TY  - JOUR
A1  - Oberländer, Jan
A1  - Bromm, Alexander
A1  - Wendeler, Luisa
A1  - Iken, Heiko
A1  - Palomar Duran, Marlena
A1  - Greeff, Anton
A1  - Kirchner, Patrick
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Towards a biosensor to monitor the sterilisation efficiency of aseptic filling machines
JF  - Physica status solidi (a)
N2  - Sterilisation processes are compulsory in medicine, pharmacy, and food industries to prevent infections of consumers and microbiological contaminations of products. Monitoring the sterilisation by conventional microbiological methods is time- and lab-consuming. To overcome this problem, in this work a novel biosensor has been proposed. The sensor enables a fast method to evaluate sterilisation processes. By means of thin-film technology the sensor's transducer structures in form of IDEs (interdigitated electrodes) have been fabricated on a silicon substrate. Physical characterisation of the developed sensor was done by AFM, SEM, and profilometry. Impedance analyses were conducted for the electrical characterisation. As microbiological layer spores of B. atrophaeus have been immobilised on the sensing structure; spores of this type are a well-known sterilisation test organism. Impedance measurements at a fixed frequency over time were performed to monitor the immobilisation process. A sterilisation process according to aseptic filling machines was applied to demonstrate the sensor functionality. After both, immobilisation and sterilisation, a change in impedance could successfully be detected.
Y1  - 2015
U6  - http://dx.doi.org/10.1002/pssa.201431900
SN  - 1862-6319
VL  - 212
IS  - 6
SP  - 1299
EP  - 1305
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Oberländer, Jan
A1  - Jildeh, Zaid B.
A1  - Kirchner, Patrick
A1  - Wendeler, Luisa
A1  - Bromm, Alexander
A1  - Iken, Heiko
A1  - Wagner, Patrick
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Study of Interdigitated Electrode Arrays Using Experiments and Finite Element Models for the Evaluation of Sterilization Processes
JF  - Sensors
N2  - In this work, a sensor to evaluate sterilization processes with hydrogen peroxide vapor has been characterized. Experimental, analytical and numerical methods were applied to evaluate and study the sensor behavior. The sensor set-up is based on planar interdigitated electrodes. The interdigitated electrode structure consists of 614 electrode fingers spanning over a total sensing area of 20 mm2. Sensor measurements were conducted with and without microbiological spores as well as after an industrial sterilization protocol. The measurements were verified using an analytical expression based on a first-order elliptical integral. A model based on the finite element method with periodic boundary conditions in two dimensions was developed and utilized to validate the experimental findings.
Y1  - 2015
U6  - http://dx.doi.org/10.3390/s151026115
SN  - 1424-8220
N1  - This article belongs to the Special Issue "Gas Sensors—Designs and Applications"
VL  - 15
IS  - 10
SP  - 26115
EP  - 26127
PB  - MDPI
CY  - Basel
ER  - 
TY  - CHAP
A1  - Oberländer, Jan
A1  - Jildeh, Zaid B.
A1  - Kirchner, Patrick
A1  - Wendeler, Luisa
A1  - Bromm, Alexander
A1  - Iken, Heiko
A1  - Wagner, Patrick
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Experimental and numerical evaluation of interdigitated electrode array for monitoring gaseous sterilization processes
T2  - 12. Dresdner Sensor-Symposium 2015
Y1  - 2015
U6  - http://dx.doi.org/10.5162/12dss2015/P3.11
SP  - 163
EP  - 168
ER  - 
TY  - JOUR
A1  - Oberländer, Jan
A1  - Kirchner, Patrick
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Strategies in developing thin-film sensors for monitoring aseptic food processes : Theoretical considerations and investigations of passivation materials
JF  - Electrochimica Acta
N2  - The sterilization of packages in aseptic food processes is highly significant to maintain a consumer-safe product with extended shelf-life. Today, the sterilization of food packages is predominantly accomplished by gaseous hydrogen peroxide (H2O2) in combination with heat. In order to monitor this sterilization process, calorimetric gas sensors as differential set-up of two platinum temperature sensors representing a catalytically active (additionally deposition of MnO2) and a passive segment have been recently developed. The temperature rise of the exothermic decomposition serves as an indicator of the present H2O2 concentration. In the present work, a theoretical approach considering the sensor’s thermochemistry and physical transport phenomena was formulated to evaluate the temperature rise based on the energy content of gaseous H2O2. In a further part of this work, three polymers have been analyzed with respect to their application as passivation materials. The examined polymers are photoresist SU-8, perfluoroalkoxy (PFA) and fluorinated ethylene propylene (FEP). Thermal analyses by means of differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) have been conducted to determine the operation limits of the polymers. The overall chemical resistance and stability of the polymers against the harsh environmental conditions during the sterilization process have been examined by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR).
Y1  - 2015
U6  - http://dx.doi.org/10.1016/j.electacta.2015.06.126
SN  - 0013-4686
VL  - 183
SP  - 130
EP  - 136
PB  - Elsevier
CY  - Amsterdam
ER  -