TY  - JOUR
A1  - Reisert, Steffen
A1  - Geissler, H.
A1  - Weiler, C.
A1  - Wagner, P.
A1  - Schöning, Michael Josef
T1  - Multiple sensor-type system for monitoring the microbicidal effectiveness of aseptic sterilisation processes
JF  - Food control
N2  - The present work describes a novel multiple sensor-type system for the real-time analysis of aseptic sterilisation processes employing gaseous hydrogen peroxide (H2O2) as a sterilant. The inactivation kinetics of Bacillus atrophaeus by gaseous H2O2 have been investigated by means of a methodical calibration experiment, taking into account the process variables H2O2 concentration, humidity and gas temperature. It has been found that the microbicidal effectiveness at H2O2 concentrations above 2% v/v is largely determined by the concentration itself, while at lower H2O2 concentrations, the gas temperature and humidity play a leading role. Furthermore, the responses of different types of gas sensors towards the influencing factors of the sterilisation process have been analysed within the same experiment. Based on a correlation established between the inactivation kinetics and the sensor responses, a calorimetric H2O2 sensor and a metal-oxide semiconductor (MOX) sensor have been identified as possible candidates for monitoring the microbicidal effectiveness of aseptic sterilisation processes employing gaseous H2O2. Therefore, two linear models that describe the relationship between sensor response and microbicidal effectiveness have been proposed.
Y1  - 2015
U6  - http://dx.doi.org/10.1016/j.foodcont.2014.07.063
SN  - 1873-7129 (E-Journal); 0956-7135 (Print)
VL  - 47
SP  - 615
EP  - 622
ER  - 
TY  - JOUR
A1  - Schusser, Sebastian
A1  - Poghossian, Arshak
A1  - Bäcker, Matthias
A1  - Krischer, M.
A1  - Leinhos, Marcel
A1  - Wagner, P.
A1  - Schöning, Michael Josef
T1  - An application of field-effect sensors for in-situ monitoring of degradation of biopolymers
JF  - Sensors and actuators B: Chemical
N2  - 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).
Y1  - 2015
U6  - http://dx.doi.org/10.1016/j.snb.2014.10.058
SN  - 1873-3077 (E-Journal); 0925-4005 (Print)
VL  - 207, Part B
SP  - 954
EP  - 959
PB  - Elsevier
CY  - Amsterdam
ER  - 
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  - http://dx.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  -