@article{AbouzarPoghossianRazavietal.2008, author = {Abouzar, Maryam H. and Poghossian, Arshak and Razavi, Arash and Besmehn, Astrid and Bijnens, Nathalie and Williams, Oliver A. and Haenen, Ken and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Penicillin detection with nanocrystalline-diamond field-effect sensor}, series = {physica status solidi (a). 205 (2008), H. 9}, journal = {physica status solidi (a). 205 (2008), H. 9}, isbn = {1862-6319}, pages = {2141 -- 2145}, year = {2008}, language = {en} } @article{KarschuckKaulenPoghossianetal.2021, author = {Karschuck, Tobias and Kaulen, Corinna and Poghossian, Arshak and Wagner, Patrick H. and Sch{\"o}ning, Michael Josef}, title = {Gold nanoparticle-modified capacitive field-effect sensors: Studying the surface density of nanoparticles and coupling of charged polyelectrolyte macromolecules}, series = {Electrochemical Science Advances}, volume = {2}, journal = {Electrochemical Science Advances}, number = {5}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0938-5193}, doi = {10.1002/elsa.202100179}, pages = {10 Seiten}, year = {2021}, abstract = {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.}, language = {en} } @article{VahidpourGuthmanArreolaetal.2022, author = {Vahidpour, Farnoosh and Guthman, Eric and Arreola, Julia and Alghazali, Yousef H. M. and Wagner, Torsten and Sch{\"o}ning, Michael Josef}, title = {Assessment of Various Process Parameters for Optimized Sterilization Conditions Using a Multi-Sensing Platform}, series = {Foods}, volume = {11}, journal = {Foods}, number = {5}, publisher = {MDPI}, address = {Basel}, issn = {2304-8158}, doi = {10.3390/foods11050660}, pages = {Artikel 660}, year = {2022}, abstract = {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.}, language = {en} } @article{JildehOberlaenderKirchneretal.2018, author = {Jildeh, Zaid B. and Oberl{\"a}nder, Jan and Kirchner, Patrick and Keusgen, Michael and Wagner, Patrick H. and Sch{\"o}ning, Michael Josef}, title = {Experimental and Numerical Analyzes of a Sensor Based on Interdigitated Electrodes for Studying Microbiological Alterations}, series = {physica status solidi (a): applications and materials science}, volume = {215}, journal = {physica status solidi (a): applications and materials science}, number = {15}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.201700920}, pages = {Artikel 1700920}, year = {2018}, abstract = {In this work, a cell-based biosensor to evaluate the sterilization efficacy of hydrogen peroxide vapor sterilization processes is characterized. The transducer of the biosensor is based on interdigitated gold electrodes fabricated on an inert glass substrate. Impedance spectroscopy is applied to evaluate the sensor behavior and the alteration of test microorganisms due to the sterilization process. These alterations are related to changes in relative permittivity and electrical conductivity of the bacterial spores. Sensor measurements are conducted with and without bacterial spores (Bacillus atrophaeus), as well as after an industrial sterilization protocol. Equivalent two-dimensional numerical models based on finite element method of the periodic finger structures of the interdigitated gold electrodes are designed and validated using COMSOL® Multiphysics software by the application of known dielectric properties. The validated models are used to compute the electrical properties at different sensor states (blank, loaded with spores, and after sterilization). As a final result, we will derive and tabulate the frequency-dependent electrical parameters of the spore layer using a novel model that combines experimental data with numerical optimization techniques.}, language = {en} } @article{AbouzarSchoeningPoghossianetal.2008, author = {Abouzar, Maryam H. and Sch{\"o}ning, Michael Josef and Poghossian, Arshak and Christiaens, P. and Williams, O. A. and Wagner, P. and Haenen, K.}, title = {Feldeffektsensor auf nanokristalliner Diamantbasis}, series = {Sensoren und Messsysteme 2008 : 14. Fachtagung Ludwigsburg, 11. und 12. M{\"a}rz 2008 / VDI/VDE-Gesellschaft Mess- und Automatisierungstechnik}, journal = {Sensoren und Messsysteme 2008 : 14. Fachtagung Ludwigsburg, 11. und 12. M{\"a}rz 2008 / VDI/VDE-Gesellschaft Mess- und Automatisierungstechnik}, publisher = {VDI-Verl.}, address = {D{\"u}sseldorf}, isbn = {978-3-18-092011-5}, pages = {549 -- 558}, year = {2008}, language = {de} } @article{PoghossianWagnerSchoening2010, author = {Poghossian, Arshak and Wagner, H. and Sch{\"o}ning, Michael Josef}, title = {Automatisiertes „wafer level"-Testsystem zur Charakterisierung von siliziumbasierten Chemo- und Biosensoren}, series = {Sensoren und Messsysteme 2010 [Elektronische Ressource] : Vortr{\"a}ge der 15. ITG/GMA-Fachtagung vom 18. bis 19. Mai 2010 in N{\"u}rnberg / Informationstechnische Gesellschaft im VDE (ITG); VDI/VDE-Gesellschaft Mess- und Automatisierungstechnik (GMA)}, journal = {Sensoren und Messsysteme 2010 [Elektronische Ressource] : Vortr{\"a}ge der 15. ITG/GMA-Fachtagung vom 18. bis 19. Mai 2010 in N{\"u}rnberg / Informationstechnische Gesellschaft im VDE (ITG); VDI/VDE-Gesellschaft Mess- und Automatisierungstechnik (GMA)}, publisher = {VDE Verlag}, address = {Berlin}, isbn = {978-3-8007-3260-9}, pages = {89 -- 92}, year = {2010}, language = {de} } @article{GunGutkinLevetal.2011, author = {Gun, Jenny and Gutkin, Vitaly and Lev, Ovadia and Boyen, Hans-Gerd and Saitner, Marc and Wagner, Patrick and Olieslaeger, Marc D´ and Abouzar, Maryam H. and Poghossian, Arshak and Sch{\"o}ning, Michael Josef}, title = {Tracing gold nanoparticle charge by electrolyte-insulator-semiconductor devices}, series = {Journal of Physical Chemistry C. 115 (2011), H. 11}, journal = {Journal of Physical Chemistry C. 115 (2011), H. 11}, publisher = {American Cemical Society}, address = {Washington, DC}, isbn = {1932-7455}, pages = {4439 -- 4445}, year = {2011}, language = {en} } @article{PoghossianAbouzarChristiaensetal.2008, author = {Poghossian, Arshak and Abouzar, Maryam H. and Christiaens, P. and Williams, O. A. and Haenen, K. and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Sensing charged macromolecules with nanocrystalline diamond-based field-effect capacitive sensors}, series = {Journal of Contemporary Physics. 43 (2008), H. 2}, journal = {Journal of Contemporary Physics. 43 (2008), H. 2}, isbn = {1934-9378}, pages = {77 -- 81}, year = {2008}, language = {en} } @article{PoghossianAbouzarChristiaensetal.2007, author = {Poghossian, Arshak and Abouzar, Maryam H. and Christiaens, P. and Williams, O. A. and Haenen, K. and Wagner, P. and Sch{\"o}ning, Michael Josef}, title = {Nanocrystalline diamond-based field-effect (bio-)chemical sensor}, series = {8. Dresdner Sensor-Symposium : Sensoren f{\"u}r Umwelt, Klima und Sicherheit, Biosensoren und Biosysteme, Sensoren und Sensorsysteme f{\"u}r die Prozesstechnik, Trends in der Sensortechnik, Materialentwicklung f{\"u}r die Sensorik; 8. Dresdner Sensor-Symposium, 10. - 12. Dezember 2007, Dresden / Gerald Gerlach ... (Hg.)}, journal = {8. Dresdner Sensor-Symposium : Sensoren f{\"u}r Umwelt, Klima und Sicherheit, Biosensoren und Biosysteme, Sensoren und Sensorsysteme f{\"u}r die Prozesstechnik, Trends in der Sensortechnik, Materialentwicklung f{\"u}r die Sensorik; 8. Dresdner Sensor-Symposium, 10. - 12. Dezember 2007, Dresden / Gerald Gerlach ... (Hg.)}, publisher = {TUDpress, Verl. der Wissenschaften}, address = {Dresden}, isbn = {978-3-940046-45-1}, pages = {191 -- 194}, year = {2007}, language = {en} } @article{MuribYeapEurlingsetal.2016, author = {Murib, M. S. and Yeap, W. S. and Eurlings, Y. and Grinsven, B. van and Boyen, H.-G. and Conings, B. and Michiels, L. and Ameloot, Marcel and Carleer, R. and Warmer, J. and Kaul, P. and Haenen, K. and Sch{\"o}ning, Michael Josef and Ceuninck, W. de and Wagner, P.}, title = {Heat-transfer based characterization of DNA on synthetic sapphire chips}, series = {Sensors and Actuators B: Chemical}, volume = {230}, journal = {Sensors and Actuators B: Chemical}, number = {230}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0925-4005}, doi = {10.1016/j.snb.2016.02.027}, pages = {260 -- 271}, year = {2016}, abstract = {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.}, language = {en} }