@inproceedings{HuckBaeckerPoghossianetal.2011, author = {Huck, Christina and B{\"a}cker, Matthias and Poghossian, Arshak and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Bifunktionaler Sensorchip f{\"u}r den Nachweis von Gel{\"o}stwasserstoff}, isbn = {978-3942710-53-4}, doi = {10.5162/10dss2011/16.10}, pages = {325 -- 328}, year = {2011}, language = {de} } @article{GrinsvenBonStrauvenetal.2012, author = {Grinsven, Bart van and Bon, Natalie vanden and Strauven, Hannelore and Grieten, Lars and Murib, Mohammed and Jim{\´e}nez Monroy, Kathia L. and Janssens, Stoffel D. and Haenen, Ken and Sch{\"o}ning, Michael Josef and Vermeeren, Veronique and Ameloot, Marcel and Michiels, Luc and Thoelen, Ronald and Ceuninck, Ward de and Wagner, Patrick}, title = {Heat-Transfer Resistance at Solid-Liquid Interfaces: A Tool for The Detection of Single Nucleotide Polymorphisms in DNA.}, series = {ACS Nano}, volume = {6}, journal = {ACS Nano}, number = {3}, publisher = {ACS Publications}, address = {Washington, DC}, issn = {1936-086X}, doi = {10.1021/nn300147e}, pages = {2712 -- 2721}, year = {2012}, abstract = {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.}, language = {en} } @inproceedings{SchusserLeinhosPoghossianetal.2012, author = {Schusser, Sebastian and Leinhos, Marcel and Poghossian, Arshak and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Biopolymer-degradation monitoring by chip-­based impedance spectroscopy technique}, series = {Nanoscale Science and Technology (NS\&T´12) : Proceedings Book Humboldt Kolleg ; Tunisia, 17-19 March, 2012}, booktitle = {Nanoscale Science and Technology (NS\&T´12) : Proceedings Book Humboldt Kolleg ; Tunisia, 17-19 March, 2012}, editor = {Abdelghani, Adnane and Sch{\"o}ning, Michael Josef}, pages = {47 -- 47}, year = {2012}, language = {en} } @article{SchusserPoghossianBaeckeretal.2012, author = {Schusser, Sebastian and Poghossian, Arshak and B{\"a}cker, Matthias and Leinhos, Marcel and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Characterization of biodegradable polymers with capacitive field-effect sensors}, series = {Sensors and actuators B: Chemical}, volume = {187}, journal = {Sensors and actuators B: Chemical}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0925-4005}, doi = {10.1016/j.snb.2012.07.099}, pages = {2 -- 7}, year = {2012}, abstract = {In vitro studies of the degradation kinetic of biopolymers are essential for the design and optimization of implantable biomedical devices. In the presented work, a field-effect capacitive sensor has been applied for the real-time and in situ monitoring of degradation processes of biopolymers for the first time. The polymer-covered field-effect sensor is, in principle, capable to detect any changes in bulk, surface and interface properties of the polymer induced by degradation processes. The feasibility of this approach has been experimentally proven by using the commercially available biomedical polymer poly(D,L-lactic acid) (PDLLA) as a model system. PDLLA films of different thicknesses were deposited on the Ta₂O₅-gate surface of the field-effect structure from a polymer solution by means of spin-coating method. The polymer-modified field-effect sensors have been characterized by means of capacitance-voltage and impedance-spectroscopy method. The degradation of the PDLLA was accelerated by changing the degradation medium from neutral (pH 7.2) to alkaline (pH 9) condition, resulting in drastic changes in the capacitance and impedance spectra of the polymer-modified field-effect sensor.}, language = {en} } @article{MuribTranCeunincketal.2012, author = {Murib, Mohammed S. and Tran, Anh Quang and Ceuninck, Ward de and Sch{\"o}ning, Michael Josef and Nesladek, Milos and Serpeng{\"u}zel, Ali and Wagner, Patrick}, title = {Analysis of an optical biosensor based on elastic light scattering from diamond-, glass-, and sapphire microspheres}, series = {Physica Status Solidi A}, volume = {209}, journal = {Physica Status Solidi A}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.201100795}, pages = {1804 -- 1810}, year = {2012}, abstract = {Deoxyribonucleic acid (DNA) and protein recognition are now standard tools in biology. In addition, the special optical properties of microsphere resonators expressed by the high quality factor (Q-factor) of whispering gallery modes (WGMs) or morphology dependent resonances (MDRs) have attracted the attention of the biophotonic community. Microsphere-based biosensors are considered as powerful candidates to achieve label-free recognition of single molecules due to the high sensitivity of their WGMs. When the microsphere surface is modified with biomolecules, the effective refractive index and the effective size of the microsphere change resulting in a resonant wavelength shift. The transverse electric (TE) and the transverse magnetic (TM) elastic light scattering intensity of electromagnetic waves at 600 and 1400 nm are numerically calculated for DNA and unspecific binding of proteins to the microsphere surface. The effect of changing the optical properties was studied for diamond (refractive index 2.34), glass (refractive index 1.50), and sapphire (refractive index 1.75) microspheres with a 50 µm radius. The mode spacing, the linewidth of WGMs, and the shift of resonant wavelength due to the change in radius and refractive index, were analyzed by numerical simulations. Preliminary results of unspecific binding of biomolecules are presented. The calculated shift in WGMs can be used for biomolecules detection.}, language = {en} } @article{HuckPoghossianWagneretal.2012, author = {Huck, Christina and Poghossian, Arshak and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Combined amperometric/field-effect sensor for the detection of dissolved hydrogen}, series = {Sensors and actuators B: Chemical}, volume = {187}, journal = {Sensors and actuators B: Chemical}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0925-4005}, doi = {10.1016/j.snb.2012.10.050}, pages = {168 -- 173}, year = {2012}, abstract = {Real-time and reliable monitoring of the biogas process is crucial for a stable and efficient operation of biogas production in order to avoid digester breakdowns. The concentration of dissolved hydrogen (H₂) represents one of the key parameters for biogas process control. In this work, a one-chip integrated combined amperometric/field-effect sensor for monitoring the dissolved H₂ concentration has been developed for biogas applications. The combination of two different transducer principles might allow a more accurate and reliable measurement of dissolved H₂ as an early warning indicator of digester failures. The feasibility of the approach has been demonstrated by simultaneous amperometric/field-effect measurements of dissolved H₂ concentrations in electrolyte solutions. Both, the amperometric and the field-effect transducer show a linear response behaviour in the H₂ concentration range from 0.1 to 3\% (v/v) with a slope of 198.4 ± 13.7 nA/\% (v/v) and 14.9 ± 0.5 mV/\% (v/v), respectively.}, language = {en} } @inproceedings{BohrnMuchaWerneretal.2012, author = {Bohrn, Ulrich and Mucha, Andreas and Werner, Frederik and St{\"u}tz, Evamaria and B{\"a}cker, Matthias and Krumbe, Christoph and Schienle, Meinrad and Fleischer, Maximilian and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Detection of toxic chromium species in water using cellbased sensor systems}, isbn = {978-3-9813484-2-2}, doi = {10.5162/IMCS2012/P2.1.14}, pages = {1364 -- 1367}, year = {2012}, language = {en} } @inproceedings{BohrnStuetzFleischeretal.2012, author = {Bohrn, Ulrich and St{\"u}tz, Evamaria and Fleischer, Maximilian and Sch{\"o}ning, Michael Josef and Wagner, Patrick}, title = {Living cell-based gas sensor system for the detection of acetone in air}, isbn = {978-3-9813484-2-2}, doi = {10.5162/IMCS2012/3.2.3}, pages = {269 -- 272}, year = {2012}, language = {en} } @article{BohrnStuetzFleischeretal.2013, author = {Bohrn, Ulrich and St{\"u}tz, Evamaria and Fleischer, Maximilian and Sch{\"o}ning, Michael Josef and Wagner, Patrick}, title = {Using a cell-based gas biosensor for investigation of adverse effects of acetone vapors in vitro}, series = {Biosensors and Bioelectronics. 40 (2013), H. 1}, journal = {Biosensors and Bioelectronics. 40 (2013), H. 1}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {0956-5663}, pages = {393 -- 400}, year = {2013}, language = {en} } @article{MuribGrinsvenGrietenetal.2013, author = {Murib, M. S. and Grinsven, B. van and Grieten, L. and Janssens, S. D. and Vermeeren, V. and Eersels, K. and Broeders, J. and Ameloot, M. and Michiels, L. and Ceuninck, W. De and Haenen, K. and Sch{\"o}ning, Michael Josef and Wagner, Patrick}, title = {Electronic monitoring of chemical DNA denaturation on nanocrystalline diamond electrodes with different molarities and flow rates}, series = {Physica Status Solidi (A). Vol. 210 (2013), iss. 5}, journal = {Physica Status Solidi (A). Vol. 210 (2013), iss. 5}, publisher = {Wiley-VCH}, address = {Berlin}, issn = {0031-8965}, pages = {911 -- 917}, year = {2013}, language = {en} } @article{BohrnMuchaWerneretal.2013, author = {Bohrn, Ulrich and Mucha, Andreas and Werner, Frederik and Trattner, Barbara and B{\"a}cker, Matthias and Krumbe, Christoph and Schienle, Meinrad and St{\"u}tz, Evamaria and Schmitt-Landsiedel, Doris and Fleischer, Maximilian and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {A critical comparison of cell-based sensor systems for the detection of Cr (VI) in aquatic environment}, series = {Sensors and actuators. B: Chemical}, volume = {Vol. 182}, journal = {Sensors and actuators. B: Chemical}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-3077 (E-Journal); 0925-4005 (Print)}, pages = {58 -- 65}, year = {2013}, language = {en} } @article{ReisertGeisslerFloerkeetal.2013, author = {Reisert, Steffen and Geissler, Hanno and Fl{\"o}rke, Rudolf and Weiler, Christian and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Characterisation of aseptic sterilisation processes using an electronic nose}, series = {International journal of nanotechnology}, volume = {Vol. 10}, journal = {International journal of nanotechnology}, number = {No. 5-7}, publisher = {Inderscience Enterprises}, address = {Gen{\`e}ve}, issn = {1475-7435 (Print) 7141-8151 (Online)}, pages = {470 -- 484}, year = {2013}, language = {en} } @misc{IngebrandtWagnerSchoening2013, author = {Ingebrandt, Sven and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Engineering of functional interfaces / guest eds. Sven Ingebrandt ; Patrick Wagner ; Michael J. Sch{\"o}ning}, series = {Physica Status Solidi (A)}, volume = {Vol. 210}, journal = {Physica Status Solidi (A)}, number = {Iss. 5}, issn = {1521-396X (E-Journal); 1862-6319 (E-Journal); 0031-8965 (Print); 1862-6300 (Print)}, pages = {845}, year = {2013}, language = {en} } @inproceedings{SchusserBaeckerLeinhosetal.2013, author = {Schusser, Sebastian and B{\"a}cker, Matthias and Leinhos, Marcel and Krischer, M. and Wenzel, L. and Poghossian, Arshak and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Sensorkonzept zur in vitro Echtzeitmessung des Degradationsverhaltens von biodegradierbaren Biopolymeren}, series = {11. Dresdner Sensor-Symposium : 9.-11.12.2013}, booktitle = {11. Dresdner Sensor-Symposium : 9.-11.12.2013}, organization = {Dresdner Sensor-Symposium <11, 2013>}, isbn = {978-3-9813484-5-3}, pages = {174 -- 177}, year = {2013}, language = {de} } @inproceedings{OberlaenderReisertKirchneretal.2013, author = {Oberl{\"a}nder, Jan and Reisert, Steffen and Kirchner, Patrick and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Kalorimetrische Gassensoren zur H2O2-Detektion in aseptischen Sterilisationsprozessen}, series = {11. Dresdner Sensor-Symposium : 9.-11.12.2013}, booktitle = {11. Dresdner Sensor-Symposium : 9.-11.12.2013}, organization = {Dresdner Sensor-Symposium <11, 2013>}, isbn = {978-3-9813484-5-3}, pages = {234 -- 238}, year = {2013}, language = {de} } @inproceedings{HuckPoghossianBaeckeretal.2013, author = {Huck, Christina and Poghossian, Arshak and B{\"a}cker, Matthias and Zander, W. and Schubert, J. and Sukoyan, L. H. and Begoyan, V. and Buniatyan, V. V. and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Chemische Sensoren mit Bariumstrontiumtitanat als funktionelle Schicht zur Multiparameterdetektion}, series = {11. Dresdner Sensor-Symposium : 9.-11.12.2013}, booktitle = {11. Dresdner Sensor-Symposium : 9.-11.12.2013}, organization = {Dresdner Sensor-Symposium <11, 2013>}, isbn = {978-3-9813484-5-3}, pages = {368 -- 372}, year = {2013}, language = {de} } @article{ReisertSchneiderGeissleretal.2013, author = {Reisert, Steffen and Schneider, Benno and Geissler, Hanno and Gompel, Matthias van and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Multi-sensor chip for the investigation of different types of metal oxides for the detection of H2O2 in the ppm range}, series = {physica status solidi (a)}, volume = {210}, journal = {physica status solidi (a)}, number = {5}, publisher = {Wiley}, address = {Weinheim}, issn = {1862-6319}, pages = {898 -- 904}, year = {2013}, abstract = {In this work, a multi-sensor chip for the investigation of the sensing properties of different types of metal oxides towards hydrogen peroxide in the ppm range is presented. The fabrication process and physical characterization of the multi-sensor chip are described. Pure SnO2 and WO3 as well as Pd- and Pt-doped SnO2 films are characterized in terms of their sensitivity to H2O2. The sensing films have been prepared by drop-coating of water-dispensed nano-powders. A physical characterization, including scanning electron microscopy and X-ray diffraction analysis of the deposited metal-oxide films, was done. From the measurements in hydrogen peroxide atmosphere, it could be shown, that all of the tested metal oxide films are suitable for the detection of H2O2 in the ppm range. The highest sensitivity and reproducibility was achieved using Pt-doped SnO2. Calibration plot of a SnO2, WO3, Pt-, and Pd-doped SnO2 gas sensor for H2O2 concentrations in the ppm range.}, language = {en} } @article{HuckSchiffelsHerreraetal.2013, author = {Huck, Christina and Schiffels, Johannes and Herrera, Cony N. and Schelden, Maximilian and Selmer, Thorsten and Poghossian, Arshak and Baumann, Marcus and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Metabolic responses of Escherichia coli upon glucose pulses captured by a capacitive field-effect sensor}, series = {Physica Status Solidi (A)}, volume = {210}, journal = {Physica Status Solidi (A)}, number = {5}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0031-8965}, doi = {10.1002/pssa.201200900}, pages = {926 -- 931}, year = {2013}, abstract = {Living cells are complex biological systems transforming metabolites taken up from the surrounding medium. Monitoring the responses of such cells to certain substrate concentrations is a challenging task and offers possibilities to gain insight into the vitality of a community influenced by the growth environment. Cell-based sensors represent a promising platform for monitoring the metabolic activity and thus, the "welfare" of relevant organisms. In the present study, metabolic responses of the model bacterium Escherichia coli in suspension, layered onto a capacitive field-effect structure, were examined to pulses of glucose in the concentration range between 0.05 and 2 mM. It was found that acidification of the surrounding medium takes place immediately after glucose addition and follows Michaelis-Menten kinetic behavior as a function of the glucose concentration. In future, the presented setup can, therefore, be used to study substrate specificities on the enzymatic level and may as well be used to perform investigations of more complex metabolic responses. Conclusions and perspectives highlighting this system are discussed.}, language = {en} } @article{BaeckerRakowskiPoghossianetal.2013, author = {B{\"a}cker, Matthias and Rakowski, D. and Poghossian, Arshak and Biselli, Manfred and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Chip-based amperometric enzyme sensor system for monitoring of bioprocesses by flow-injection analysis}, series = {Journal of Biotechnology}, volume = {163}, journal = {Journal of Biotechnology}, number = {4}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0168-1656}, doi = {10.1016/j.jbiotec.2012.03.014}, pages = {371 -- 376}, year = {2013}, abstract = {A microfluidic chip integrating amperometric enzyme sensors for the detection of glucose, glutamate and glutamine in cell-culture fermentation processes has been developed. The enzymes glucose oxidase, glutamate oxidase and glutaminase were immobilized by means of cross-linking with glutaraldehyde on platinum thin-film electrodes integrated within a microfluidic channel. The biosensor chip was coupled to a flow-injection analysis system for electrochemical characterization of the sensors. The sensors have been characterized in terms of sensitivity, linear working range and detection limit. The sensitivity evaluated from the respective peak areas was 1.47, 3.68 and 0.28 μAs/mM for the glucose, glutamate and glutamine sensor, respectively. The calibration curves were linear up to a concentration of 20 mM glucose and glutamine and up to 10 mM for glutamate. The lower detection limit amounted to be 0.05 mM for the glucose and glutamate sensor, respectively, and 0.1 mM for the glutamine sensor. Experiments in cell-culture medium have demonstrated a good correlation between the glutamate, glutamine and glucose concentrations measured with the chip-based biosensors in a differential-mode and the commercially available instrumentation. The obtained results demonstrate the feasibility of the realized microfluidic biosensor chip for monitoring of bioprocesses.}, language = {en} } @article{SchusserLeinhosBaeckeretal.2013, author = {Schusser, Sebastian and Leinhos, Marcel and B{\"a}cker, Matthias and Poghossian, Arshak and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Impedance spectroscopy: A tool for real-time in situ monitoring of the degradation of biopolymers}, series = {Physica Status Solidi (A)}, volume = {210}, journal = {Physica Status Solidi (A)}, number = {5}, publisher = {Wiley}, address = {Weinheim}, issn = {1521-396X ; 0031-8965}, doi = {10.1002/pssa.201200941}, pages = {905 -- 910}, year = {2013}, abstract = {Investigation of the degradation kinetics of biodegradable polymers is essential for the development of implantable biomedical devices with predicted biodegradability. In this work, an impedimetric sensor has been applied for real-time and in situ monitoring of degradation processes of biopolymers. The sensor consists of two platinum thin-film electrodes covered by a polymer film to be studied. The benchmark biomedical polymer poly(D,L-lactic acid) (PDLLA) was used as a model system. PDLLA films were deposited on the sensor structure from a polymer solution by using the spin-coating method. The degradation kinetics of PDLLA films have been studied in alkaline solutions of pH 9 and 12 by means of an impedance spectroscopy (IS) method. Any changes in a polymer capacitance/resistance induced by water uptake and/or polymer degradation will modulate the global impedance of the polymer-covered sensor that can be used as an indicator of the polymer degradation. The degradation rate can be evaluated from the time-dependent impedance spectra. As expected, a faster degradation has been observed for PDLLA films exposed to pH 12 solution.}, language = {en} }