proceedings ; Smolenice Castle, Slovakia, October 17 - 21, 2004 / [organizers: Institute of Electrical Engineering, Slovak Academy of Sciences, Bratislava and Microelectronics Department, Faculty of Electrical Engineering and Information Technology, Slovak University of Technology, Bratislava]. Ed. by J. Osvald
Y1  - 2004
SN  - 0-7803-8335-7
N1  - International Conference on Advanced Semiconductor Devices and Microsystems <5, 2004, Smolenice> ; ASDAM <5, 2004, Smolenice> ; IEEE catalog numer: 04EX867
SP  - 231
EP  - 234
PB  - IEEE Operations Center
CY  - Piscataway, NJ
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  - http://dx.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  - Deppe, Veronika Maria
A1  - Klatte, Stephanie
A1  - Bongaerts, Johannes
A1  - Maurer, Karl-Heinz
A1  - O'Connell, Timothy
A1  - Meinhardt, Friedhelm
T1  - Genetic control of Amadori product degradation in Bacillus subtilis via regulation of frlBONMD expression by FrlR
JF  - Applied and environmental microbiology
Y1  - 2011
SN  - 1098-5336 (E-Journal); 0003-6919 (Print); 0099-2240 (Print)
VL  - Vol. 77
IS  - No. 9
SP  - 2839
EP  - 2846
PB  - American Society of Mechanical Engineers (ASME)
CY  - New York
ER  - 
TY  - JOUR
A1  - Karschuck, Tobias
A1  - Kaulen, Corinna
A1  - Poghossian, Arshak
A1  - Wagner, Patrick H.
A1  - Schöning, Michael Josef
T1  - Gold nanoparticle-modified capacitive field-effect sensors: Studying the surface density of nanoparticles and coupling of charged polyelectrolyte macromolecules
JF  - Electrochemical Science Advances
N2  - The coupling of ligand-stabilized gold nanoparticles with field-effect devices offers new possibilities for label-free biosensing. In this work, we study the immobilization of aminooctanethiol-stabilized gold nanoparticles (AuAOTs) on the silicon dioxide surface of a capacitive field-effect sensor. The terminal amino group of the AuAOT is well suited for the functionalization with biomolecules. The attachment of the positively-charged AuAOTs on a capacitive field-effect sensor was detected by direct electrical readout using capacitance-voltage and constant capacitance measurements. With a higher particle density on the sensor surface, the measured signal change was correspondingly more pronounced. The results demonstrate the ability of capacitive field-effect sensors for the non-destructive quantitative validation of nanoparticle immobilization. In addition, the electrostatic binding of the polyanion polystyrene sulfonate to the AuAOT-modified sensor surface was studied as a model system for the label-free detection of charged macromolecules. Most likely, this approach can be transferred to the label-free detection of other charged molecules such as enzymes or antibodies.
KW  - polystyrene sulfonate
KW  - gold nanoparticles
KW  - field-effect sensor
KW  - detection of charged macromolecules
KW  - capacitive EIS sensor
Y1  - 2021
U6  - http://dx.doi.org/10.1002/elsa.202100179
SN  - 0938-5193
VL  - 2
IS  - 5
PB  - Wiley-VCH
CY  - Weinheim
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  - 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  - Murib, M. S.
A1  - Yeap, W. S.
A1  - Eurlings, Y.
A1  - Grinsven, B. van
A1  - Boyen, H.-G.
A1  - Conings, B.
A1  - Michiels, L.
A1  - Ameloot, M.
A1  - Carleer, R.
A1  - Warmer, J.
A1  - Kaul, P.
A1  - Haenen, K.
A1  - Schöning, Michael Josef
A1  - Ceuninck, W. de
A1  - Wagner, P.
T1  - Heat-transfer based characterization of DNA on synthetic sapphire chips
JF  - Sensors and Actuators B: Chemical
N2  - In this study, we show that synthetic sapphire (Al₂O₃), an established implant material, can also serve as a platform material for biosensors comparable to nanocrystalline diamond. Sapphire chips, beads, and powder were first modified with (3-aminopropyl) triethoxysilane (APTES), followed by succinic anhydride (SA), and finally single-stranded probe DNA was EDC coupled to the functionalized layer. The presence of the APTES-SA layer on sapphire powders was confirmed by thermogravimetric analyis and Fourier-transform infrared spectroscopy. Using planar sapphire chips as substrates and X-ray photoelectron spectroscopy (XPS) as surface-sensitive tool, the sequence of individual layers was analyzed with respect to their chemical state, enabling the quantification of areal densities of the involved molecular units. Fluorescence microscopy was used to demonstrate the hybridization of fluorescently tagged target DNA to the probe DNA, including denaturation- and re-hybridization experiments. Due to its high thermal conductivity, synthetic sapphire is especially suitable as a chip material for the heat-transfer method, which was employed to distinguish complementary- and non-complementary DNA duplexes containing single-nucleotide polymorphisms. These results indicate that it is possible to detect mutations electronically with a chemically resilient and electrically insulating chip material.
Y1  - 2016
U6  - http://dx.doi.org/10.1016/j.snb.2016.02.027
SN  - 0925-4005
VL  - 230
IS  - 230
SP  - 260
EP  - 271
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Grinsven, Bart van
A1  - Bon, Natalie vanden
A1  - Strauven, Hannelore
A1  - Grieten, Lars
A1  - Murib, Mohammed
A1  - Jiménez Monroy, Kathia L.
A1  - Janssens, Stoffel D.
A1  - Haenen, Ken
A1  - Schöning, Michael Josef
A1  - Vermeeren, Veronique
A1  - Ameloot, Marcel
A1  - Michiels, Luc
A1  - Thoelen, Ronald
A1  - Ceuninck, Ward de
A1  - Wagner, Patrick
T1  - Heat-Transfer Resistance at Solid-Liquid Interfaces: A Tool for The Detection of Single Nucleotide Polymorphisms in DNA.
JF  - ACS Nano
N2  - In this article, we report on the heat-transfer resistance at interfaces as a novel, denaturation-based method to detect single-nucleotide polymorphisms in DNA. We observed that a molecular brush of double-stranded DNA grafted onto synthetic diamond surfaces does not notably affect the heat-transfer resistance at the solid-to-liquid interface. In contrast to this, molecular brushes of single-stranded DNA cause, surprisingly, a substantially higher heat-transfer resistance and behave like a thermally insulating layer. This effect can be utilized to identify ds-DNA melting temperatures via the switching from low- to high heat-transfer resistance. The melting temperatures identified with this method for different DNA duplexes (29 base pairs without and with built-in mutations) correlate nicely with data calculated by modeling. The method is fast, label-free (without the need for fluorescent or radioactive markers), allows for repetitive measurements, and can also be extended toward array formats. Reference measurements by confocal fluorescence microscopy and impedance spectroscopy confirm that the switching of heat-transfer resistance upon denaturation is indeed related to the thermal on-chip denaturation of DNA.
Y1  - 2012
U6  - http://dx.doi.org/10.1021/nn300147e
SN  - 1936-086X
VL  - 6
IS  - 3
SP  - 2712
EP  - 2721
PB  - ACS Publications
CY  - Washington, DC
ER  - 
TY  - CHAP
A1  - Kloock, Joachim P.
A1  - Schöning, Michael Josef
T1  - Heavy metal detection with semiconductor devices based on PLD-prepared chalcogenide glass thin films
T2  - Armenian Journal of Physics
Y1  - 2007
SN  - 1829-1171
SP  - 95
EP  - 98
ER  - 
TY  - JOUR
A1  - Heine, A.
A1  - Herrmann, G.
A1  - Selmer, Thorsten
A1  - Terwesten, F.
A1  - Buckel, W.
A1  - Reuter, K.
T1  - High resolution crystal structure of clostridium propionicum β-Alanyl-CoA:Ammonia Lyase, a new member of the "Hot Dog Fold" protein superfamily
JF  - Proteins
N2  - Clostridium propionicum is the only organism known to ferment β-alanine, a constituent of coenzyme A (CoA) and the phosphopantetheinyl prosthetic group of holo-acyl carrier protein. The first step in the fermentation is a CoA-transfer to β-alanine. Subsequently, the resulting β-alanyl-CoA is deaminated by the enzyme β-alanyl-CoA:ammonia lyase (Acl) to reversibly form ammonia and acrylyl-CoA. We have determined the crystal structure of Acl in its apo-form at a resolution of 0.97 Å as well as in complex with CoA at a resolution of 1.59 Å. The structures reveal that the enyzme belongs to a superfamily of proteins exhibiting a so called “hot dog fold” which is characterized by a five-stranded antiparallel β-sheet with a long α-helix packed against it. The functional unit of all “hot dog fold” proteins is a homodimer containing two equivalent substrate binding sites which are established by the dimer interface. In the case of Acl, three functional dimers combine to a homohexamer strongly resembling the homohexamer formed by YciA-like acyl-CoA thioesterases. Here, we propose an enzymatic mechanism based on the crystal structure of the Acl·CoA complex and molecular docking. Proteins 2014; 82:2041–2053. © 2014 Wiley Periodicals, Inc.
Y1  - 2014
U6  - http://dx.doi.org/10.1002/prot.24557
SN  - 1097-0134 (E-Journal); 0887-3585 (Print)
VL  - 82
IS  - 9
SP  - 2041
EP  - 2053
PB  - Wiley-Liss
CY  - New York
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  - Moritz, W.
A1  - Yoshinobu, T.
A1  - Finger, F.
A1  - Krause, S.
A1  - Martin-Fernandez, M.
A1  - Schöning, Michael Josef
T1  - High resolution LAPS using amorphous silicon as the semiconductor material
JF  - Sensors and Actuators B. 103 (2004), H. 1-2
Y1  - 2004
SN  - 0925-4005
SP  - 436
EP  - 444
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  - 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  - Procedia Engineering. 25 (2011)
Y1  - 2011
SN  - 1877-7058
N1  - EurosensorsXXV ; Proc. Eurosensors XXV, September 4-7, 2011, Athens, Greece
SP  - 346
EP  - 349
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Voigt, Birgit
A1  - Albrecht, Dirk
A1  - Sievers, Susanne
A1  - Becher, Dörte
A1  - Bongaerts, Johannes
A1  - Evers, Stefan
A1  - Schweder, Thomas
A1  - Maurer, Karl-Heinz
A1  - Hecker, Michael
T1  - High-resolution proteome maps of Bacillus licheniformis cells growing in minimal medium
JF  - Proteomics
Y1  - 2015
U6  - http://dx.doi.org/10.1002/pmic.201400504
SN  - 1615-9861
VL  - 15
IS  - 15
SP  - 2629
EP  - 2633
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Miyamoto, Ko-ichiro
A1  - Itabashi, Akinori
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
A1  - Yoshinobu, Tatsuo
T1  - High-speed chemical imaging inside a microfluidic channel
JF  - Sensors and actuators. B: Chemical
N2  - In this study, a high-speed chemical imaging system was developed for visualization of the interior of a microfluidic channel. A microfluidic channel was constructed on the sensor surface of the light-addressable potentiometric sensor (LAPS), on which the ion concentrations could be measured in parallel at up to 64 points illuminated by optical fibers. The temporal change of pH distribution inside the microfluidic channel was recorded at a maximum rate of 100 frames per second (fps). The high frame rate allowed visualization of moving interfaces and plugs in the channel even at a flow velocity of 111 mm/s, which suggests the feasibility of plug-based microfluidic devices for flow-injection analysis (FIA).
Y1  - 2014
U6  - http://dx.doi.org/10.1016/j.snb.2013.12.090
SN  - 1873-3077 (E-Journal); 0925-4005 (Print)
VL  - 194
SP  - 521
EP  - 527
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Itabashi, Akinori
A1  - Kosaka, Naoki
A1  - Miyamoto, Ko-ichiro
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
T1  - High-speed chemical imaging system based on front-side-illuminated LAPS
JF  - Sensors and actuators B: Chemical
N2  - The chemical imaging sensor is a semiconductor-based chemical sensor that can visualize the spatial distribution of specific ions on the sensing surface. The conventional chemical imaging system based on the light-addressable potentiometric sensor (LAPS), however, required a long time to obtain a chemical image, due to the slow mechanical scan of a single light beam. For high-speed imaging, a plurality of light beams modulated at different frequencies can be employed to measure the ion concentrations simultaneously at different locations on the sensor plate by frequency division multiplex (FDM). However, the conventional measurement geometry of back-side illumination limited the bandwidth of the modulation frequency required for FDM measurement, because of the low-pass filtering characteristics of carrier diffusion in the Si substrate. In this study, a high-speed chemical imaging system based on front-side-illuminated LAPS was developed, which achieved high-speed spatiotemporal recording of pH change at a rate of 70 frames per second.
Y1  - 2013
U6  - http://dx.doi.org/10.1016/j.snb.2013.03.016
SN  - 1873-3077
VL  - 182
SP  - 315
EP  - 321
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Hoskens, R.C.P.
A1  - Roer, T.G. van de
A1  - Tolstikhin, V.I.
A1  - Förster, Arnold
T1  - Hot electron injection laser: vertically integrated transistor-laser structure for high-speed, low-chirp direct modulation
JF  - LEOS 2000 : 2000 IEEE annual meeting conference proceedings; 13th annual meeting; IEEE Lasers and Electro-Optics Society 2000 annual meeting; 13-16 November 2000, The Westin Rio Mar Beach, Rio Grande, Puerto Rico. Vol. 2
Y1  - 2000
SN  - 0-7803-5947-X
N1  - 2000 IEEE LEOS annual meeting
SP  - 444
EP  - 445
PB  - IEEE Service Center
CY  - Piscataway, NJ
ER  - 
TY  - JOUR
A1  - Förster, Arnold
A1  - Lepsa, M. I.
A1  - Freundt, D.
T1  - Hot electron injector Gunn diode for advanced driver assistance systems
JF  - Applied physics A: materials science and processing. 87 (2007), H. 3
Y1  - 2007
SN  - 0947-8396
N1  - ISSN der E-Ausg.: 1432-0630 ; Special issue
SP  - 545
EP  - 558
ER  -