TY  - JOUR
A1  - Vahidpour, Farnoosh
A1  - Guthman, Eric
A1  - Arreola, Julia
A1  - Alghazali, Yousef H. M.
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
T1  - Assessment of Various Process Parameters for Optimized Sterilization Conditions Using a Multi-Sensing Platform
JF  - Foods
N2  - In this study, an online multi-sensing platform was engineered to simultaneously evaluate various process parameters of food package sterilization using gaseous hydrogen peroxide (H₂O₂). The platform enabled the validation of critical aseptic parameters. In parallel, one series of microbiological count reduction tests was performed using highly resistant spores of B. atrophaeus DSM 675 to act as the reference method for sterility validation. By means of the multi-sensing platform together with microbiological tests, we examined sterilization process parameters to define the most effective conditions with regards to the highest spore kill rate necessary for aseptic packaging. As these parameters are mutually associated, a correlation between different factors was elaborated. The resulting correlation indicated the need for specific conditions regarding the applied H₂O₂ gas temperature, the gas flow and concentration, the relative humidity and the exposure time. Finally, the novel multi-sensing platform together with the mobile electronic readout setup allowed for the online and on-site monitoring of the sterilization process, selecting the best conditions for sterility and, at the same time, reducing the use of the time-consuming and costly microbiological tests that are currently used in the food package industry.
KW  - spore kill rate
KW  - sterility
KW  - aseptic parameters
KW  - multi-sensing platform
KW  - gaseous hydrogen peroxide
Y1  - 2022
U6  - http://dx.doi.org/10.3390/foods11050660
SN  - 2304-8158
N1  - This article belongs to the Special Issue "Sensors and Biosensors Application for Food Industries"
VL  - 11
IS  - 5
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Vahidpour, Farnoosh
A1  - Alghazali, Yousef
A1  - Akca, Sevilay
A1  - Hommes, Gregor
A1  - Schöning, Michael Josef
T1  - An Enzyme-Based Interdigitated Electrode-Type Biosensor for Detecting Low Concentrations of H₂O₂ Vapor/Aerosol
JF  - Chemosensors
N2  - This work introduces a novel method for the detection of H₂O₂ vapor/aerosol of low concentrations, which is mainly applied in the sterilization of equipment in medical industry. Interdigitated electrode (IDE) structures have been fabricated by means of microfabrication techniques. A differential setup of IDEs was prepared, containing an active sensor element (active IDE) and a passive sensor element (passive IDE), where the former was immobilized with an enzymatic membrane of horseradish peroxidase that is selective towards H₂O₂. Changes in the IDEs’ capacitance values (active sensor element versus passive sensor element) under H₂O₂ vapor/aerosol atmosphere proved the detection in the concentration range up to 630 ppm with a fast response time (<60 s). The influence of relative humidity was also tested with regard to the sensor signal, showing no cross-sensitivity. The repeatability assessment of the IDE biosensors confirmed their stable capacitive signal in eight subsequent cycles of exposure to H₂O₂ vapor/aerosol. Room-temperature detection of H₂O₂ vapor/aerosol with such miniaturized biosensors will allow a future three-dimensional, flexible mapping of aseptic chambers and help to evaluate sterilization assurance in medical industry.
Y1  - 2022
U6  - http://dx.doi.org/10.3390/chemosensors10060202
SN  - 2227-9040
N1  - This article belongs to the Special Issue "Bioinspired Chemical Sensors and Micro-Nano Devices"
VL  - 10
IS  - 6
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Turek, Monika
A1  - Ketterer, Lothar
A1  - Claßen, Melanie
A1  - Berndt, Heinz
A1  - Elbers, Gereon
A1  - Krüger, Peter
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Development and Electrochemical Investigations of an EIS-(Electrolyte-Insulator-Semiconductor) based Biosensor for Cyanide Detection
JF  - Sensors
Y1  - 2007
SN  - 1424-8220
VL  - 7
IS  - 8
SP  - 1415
EP  - 1426
ER  - 
TY  - JOUR
A1  - Turek, Monik
A1  - Heiden, Wolfgang
A1  - Guo, Sharon
A1  - Riesen, Alfred
A1  - Schubert, Jürgen
A1  - Zander, Willi
A1  - Krüger, Peter
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Simultaneous detection of cyanide and heavy metals for environmental analysis by means of µISEs
JF  - Physica Status Solidi (A). 207 (2010), H. 4
Y1  - 2010
SN  - 1862-6300
N1  - Special Issue: Engineering of Functional Interfaces EnFI 2009
SP  - 817
EP  - 823
ER  - 
TY  - JOUR
A1  - Turek, M.
A1  - Keusgen, M.
A1  - Poghossian, Arshak
A1  - Mulchandani, A.
A1  - Wang, J.
A1  - Schöning, Michael Josef
T1  - Enzyme-modified electrolyte-insulator-semiconductor sensors
JF  - Journal of Contemporary Physics. 43 (2008), H. 2
Y1  - 2008
SN  - 1934-9378
N1  - Armenian Academy of Sciences
SP  - 82
EP  - 85
ER  - 
TY  - JOUR
A1  - Tillmann, K.
A1  - Förster, Arnold
T1  - Critical dimensions for the formation of interfacial misfit dislocations of In0.6Ga0.4As islands on GaAs(001)
JF  - Thin Solid Films. 368 (2000), H. 1
Y1  - 2000
SN  - 0040-6090
SP  - 93
EP  - 104
ER  - 
TY  - JOUR
A1  - Takenaga, Shoko
A1  - Schneider, Benno
A1  - Erbay, E.
A1  - Biselli, Manfred
A1  - Schnitzler, Thomas
A1  - Schöning, Michael Josef
A1  - Wagner, Torsten
T1  - Fabrication of biocompatible lab-on-chip devices for biomedical applications by means of a 3D-printing process
JF  - Physica status solidi (a)
N2  - A new microfluidic assembly method for semiconductor-based biosensors using 3D-printing technologies was proposed for a rapid and cost-efficient design of new sensor systems. The microfluidic unit is designed and printed by a 3D-printer in just a few hours and assembled on a light-addressable potentiometric sensor (LAPS) chip using a photo resin. The cell growth curves obtained from culturing cells within microfluidics-based LAPS systems were compared with cell growth curves in cell culture flasks to examine biocompatibility of the 3D-printed chips. Furthermore, an optimal cell culturing within microfluidics-based LAPS chips was achieved by adjusting the fetal calf serum concentrations of the cell culture medium, an important factor for the cell proliferation.
Y1  - 2015
U6  - http://dx.doi.org/10.1002/pssa.201532053
SN  - 1862-6319
VL  - 212
IS  - 6
SP  - 1347
EP  - 1352
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Takenaga, Shoko
A1  - Biselli, Manfred
A1  - Schnitzler, Thomas
A1  - Öhlschläger, Peter
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
T1  - Toward multi-analyte bioarray sensors: LAPS-based on-chip determination of a Michaelis–Menten-like kinetics for cell culturing
JF  - Physica status solidi A : Applications and materials science
N2  - The metabolic activity of Chinese hamster ovary (CHO) cells was observed using a light-addressable potentiometric sensor (LAPS). The dependency toward different glucose concentrations (17–200 mM) follows a Michaelis–Menten kinetics trajectory with Kₘ = 32.8 mM, and the obtained Kₘ value in this experiment was compared with that found in literature. In addition, the pH shift induced by glucose metabolism of tumor cells transfected with the HPV-16 genome (C3 cells) was successfully observed. These results indicate the possibility to determine the tumor cells metabolism with a LAPS-based measurement device.
Y1  - 2014
U6  - http://dx.doi.org/10.1002/pssa.201330464
SN  - 1521-396X (E); 1862-6319 (E-Journal); 0031-8965 (Print); 1862-6300 (Print)
VL  - 211
IS  - 6
SP  - 1410
EP  - 1415
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Stock, J.
A1  - Malindretos, J.
A1  - Indlekofer, K.M.
A1  - Pöttgens, Michael
A1  - Förster, Arnold
A1  - Lüth, Hans
T1  - A Vertical Resonant Tunneling Transistor for Application in Digital Logic Circuits
JF  - IEEE Transactions on Electron Devices (T-ED). 48 (2001), H. 6
Y1  - 2001
SN  - 0018-9383
SP  - 1028
EP  - 1032
ER  - 
TY  - JOUR
A1  - Srnanek, R.
A1  - Geurts, J.
A1  - Lentze, M.
A1  - Irmer, G.
A1  - Donoval, D.
A1  - Brdecka, P.
A1  - Kordos, P.
A1  - Förster, Arnold
A1  - Sciana, B.
A1  - Radziewicz, D.
A1  - Tlaczala, M.
T1  - Study of d-doped GaAs layers by micro-Raman spectroscopy on bevelled samples
JF  - Applied surface science  . 230 (2004), H. 1 -4
Y1  - 2004
SN  - 0169-4332
N1  - ISSN der E-Ausg.: 0169-4332
SP  - 379
EP  - 385
ER  -