@article{ItabashiKosakaMiyamotoetal.2013,
  author    = {Itabashi, Akinori and Kosaka, Naoki and Miyamoto, Ko-ichiro and Wagner, Torsten and Sch{\"o}ning, Michael Josef},
  title     = {High-speed chemical imaging system based on front-side-illuminated LAPS},
  series = {Sensors and actuators B: Chemical},
  volume    = {182},
  journal   = {Sensors and actuators B: Chemical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-3077},
  doi       = {10.1016/j.snb.2013.03.016},
  pages     = {315 -- 321},
  year      = {2013},
  abstract  = {The chemical imaging sensor is a semiconductor-based chemical sensor that can visualize the spatial distribution of specific ions on the sensing surface. The conventional chemical imaging system based on the light-addressable potentiometric sensor (LAPS), however, required a long time to obtain a chemical image, due to the slow mechanical scan of a single light beam. For high-speed imaging, a plurality of light beams modulated at different frequencies can be employed to measure the ion concentrations simultaneously at different locations on the sensor plate by frequency division multiplex (FDM). However, the conventional measurement geometry of back-side illumination limited the bandwidth of the modulation frequency required for FDM measurement, because of the low-pass filtering characteristics of carrier diffusion in the Si substrate. In this study, a high-speed chemical imaging system based on front-side-illuminated LAPS was developed, which achieved high-speed spatiotemporal recording of pH change at a rate of 70 frames per second.},
  language  = {en}
}
@article{BandodkarMolinnusMirzaetal.2014,
  author    = {Bandodkar, Amay J. and Molinnus, Denise and Mirza, Omar and Guinovart, Tomas and Windmiller, Joshua R. and Valdes-Ramirez, Gabriela and Andrade, Francisco J. and Sch{\"o}ning, Michael Josef and Wang, Joseph},
  title     = {Epidermal tattoo potentiometric sodium sensors with wireless signal transduction for continuous non-invasive sweat monitoring},
  series = {Biosensors and bioelectronics},
  volume    = {54},
  journal   = {Biosensors and bioelectronics},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-4235 (E-Journal); 0956-5663 (Print)},
  doi       = {10.1016/j.bios.2013.11.039},
  pages     = {603 -- 609},
  year      = {2014},
  abstract  = {This article describes the fabrication, characterization and application of an epidermal temporary-transfer tattoo-based potentiometric sensor, coupled with a miniaturized wearable wireless transceiver, for real-time monitoring of sodium in the human perspiration. Sodium excreted during perspiration is an excellent marker for electrolyte imbalance and provides valuable information regarding an individual's physical and mental wellbeing. The realization of the new skin-worn non-invasive tattoo-like sensing device has been realized by amalgamating several state-of-the-art thick film, laser printing, solid-state potentiometry, fluidics and wireless technologies. The resulting tattoo-based potentiometric sodium sensor displays a rapid near-Nernstian response with negligible carryover effects, and good resiliency against various mechanical deformations experienced by the human epidermis. On-body testing of the tattoo sensor coupled to a wireless transceiver during exercise activity demonstrated its ability to continuously monitor sweat sodium dynamics. The real-time sweat sodium concentration was transmitted wirelessly via a body-worn transceiver from the sodium tattoo sensor to a notebook while the subjects perspired on a stationary cycle. The favorable analytical performance along with the wearable nature of the wireless transceiver makes the new epidermal potentiometric sensing system attractive for continuous monitoring the sodium dynamics in human perspiration during diverse activities relevant to the healthcare, fitness, military, healthcare and skin-care domains.},
  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}
}
@article{MiyamotoHirayamaWagneretal.2013,
  author    = {Miyamoto, Ko-ichiro and Hirayama, Yuji and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {Visualization of enzymatic reaction in a microfluidic channel using chemical imaging sensor},
  series = {Electrochimica acta},
  journal   = {Electrochimica acta},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-3859 (E-Journal); 0013-4686 (Print)},
  pages     = {Publ. online},
  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}
}
@misc{AbdelghaniMenaaObareetal.2013,
  author    = {Abdelghani, Adnane and Menaa, Bouzid and Obare, Sherine O. and Sch{\"o}ning, Michael Josef},
  title     = {Special issue on nanoscale science and technology / guest eds.: Adnane Abdelghani, Bouzid Menaa, Sherine O. Obare, Michael J. Sch{\"o}ning},
  series = {International journal of nanotechnology},
  volume    = {Vol. 10},
  journal   = {International journal of nanotechnology},
  number    = {No. 5-7},
  issn      = {1741-8151 (E-Journal), 1475-7435 (Print)},
  pages     = {373 -- 619},
  year      = {2013},
  language  = {en}
}
@inproceedings{TakenagaHerreraWerneretal.2013,
  author    = {Takenaga, Shoko and Herrera, Cony F. and Werner, Frederik and Biselli, Manfred and Schnitzler, Thomas and Sch{\"o}ning, Michael Josef and {\"O}hlschl{\"a}ger, Peter and Wagner, Torsten},
  title     = {Detection of the metabolic activity of cells by differential measurements based on a single light-addressable potentiometric sensor chip},
  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     = {63 -- 67},
  year      = {2013},
  language  = {en}
}
@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}
}
@article{TakenagaBiselliSchnitzleretal.2014,
  author    = {Takenaga, Shoko and Biselli, Manfred and Schnitzler, Thomas and {\"O}hlschl{\"a}ger, Peter and Wagner, Torsten and Sch{\"o}ning, Michael Josef},
  title     = {Toward multi-analyte bioarray sensors: LAPS-based on-chip determination of a Michaelis-Menten-like kinetics for cell culturing},
  series = {Physica status solidi A : Applications and materials science},
  volume    = {211},
  journal   = {Physica status solidi A : Applications and materials science},
  number    = {6},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1521-396X (E); 1862-6319 (E-Journal); 0031-8965 (Print); 1862-6300 (Print)},
  doi       = {10.1002/pssa.201330464},
  pages     = {1410 -- 1415},
  year      = {2014},
  abstract  = {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.},
  language  = {en}
}
@article{OberlaenderKirchnerBoyenetal.2014,
  author    = {Oberl{\"a}nder, Jan and Kirchner, Patrick and Boyen, Hans-Gerd and Sch{\"o}ning, Michael Josef},
  title     = {Detection of hydrogen peroxide vapor by use of manganese(IV) oxide as catalyst for calorimetric gas sensors},
  series = {Physica status solidi A: Applications and materials science},
  volume    = {211},
  journal   = {Physica status solidi A: Applications and materials science},
  number    = {6},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1521-396X (E-Journal); 1862-6319 (E-Journal); 0031-8965 (Print); 1862-6300 (Print)},
  doi       = {10.1002/pssa.201330359},
  pages     = {1372 -- 1376},
  year      = {2014},
  abstract  = {In this work, the catalyst manganese(IV) oxide (MnO2), of calorimetric gas sensors (to monitor the sterilization agent vaporized hydrogen peroxide) has been investigated in more detail. Chemical analyses by means of X-ray-induced photoelectron spectroscopy have been performed to unravel the surface chemistry prior and after exposure to hydrogen peroxide vapor at elevated temperature, as applied in the sterilization processes of beverage cartons. The surface characterization reveals a change in oxidation states of the metal oxide catalyst after exposure to hydrogen peroxide. Additionally, a cleaning effect of the catalyst, which itself is attached to the sensor surface by means of a polymer interlayer, could be observed.},
  language  = {en}
}
@article{GuoMiyamotoWagneretal.2014,
  author    = {Guo, Yuanyuan and Miyamoto, Ko-ichiro and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {Theoretical study and simulation of light-addressable potentiometric sensors},
  series = {Physica status solidi (A) : applications and materials},
  volume    = {211},
  journal   = {Physica status solidi (A) : applications and materials},
  number    = {6},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {0031-8965},
  doi       = {10.1002/pssa.201330354},
  pages     = {1467 -- 1472},
  year      = {2014},
  abstract  = {The light-addressable potentiometric sensor (LAPS) is a semiconductor-based potentiometric sensor using a light probe with an ability of detecting the concentration of biochemical species in a spatially resolved manner. As an important biomedical sensor, research has been conducted to improve its performance, for instance, to realize high-speed measurement. In this work, the idea of facilitating the device-level simulation, instead of using an equivalent-circuit model, is presented for detailed analysis and optimization of the performance of the LAPS. Both carrier distribution and photocurrent response have been simulated to provide new insight into both amplitude-mode and phase-mode operations of the LAPS. Various device parameters can be examined to effectively design and optimize the LAPS structures and setups for enhanced performance.},
  language  = {en}
}
@article{RiedelKartchemnikSchoeningetal.2014,
  author    = {Riedel, Marc and Kartchemnik, Julia and Sch{\"o}ning, Michael Josef and Lisdat, Fred},
  title     = {Impedimetric DNA detection - steps forward to sensorial application},
  series = {Analytical chemistry},
  volume    = {86 (2014)},
  journal   = {Analytical chemistry},
  number    = {15},
  publisher = {ACS Publications},
  address   = {Columbus},
  issn      = {1520-6882 (E-Journal); 0003-2700 (Print); 0096-4484 (Print)},
  doi       = {10.1021/ac501800q},
  pages     = {7867 -- 7874},
  year      = {2014},
  abstract  = {This study describes a label-free impedimetric sensor based on short ssDNA recognition elements for the detection of hybridization events. We concentrate on the elucidation of the influence of target length and recognition sequence position on the sensorial performance. The impedimetric measurements are performed in the presence of the redox system ferri-/ferrocyanide and show an increase in charge transfer resistance upon hybridization of ssDNA to the sensor surface. Investigations on the impedimetric signal stability demonstrate a clear influence of the buffers used during the sensor preparation and the choice of the passivating mercaptoalcanol compound. A stable sensor system has been developed, enabling a reproducible detection of 25mer target DNA in the low nanomolar range. After hybridization, a sensor regeneration can be reached with deionized water by adjustment of effective convection conditions, ensuring a sensor reusability. By investigations of longer targets with overhangs exposed to the solution, we can demonstrate applicability of the impedimetric detection for longer ssDNA. However, a decreasing charge transfer resistance change (ΔRct) is found by extending the overhang. As a strategy to increase the impedance change for longer target strands, the position of the recognition sequence can be designed in a way that a small overhang is exposed to the electrode surface. This is found to result in an increase in the relative Rct change. These results suggest that DNA and consequently negative charge near the electrode possess a larger impact on the impedimetric signal than DNA further away.},
  language  = {en}
}
@techreport{SchoeningSelmerBaumann2012,
  author    = {Sch{\"o}ning, Michael Josef and Selmer, Thorsten and Baumann, Marcus},
  title     = {Schlussbericht zum Projekt "Bio-LAPS" : Optimierung des Betriebs eines Biogasfermenters mit Hilfe eines Feldeffekt-Biosensors auf Basis eines lichtadressierbaren potentiometrischen Sensors (LAPS) : Laufzeit: 01.09.2008 bis 31.01.2012 : F{\"o}rderkennzeichen 07NR264 bzw.22026407},
  publisher = {BMELV},
  address   = {Berlin},
  pages     = {44 S.},
  year      = {2012},
  language  = {de}
}
@article{GuoSekiMiyamotoetal.2014,
  author    = {Guo, Yuanyuan and Seki, Kosuke and Miyamoto, Ko-ichiro and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {Novel photoexcitation method for light-addressable potentiometric sensor with higher spatial resolution},
  series = {Applied physics express : APEX},
  volume    = {7},
  journal   = {Applied physics express : APEX},
  number    = {6},
  publisher = {IOP},
  address   = {Bristol},
  issn      = {1882-0786 (E-Journa); 1882-0778 (Print)},
  doi       = {10.7567/APEX.7.067301},
  pages     = {067301-4},
  year      = {2014},
  abstract  = {A novel photoexcitation method for the light-addressable potentiometric sensor (LAPS) is proposed to achieve a higher spatial resolution of chemical images. The proposed method employs a combined light source that consists of a modulated light probe, which generates the alternating photocurrent signal, and a ring of constant illumination surrounding it. The constant illumination generates a sheath of carriers with increased concentration which suppresses the spread of photocarriers by enhanced recombination. A device simulation was carried out to verify the effect of constant illumination on the spatial resolution, which demonstrated that a higher spatial resolution can be obtained.},
  language  = {en}
}
@article{WagnerDollSchoening2014,
  author    = {Wagner, Patrick and Doll, Theodor and Sch{\"o}ning, Michael Josef},
  title     = {Engineering of functional interfaces / Patrick Wagner ; Theodor Doll ; Michael J. Sch{\"o}ning (eds.)},
  series = {Physica status solidi (A) : Applications and materials science},
  volume    = {211},
  journal   = {Physica status solidi (A) : Applications and materials science},
  number    = {6},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1521-396X (E-Book); 1862-6319 (E-Book); 0031-8965 (Print); 1862-6300 (Print)},
  doi       = {10.1002/pssa.201470241},
  pages     = {1339 -- 1339},
  year      = {2014},
  language  = {en}
}
@article{JildehWagnerSchoeningetal.2015,
  author    = {Jildeh, Zaid B. and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Pieper, Martin},
  title     = {Simulating the electromagnetic-thermal treatment of thin aluminium layers for adhesion improvement},
  series = {Physica status solidi (a)},
  volume    = {Vol. 212},
  journal   = {Physica status solidi (a)},
  number    = {6},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1862-6319},
  doi       = {10.1002/pssa.201431893},
  pages     = {1234 -- 1241},
  year      = {2015},
  abstract  = {A composite layer material used in packaging industry is made from joining layers of different materials using an adhesive. An important processing step in the production of aluminium-containing composites is the surface treatment and consequent coating of adhesive material on the aluminium surface. To increase adhesion strength between aluminium layer and the adhesive material, the foil is heat treated. For efficient heating, induction heating was considered as state-of-the-art treatment process. Due to the complexity of the heating process and the unpredictable nature of the heating source, the control of the process is not yet optimised. In this work, a finite element analysis of the process was established and various process parameters were studied. The process was simplified and modelled in 3D. The numerical model contains an air domain, an aluminium layer and a copper coil fitted with a magnetic field concentrating material. The effect of changing the speed of the aluminium foil (or rolling speed) was studied with the change of the coil current. Statistical analysis was used for generating a general control equation of coil current with changing rolling speed.},
  language  = {en}
}
@article{BreuerRaueKirschbaumetal.2015,
  author    = {Breuer, Lars and Raue, Markus and Kirschbaum, M. and Mang, Thomas and Sch{\"o}ning, Michael Josef and Thoelen, R. and Wagner, Torsten},
  title     = {Light-controllable polymeric material based on temperature-sensitive hydrogels with incorporated graphene oxide},
  series = {Physica status solidi (a)},
  volume    = {212},
  journal   = {Physica status solidi (a)},
  number    = {6},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1862-6319},
  doi       = {10.1002/pssa.201431944},
  pages     = {1368 -- 1374},
  year      = {2015},
  abstract  = {Poly(N-isopropylacrylamide) (PNIPAAm) hydrogel films with incorporated graphene oxide (GO) were developed and tested as light-stimulated actuators. GO dispersions were synthesized via Hummers method and characterized toward their optical properties and photothermal energy conversion. The hydrogels were prepared by means of photopolymerization. In addition, the influence of GO within the hydrogel network on the lower critical solution temperature (LCST) was investigated by differential scanning calorimetry (DSC). The optical absorbance and the response to illumination were determined as a function of GO concentration for thin hydrogel films. A proof of principle for the stimulation with light was performed.},
  language  = {en}
}
@article{DantismTakenagaWagneretal.2015,
  author    = {Dantism, S. and Takenaga, S. and Wagner, P. and Wagner, Torsten and Sch{\"o}ning, Michael Josef},
  title     = {Light-addressable Potentiometric Sensor (LAPS) Combined with Multi-chamber Structures to Investigate the Metabolic Activity of Cells},
  series = {Procedia Engineering},
  volume    = {120},
  journal   = {Procedia Engineering},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1877-7058},
  doi       = {10.1016/j.proeng.2015.08.647},
  pages     = {384 -- 387},
  year      = {2015},
  abstract  = {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.},
  language  = {en}
}
@article{PilasMarianoKeusgenetal.2015,
  author    = {Pilas, Johanna and Mariano, K. and Keusgen, M. and Selmer, Thorsten and Sch{\"o}ning, Michael Josef},
  title     = {Optimization of an Enzyme-based Multi-parameter Biosensor for Monitoring Biogas Processes},
  series = {Procedia Engineering},
  volume    = {120},
  journal   = {Procedia Engineering},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1877-7058},
  doi       = {10.1016/j.proeng.2015.08.702},
  pages     = {532 -- 535},
  year      = {2015},
  language  = {en}
}
@article{MiyamotoBingWagneretal.2015,
  author    = {Miyamoto, Ko-ichiro and Bing, Yu and Wagner, Torsten and Yoshinobu, Tatsuo and Sch{\"o}ning, Michael Josef},
  title     = {Visualization of Defects on a Cultured Cell Layer by Utilizing Chemical Imaging Sensor},
  series = {Procedia Engineering},
  volume    = {120},
  journal   = {Procedia Engineering},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1877-7058},
  doi       = {10.1016/j.proeng.2015.08.806},
  pages     = {936 -- 939},
  year      = {2015},
  abstract  = {The chemical imaging sensor is a field-effect sensor which is able to visualize both the distribution of ions (in LAPS mode) and the distribution of impedance (in SPIM mode) inthe sample. In this study, a novel wound-healing assay is proposed, in which the chemical imaging sensor operated in SPIM mode is applied to monitor the defect of a cell layer brought into proximity of the sensing surface.A reduced impedance inside the defect, which was artificially formed ina cell layer, was successfully visualized in a photocurrent image.},
  language  = {en}
}
@inproceedings{KreyerStollenwerkSchoening2013,
  author    = {Kreyer, J{\"o}rg and Stollenwerk, Dominik and Sch{\"o}ning, Michael Josef},
  title     = {Tagung des Forschernachwuchses der FH Aachen 20. November 2013 / ed.: J. Kreyer, D. Stollenwerk, M. J. Sch{\"o}ning},
  publisher = {FH Aachen},
  address   = {Aachen},
  pages     = {64 S.},
  year      = {2013},
  language  = {de}
}
@article{MiyamotoItabashiWagneretal.2014,
  author    = {Miyamoto, Ko-ichiro and Itabashi, Akinori and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {High-speed chemical imaging inside a microfluidic channel},
  series = {Sensors and actuators. B: Chemical},
  volume    = {194},
  journal   = {Sensors and actuators. B: Chemical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-3077 (E-Journal); 0925-4005 (Print)},
  doi       = {10.1016/j.snb.2013.12.090},
  pages     = {521 -- 527},
  year      = {2014},
  abstract  = {In this study, a high-speed chemical imaging system was developed for visualization of the interior of a microfluidic channel. A microfluidic channel was constructed on the sensor surface of the light-addressable potentiometric sensor (LAPS), on which the ion concentrations could be measured in parallel at up to 64 points illuminated by optical fibers. The temporal change of pH distribution inside the microfluidic channel was recorded at a maximum rate of 100 frames per second (fps). The high frame rate allowed visualization of moving interfaces and plugs in the channel even at a flow velocity of 111 mm/s, which suggests the feasibility of plug-based microfluidic devices for flow-injection analysis (FIA).},
  language  = {en}
}
@misc{AhlbornGerlachIkenetal.2012,
  author    = {Ahlborn, Kristina and Gerlach, Frank and Iken, Heiko and Sch{\"o}ning, Michael Josef and Vonau, Winfried},
  title     = {Miniaturisierte, potentiometrische Indikatorelektrode und Verfahren zu deren Herstellung : Offenlegungsschrift},
  pages     = {7 S.},
  year      = {2012},
  language  = {de}
}
@incollection{KirchnerReisertSchoening2014,
  author    = {Kirchner, Patrick and Reisert, Steffen and Sch{\"o}ning, Michael Josef},
  title     = {Calorimetric gas sensors for hydrogen peroxide monitoring in aseptic food processes},
  series = {Gas sensing fundamentals. (Springer Series on Chemical Sensors and Biosensors ; 15)},
  booktitle = {Gas sensing fundamentals. (Springer Series on Chemical Sensors and Biosensors ; 15)},
  publisher = {Springer},
  address   = {Heidelberg},
  isbn      = {978-3-642-54518-4 (Print) ; 978-3-642-54519-1 (Online)},
  doi       = {10.1007/5346_2013_51},
  pages     = {279 -- 309},
  year      = {2014},
  abstract  = {For the sterilisation of aseptic food packages it is taken advantage of the microbicidal properties of hydrogen peroxide (H2O2). Especially, when applied in vapour phase, it has shown high potential of microbial inactivation. In addition, it offers a high environmental compatibility compared to other chemical sterilisation agents, as it decomposes into oxygen and water, respectively. Due to a lack in sensory detection possibilities, a continuous monitoring of the H2O2 concentration was recently not available. Instead, the sterilisation efficacy is validated using microbiological tests. However, progresses in the development of calorimetric gas sensors during the last 7 years have made it possible to monitor the H2O2 concentration during operation. This chapter deals with the fundamentals of calorimetric gas sensing with special focus on the detection of gaseous hydrogen peroxide. A sensor principle based on a calorimetric differential set-up is described. Special emphasis is given to the sensor design with respect to the operational requirements under field conditions. The state-of-the-art regarding a sensor set-up for the on-line monitoring and secondly, a miniaturised sensor for in-line monitoring are summarised. Furthermore, alternative detection methods and a novel multi-sensor system for the characterisation of aseptic sterilisation processes are described.},
  language  = {en}
}
@article{SiqueiraMolinnusBegingetal.2014,
  author    = {Siqueira, Jose R. and Molinnus, Denise and Beging, Stefan and Sch{\"o}ning, Michael Josef},
  title     = {Incorporating a hybrid urease-carbon nanotubes sensitive nanofilm on capacitive field-effect sensors for urea detection},
  series = {Analytical chemistry},
  volume    = {86},
  journal   = {Analytical chemistry},
  number    = {11},
  publisher = {ACS Publications},
  address   = {Columbus},
  issn      = {1520-6882 (E-Journal); 0003-2700 (Print); 0096-4484 (Print)},
  doi       = {10.1021/ac500458s},
  pages     = {5370 -- 5375},
  year      = {2014},
  abstract  = {The ideal combination among biomolecules and nanomaterials is the key for reaching biosensing units with high sensitivity. The challenge, however, is to find out a stable and sensitive film architecture that can be incorporated on the sensor's surface. In this paper, we report on the benefits of incorporating a layer-by-layer (LbL) nanofilm of polyamidoamine (PAMAM) dendrimer and carbon nanotubes (CNTs) on capacitive electrolyte-insulator-semiconductor (EIS) field-effect sensors for detecting urea. Three sensor arrangements were studied in order to investigate the adequate film architecture, involving the LbL film with the enzyme urease: (i) urease immobilized directly onto a bare EIS [EIS-urease] sensor; (ii) urease atop the LbL film over the EIS [EIS-(PAMAM/CNT)-urease] sensor; and (iii) urease sandwiched between the LbL film and another CNT layer [EIS-(PAMAM/CNT)-urease-CNT]. The surface morphology of all three urea-based EIS biosensors was investigated by atomic force microscopy (AFM), while the biosensing abilities were studied by means of capacitance-voltage (C/V) and dynamic constant-capacitance (ConCap) measureaments at urea concentrations ranging from 0.1 mM to 100 mM. The EIS-urease and EIS-(PAMAM/CNT)-urease sensors showed similar sensitivity (∼18 mV/decade) and a nonregular signal behavior as the urea concentration increased. On the other hand, the EIS-(PAMAM/CNT)-urease-CNT sensor exhibited a superior output signal performance and higher sensitivity of about 33 mV/decade. The presence of the additional CNT layer was decisive to achieve a urea based EIS sensor with enhanced properties. Such sensitive architecture demonstrates that the incorporation of an adequate hybrid enzyme-nanofilm as sensing unit opens new prospects for biosensing applications using the field-effect sensor platform.},
  language  = {en}
}
@article{MuribYeapMartensetal.2014,
  author    = {Murib, Mohammed Sharif and Yeap, Weng-Siang and Martens, Daan and Bienstman, Peter and Ceuninck, Ward de and Grinsven, Bart van and Sch{\"o}ning, Michael Josef and Michiels, Luc and Haenen, Ken and Ameloot, Marcel and Serpeng{\"u}zel, Ali and Wagner, Patrick},
  title     = {Photonic detection and characterization of DNA using sapphire microspheres},
  series = {Journal of biomedical optics},
  volume    = {19},
  journal   = {Journal of biomedical optics},
  number    = {9},
  publisher = {SPIE},
  address   = {Bellingham},
  issn      = {1560-2281 (E-Journal); 1083-3668 (Print)},
  doi       = {10.1117/1.JBO.19.9.097006},
  pages     = {097006},
  year      = {2014},
  abstract  = {A microcavity-based deoxyribonucleic acid (DNA) optical biosensor is demonstrated for the first time using synthetic sapphire for the optical cavity. Transmitted and elastic scattering intensity at 1510 nm are analyzed from a sapphire microsphere (radius 500  μm, refractive index 1.77) on an optical fiber half coupler. The 0.43 nm angular mode spacing of the resonances correlates well with the optical size of the sapphire sphere. Probe DNA consisting of a 36-mer fragment was covalently immobilized on a sapphire microsphere and hybridized with a 29-mer target DNA. Whispering gallery modes (WGMs) were monitored before the sapphire was functionalized with DNA and after it was functionalized with single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA). The shift in WGMs from the surface modification with DNA was measured and correlated well with the estimated thickness of the add-on DNA layer. It is shown that ssDNA is more uniformly oriented on the sapphire surface than dsDNA. In addition, it is shown that functionalization of the sapphire spherical surface with DNA does not affect the quality factor (Q≈104) of the sapphire microspheres. The use of sapphire is especially interesting because this material is chemically resilient, biocompatible, and widely used for medical implants.},
  language  = {en}
}
@article{GuoMiyamotoWagneretal.2014,
  author    = {Guo, Yuanyuan and Miyamoto, Ko-ichiro and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {Device simulation of the light-addressable potentiometric sensor for the investigation of the spatial resolution},
  series = {Sensors and actuators B: Chemical},
  volume    = {204},
  journal   = {Sensors and actuators B: Chemical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-3077 (E-Journal); 0925-4005 (Print)},
  doi       = {10.1016/j.snb.2014.08.016},
  pages     = {659 -- 665},
  year      = {2014},
  abstract  = {As a semiconductor-based electrochemical sensor, the light-addressable potentiometric sensor (LAPS) can realize two dimensional visualization of (bio-)chemical reactions at the sensor surface addressed by localized illumination. Thanks to this imaging capability, various applications in biochemical and biomedical fields are expected, for which the spatial resolution is critically significant. In this study, therefore, the spatial resolution of the LAPS was investigated in detail based on the device simulation. By calculating the spatiotemporal change of the distributions of electrons and holes inside the semiconductor layer in response to a modulated illumination, the photocurrent response as well as the spatial resolution was obtained as a function of various parameters such as the thickness of the Si substrate, the doping concentration, the wavelength and the intensity of illumination. The simulation results verified that both thinning the semiconductor substrate and increasing the doping concentration could improve the spatial resolution, which were in good agreement with known experimental results and theoretical analysis. More importantly, new findings of interests were also obtained. As for the dependence on the wavelength of illumination, it was found that the known dependence was not always the case. When the Si substrate was thick, a longer wavelength resulted in a higher spatial resolution which was known by experiments. When the Si substrate was thin, however, a longer wavelength of light resulted in a lower spatial resolution. This finding was explained as an effect of raised concentration of carriers, which reduced the thickness of the space charge region. The device simulation was found to be helpful to understand the relationship between the spatial resolution and device parameters, to understand the physics behind it, and to optimize the device structure and measurement conditions for realizing higher performance of chemical imaging systems.},
  language  = {en}
}
@article{ReisertGeisslerWeileretal.2015,
  author    = {Reisert, Steffen and Geissler, H. and Weiler, C. and Wagner, P. and Sch{\"o}ning, Michael Josef},
  title     = {Multiple sensor-type system for monitoring the microbicidal effectiveness of aseptic sterilisation processes},
  series = {Food control},
  volume    = {47},
  journal   = {Food control},
  issn      = {1873-7129 (E-Journal); 0956-7135 (Print)},
  doi       = {10.1016/j.foodcont.2014.07.063},
  pages     = {615 -- 622},
  year      = {2015},
  abstract  = {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.},
  language  = {en}
}
@article{KhaydukovaZadorozhnayaKirsanovetal.2014,
  author    = {Khaydukova, M. M. and Zadorozhnaya, O. A. and Kirsanov, D. O. and Iken, Heiko and Rolka, David and Sch{\"o}ning, Michael Josef and Babain, V. A. and Vlasov, Yu. G. and Legin, A. V.},
  title     = {Multivariate processing of atomic-force microscopy images for detection of the response of plasticized polymeric membranes},
  series = {Russian journal of applied chemistry},
  volume    = {87},
  journal   = {Russian journal of applied chemistry},
  number    = {3},
  publisher = {Springer},
  address   = {Dordrecht},
  issn      = {1608-3296 (E-Journal); 1070-4272 (Print)},
  doi       = {10.1134/S1070427214030112},
  pages     = {307 -- 314},
  year      = {2014},
  abstract  = {The possibility of using the atomic-force microscopy as a method for detection of the analytical signal from plasticized polymeric sensor membranes was analyzed. The surfaces of cadmium-selective membranes based on two polymeric matrices were examined. The digital images were processed with multivariate image analysis techniques. A correlation was found between the surface profile of an ion-selective membrane and the concentration of the ion in solution.},
  language  = {en}
}
@article{YoshinobuMiyamotoWagneretal.2015,
  author    = {Yoshinobu, Tatsuo and Miyamoto, Ko-ichiro and Wagner, Torsten and Sch{\"o}ning, Michael Josef},
  title     = {Recent developments of chemical imaging sensor systems based on the principle of the light-addressable potentiometric sensor},
  series = {Sensors and actuators B: Chemical},
  volume    = {207, Part B},
  journal   = {Sensors and actuators B: Chemical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-3077 (E-Journal); 0925-4005 (Print)},
  doi       = {10.1016/j.snb.2014.09.002},
  pages     = {926 -- 932},
  year      = {2015},
  abstract  = {The light-addressable potentiometric sensor (LAPS) is an electrochemical sensor with a field-effect structure to detect the variation of the Nernst potential at its sensor surface, the measured area on which is defined by illumination. Thanks to this light-addressability, the LAPS can be applied to chemical imaging sensor systems, which can visualize the two-dimensional distribution of a particular target ion on the sensor surface. Chemical imaging sensor systems are expected to be useful for analysis of reaction and diffusion in various electrochemical and biological samples. Recent developments of LAPS-based chemical imaging sensor systems, in terms of the spatial resolution, measurement speed, image quality, miniaturization and integration with microfluidic devices, are summarized and discussed.},
  language  = {en}
}
@article{MuribYeapMartensetal.2015,
  author    = {Murib, M. S. and Yeap, W. S. and Martens, D. and Liu, X. and Bienstman, P. and Fahlman, M. and Sch{\"o}ning, Michael Josef and Michiels, L. and Haenen, K. and Serpeng{\"u}zel, A. and Wagner, Patrick},
  title     = {Photonic studies on polymer-coated sapphire-spheres : a model system for biological ligands},
  series = {Sensors and actuators A: Physical},
  volume    = {222},
  journal   = {Sensors and actuators A: Physical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-3069 (E-Journal); 0924-4247 (Print)},
  doi       = {10.1016/j.sna.2014.11.024},
  pages     = {212 -- 219},
  year      = {2015},
  abstract  = {In this study we show an optical biosensor concept, based on elastic light scattering from sapphire microspheres. Transmitted and elastic scattering intensity of the microspheres (radius 500 μm, refractive index 1.77) on an optical fiber half coupler is analyzed at 1510 nm. The 0.43 nm angular mode spacing of the resonances is comparable to the angular mode spacing value estimated using the optical size of the microsphere. The spectral linewidths of the resonances are in the order of 0.01 nm, which corresponds to quality factors of approximately 105. A polydopamine layer is used as a functionalizing agent on sapphire microspherical resonators in view of biosensor implementation. The varying layer thickness on the microsphere is determined as a function of the resonance wavelength shift. It is shown that polymer functionalization has a minor effect on the quality factor. This is a promising step toward the development of an optical biosensor.},
  language  = {en}
}
@article{GuoSekiMiyamotoetal.2014,
  author    = {Guo, Yuanyuan and Seki, Kosuke and Miyamoto, Ko-ichiro and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {Device simulation of the light-addressable potentiometric sensor with a novel photoexcitation method for a higher spatial resolution},
  series = {Procedia Engineering},
  volume    = {87},
  journal   = {Procedia Engineering},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1877-7058},
  doi       = {10.1016/j.proeng.2014.11.369},
  pages     = {456 -- 459},
  year      = {2014},
  abstract  = {A novel photoexcitation method for the light-addressable potentiometric sensor (LAPS) realized a higher spatial resolution of chemical imaging. In this method, a modulated light probe, which generates the alternating photocurrent signal, is surrounded by a ring of constant light, which suppresses the lateral diffusion of photocarriers by enhancing recombination. A device simulation verified that a higher spatial resolution could be obtained by adjusting the gap between the modulated and constant light. It was also found that a higher intensity and a longer wavelength of constant light was more effective. However, there exists a tradeoff between the spatial resolution and the amplitude of the photocurrent, and thus, the signal-to-noise ratio. A tilted incidence of constant light was applied, which could achieve even higher resolution with a smaller loss of photocurrent.},
  language  = {en}
}
@article{MiyamotoSekiWagneretal.2014,
  author    = {Miyamoto, K. and Seki, K. and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, T.},
  title     = {Enhancement of the spatial resolution of the chemical imaging sensor by a hybrid fiber-optic illumination},
  series = {Procedia Engineering},
  volume    = {87},
  journal   = {Procedia Engineering},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1877-7058},
  doi       = {10.1016/j.proeng.2014.11.563},
  pages     = {612 -- 615},
  year      = {2014},
  abstract  = {The chemical imaging sensor, which is based on the principle of the light-addressable potentiometric sensor (LAPS), is a powerful tool to visualize the spatial distribution of chemical species on the sensor surface. The spatial resolution of this sensor depends on the diffusion of photocarriers excited by a modulated light. In this study, a novel hybrid fiber-optic illumination was developed to enhance the spatial resolution. It consists of a modulated light probe to generate a photocurrent signal and a ring of constant light, which suppresses the lateral diffusion of minority carriers excited by the modulated light. It is demonstrated that the spatial resolution was improved from 92 μm to 68 μm.},
  language  = {en}
}
@inproceedings{KloockSchoening2007,
  author    = {Kloock, Joachim P. and Sch{\"o}ning, Michael Josef},
  title     = {Heavy metal detection with semiconductor devices based on PLD-prepared chalcogenide glass thin films},
  series = {Armenian Journal of Physics},
  booktitle = {Armenian Journal of Physics},
  issn      = {1829-1171},
  pages     = {95 -- 98},
  year      = {2007},
  language  = {en}
}
@inproceedings{WagnerYoshinobuSchoening2008,
  author    = {Wagner, Torsten and Yoshinobu, T. and Sch{\"o}ning, Michael Josef},
  title     = {Light-addressable potentiometric sensor as semiconductor-based sensor platform for (bio-) chemical sensing},
  series = {Armenian Journal of Physics},
  booktitle = {Armenian Journal of Physics},
  issn      = {1829-1171},
  pages     = {99 -- 103},
  year      = {2008},
  language  = {en}
}
@inproceedings{WernerYoshinobuMiyamotoetal.2014,
  author    = {Werner, Frederik and Yoshinobu, T. and Miyamoto, K. and Sch{\"o}ning, Michael Josef and Wagner, Torsten},
  title     = {Semiconductor-based sensors for imaging of chemical processes},
  series = {Sensoren und Messsysteme 2014 ; Beitr{\"a}ge der 17. GMA/ITG-Fachtagung vom 3. bis 4. Juni 2014 in N{\"u}rnberg. (ITG-Fachbericht ; 250)},
  booktitle = {Sensoren und Messsysteme 2014 ; Beitr{\"a}ge der 17. GMA/ITG-Fachtagung vom 3. bis 4. Juni 2014 in N{\"u}rnberg. (ITG-Fachbericht ; 250)},
  publisher = {VDE-Verl.},
  address   = {D{\"u}sseldorf},
  organization    = {VDI/VDE-Gesellschaft Mess- und Automatisierungstechnik},
  isbn      = {978-3-8007-3622-5},
  pages     = {1 -- 5},
  year      = {2014},
  language  = {en}
}
@inproceedings{OberlaenderKirchnerKeusgenetal.2014,
  author    = {Oberl{\"a}nder, Jan and Kirchner, Patrick and Keusgen, M. and Sch{\"o}ning, Michael Josef},
  title     = {Flexible polyimide-based calorimetric gas sensors for monitoring hy-drogen peroxide in sterilisation processes of aseptic filling machines},
  series = {Sensoren und Messsysteme 2014 ; Beitr{\"a}ge der 17. GMA/ITG-Fachtagung vom 3. bis 4. Juni 2014 in N{\"u}rnberg. (ITG-Fachbericht ; 250)},
  booktitle = {Sensoren und Messsysteme 2014 ; Beitr{\"a}ge der 17. GMA/ITG-Fachtagung vom 3. bis 4. Juni 2014 in N{\"u}rnberg. (ITG-Fachbericht ; 250)},
  publisher = {VDE-Verl.},
  address   = {D{\"u}sseldorf},
  organization    = {VDI/VDE-Gesellschaft Mess- und Automatisierungstechnik},
  isbn      = {978-3-8007-3622-5},
  pages     = {1 -- 4},
  year      = {2014},
  language  = {en}
}
@article{SchuetzWeissbeckerHummeletal.1997,
  author    = {Sch{\"u}tz, S. and Weißbecker, B. and Hummel, Hans E. and Sch{\"o}ning, Michael Josef and Riemer, A. and Kordos, P. and L{\"u}th, H.},
  title     = {Field effect transistor-insect antenna junction},
  series = {Naturwissenschaften},
  volume    = {84},
  journal   = {Naturwissenschaften},
  issn      = {1432-1904},
  pages     = {86 -- 88},
  year      = {1997},
  language  = {en}
}
@article{ThustSchoeningFrohnhoffetal.1996,
  author    = {Thust, Marion and Sch{\"o}ning, Michael Josef and Frohnhoff, S. and Arens-Fischer, R. and Kordos, P. and L{\"u}th, H.},
  title     = {Porous silicon as a substrate material for potentiometric biosensors},
  series = {Measurement Science and Technology},
  volume    = {7},
  journal   = {Measurement Science and Technology},
  number    = {1},
  doi       = {10.1088/0957-0233/7/1/003},
  pages     = {26 -- 29},
  year      = {1996},
  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}
}
@inproceedings{TakenagaWernerSawadaetal.2012,
  author    = {Takenaga, Shoko and Werner, Frederik and Sawada, Kazuaki and Sch{\"o}ning, Michael Josef},
  title     = {Comparison of label-free ACh image sensors based on CCD and LAPS},
  isbn      = {978-3-9813484-2-2},
  doi       = {10.5162/IMCS2012/4.2.6},
  pages     = {356 -- 359},
  year      = {2012},
  language  = {en}
}
@article{SchoeningBaecker2012,
  author    = {Sch{\"o}ning, Michael Josef and B{\"a}cker, Matthias},
  title     = {Chip-basierte Sensoren f{\"u}r die Biotechnik},
  volume    = {13},
  number    = {2},
  publisher = {BIOCOM},
  address   = {Berlin},
  issn      = {1611-0854},
  year      = {2012},
  language  = {de}
}
@article{WagnerMiyamotoWerneretal.2011,
  author    = {Wagner, Torsten and Miyamoto, K. and Werner, Frederik and Sch{\"o}ning, Michael Josef and Yoshinobu, T.},
  title     = {Utilising Digital Micro-Mirror Device (DMD) as Scanning Light Source for Light-Addressable Potentiometric Sensors (LAPS)},
  volume    = {9},
  number    = {2},
  publisher = {American Scientific Publishers},
  address   = {Stevenson Ranch, Calif.},
  doi       = {10.1166/sl.2011.1620},
  pages     = {812 -- 815},
  year      = {2011},
  language  = {en}
}
@inproceedings{MoritzYoshinobuFingeretal.2003,
  author    = {Moritz, Werner and Yoshinobu, Tatsuo and Finger, Friedhelm and Krause, Steffi and Sch{\"o}ning, Michael Josef},
  title     = {Amorphous silicon as semiconductor material for high resolution LAPS},
  series = {Eurosensors XVII : the 17th European Conference on Solid-State Transducers ; University of Minho, Guimar{\~a}es, Portugal, September 21 - 24, 2003},
  booktitle = {Eurosensors XVII : the 17th European Conference on Solid-State Transducers ; University of Minho, Guimar{\~a}es, Portugal, September 21 - 24, 2003},
  pages     = {48 -- 49},
  year      = {2003},
  language  = {en}
}
@inproceedings{ErmelenkoYoshinobuMourzinaetal.2003,
  author    = {Ermelenko, Y. and Yoshinobu, T. and Mourzina, Y. and Sch{\"o}ning, Michael Josef and Vlasov, Y. and Iwasaki, H.},
  title     = {A multisensor based on laser scanned silicon transducer (LSST): development and properties},
  series = {Eurosensors XVII : the 17th European Conference on Solid-State Transducers ; University of Minho, Guimar{\~a}es, Portugal, September 21 - 24, 2003},
  booktitle = {Eurosensors XVII : the 17th European Conference on Solid-State Transducers ; University of Minho, Guimar{\~a}es, Portugal, September 21 - 24, 2003},
  pages     = {72 -- 73},
  year      = {2003},
  language  = {en}
}
@inproceedings{YoshinobuSchoeningFingeretal.2003,
  author    = {Yoshinobu, T. and Sch{\"o}ning, Michael Josef and Finger, F. and Moritz, W. and Iwasaki, H.},
  title     = {Thin-film a-Si LAPS : Preparation and pH sensitivity},
  series = {Eurosensors XVII : the 17th European Conference on Solid-State Transducers ; University of Minho, Guimar{\~a}es, Portugal, September 21 - 24, 2003},
  booktitle = {Eurosensors XVII : the 17th European Conference on Solid-State Transducers ; University of Minho, Guimar{\~a}es, Portugal, September 21 - 24, 2003},
  pages     = {88 -- 89},
  year      = {2003},
  language  = {en}
}
@inproceedings{KloockSchubertErmelenkoetal.2006,
  author    = {Kloock, Joachim P. and Schubert, J. and Ermelenko, Y. and Vlasov, Y. G. and Bratov, A. and Sch{\"o}ning, Michael Josef},
  title     = {Thin-film sensors with chalcogenide glass materials - a general survey},
  series = {Biochemical sensing utilisation of micro- and nanotechnologies : Warsaw, [23rd - 26th] November 2005 / ed. by M. Mascini ...},
  booktitle = {Biochemical sensing utilisation of micro- and nanotechnologies : Warsaw, [23rd - 26th] November 2005 / ed. by M. Mascini ...},
  address   = {Warsaw},
  pages     = {92 -- 97},
  year      = {2006},
  language  = {en}
}
@inproceedings{KloockMorenoHuachupomaetal.2005,
  author    = {Kloock, Joachim P. and Moreno, Lia and Huachupoma, S. and Xu, J. and Wagner, Torsten and Bratov, A. and Doll, T. and Vlasov, Y. and Sch{\"o}ning, Michael Josef},
  title     = {Halbleiterbasierte Schwermetallsensorik auf der Basis von Chalkogenidgl{\"a}sern f{\"u}r zuk{\"u}nftige „Lab on Chip"-Anwendungen},
  series = {7. Dresdner Sensor-Symposium - Neue Herausforderungen und Anwendungen in der Sensortechnik},
  booktitle = {7. Dresdner Sensor-Symposium - Neue Herausforderungen und Anwendungen in der Sensortechnik},
  editor    = {Gerlach, Gerald},
  publisher = {TUDpress, Verl. der Wissenschaften},
  address   = {Dresden},
  isbn      = {3-938863-29-3},
  pages     = {221 -- 224},
  year      = {2005},
  language  = {de}
}
@inproceedings{WagnerYoshinobuOttoetal.2006,
  author    = {Wagner, Torsten and Yoshinobu, T. and Otto, R. and Rao, C. and Molina, R. and Sch{\"o}ning, Michael Josef},
  title     = {Licht-adressierbare potentiometrische Sensorsysteme - Konzepte und Anwendungen},
  series = {Sensoren und Mess-Systeme 2006 : Vortr{\"a}ge der 13. ITG/GMA-Fachtagung vom 13. bis 14.3.2006 in Freiburg/Breisgau},
  booktitle = {Sensoren und Mess-Systeme 2006 : Vortr{\"a}ge der 13. ITG/GMA-Fachtagung vom 13. bis 14.3.2006 in Freiburg/Breisgau},
  publisher = {VDE Verl.},
  address   = {Berlin},
  isbn      = {3-8007-2939-3},
  pages     = {165 -- 168},
  year      = {2006},
  language  = {de}
}
@article{SpelthahnSchubertSchoening2012,
  author    = {Spelthahn, Heiko and Schubert, J{\"u}rgen and Sch{\"o}ning, Michael Josef},
  title     = {D{\"u}nnschichtsensoren f{\"u}r die Schwermetallanalytik : Mikroelektroden auf Chalkogenidglasbasis},
  series = {GIT Labor-Fachzeitschrift},
  journal   = {GIT Labor-Fachzeitschrift},
  number    = {4},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  pages     = {285 -- 287},
  year      = {2012},
  abstract  = {Die Detektion von Schadstoffen repr{\"a}sentiert in der Umweltanalytik eine wichtige Aufgabenstellung. Gerade die Abwasser- bzw. Brauchwasseranalytik sowie die Prozesskontrolle haben einen hohen Stellenwert. Siliziumbasierte D{\"u}nnschichtsensoren bieten eine kosteng{\"u}nstige M{\"o}glichkeit, „online"-Messungen bzw. Vor-Ort-Messungen zeitnah durchzuf{\"u}hren. In dieser Arbeit wird ein potentiometrisches Sensorarray auf der Basis von Chalkogenidgl{\"a}sern zur Detektion von Schwermetallen in w{\"a}ssrigen Medien vorgestellt.},
  language  = {de}
}
@article{WarmerWagnerSchoeningetal.2015,
  author    = {Warmer, Johannes and Wagner, Patrick and Sch{\"o}ning, Michael Josef and Kaul, Peter},
  title     = {Detection of triacetone triperoxide using temperature cycled metal-oxide semiconductor gas sensors},
  series = {Physica status solidi (a)},
  volume    = {212},
  journal   = {Physica status solidi (a)},
  number    = {6},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1862-6319},
  doi       = {10.1002/pssa.201431882},
  pages     = {1289 -- 1298},
  year      = {2015},
  language  = {en}
}
@article{DelleHuckBaeckeretal.2015,
  author    = {Delle, Lotta E. and Huck, Christina and B{\"a}cker, Matthias and M{\"u}ller, Frank and Grandthyll, Samuel and Jacobs, Karin and Lilischkis, Rainer and Vu, Xuan T. and Sch{\"o}ning, Michael Josef and Wagner, Patrick and Thoelen, Roland and Weil, Maryam and Ingebrandt, Sven},
  title     = {Impedimetric immunosensor for the detection of histamine based on reduced graphene oxide},
  series = {Physica status solidi (a)},
  volume    = {212},
  journal   = {Physica status solidi (a)},
  number    = {6},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1862-6319},
  doi       = {10.1002/pssa.201431863},
  pages     = {1327 -- 1334},
  year      = {2015},
  language  = {en}
}
@article{YoshinobuMoritzFingeretal.2006,
  author    = {Yoshinobu, Tatsuo and Moritz, Werner and Finger, Friedhelm and Sch{\"o}ning, Michael Josef},
  title     = {Application of thin-film amorphous silicon to chemical imaging},
  series = {Nanostructured materials and hybrid composites for gas sensors and biomedical applications : symposium held April 18-20, 2006, San Francisco , California, U.S.A.},
  journal   = {Nanostructured materials and hybrid composites for gas sensors and biomedical applications : symposium held April 18-20, 2006, San Francisco , California, U.S.A.},
  number    = {Paper 0910-A-20-01},
  editor    = {Comini, Elisabetta},
  isbn      = {9781558998711},
  pages     = {1 -- 10},
  year      = {2006},
  language  = {en}
}
@article{TakenagaSchneiderErbayetal.2015,
  author    = {Takenaga, Shoko and Schneider, Benno and Erbay, E. and Biselli, Manfred and Schnitzler, Thomas and Sch{\"o}ning, Michael Josef and Wagner, Torsten},
  title     = {Fabrication of biocompatible lab-on-chip devices for biomedical applications by means of a 3D-printing process},
  series = {Physica status solidi (a)},
  volume    = {212},
  journal   = {Physica status solidi (a)},
  number    = {6},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1862-6319},
  doi       = {10.1002/pssa.201532053},
  pages     = {1347 -- 1352},
  year      = {2015},
  abstract  = {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.},
  language  = {en}
}
@inproceedings{BreuerRaueMangetal.2015,
  author    = {Breuer, Lars and Raue, Markus and Mang, Thomas and Sch{\"o}ning, Michael Josef and Thoelen, Ronald and Wagner, Torsten},
  title     = {Light-stimulated hydrogel actuators with incorporated graphene oxide for microfluidic applications},
  series = {12. Dresdner Sensor-Symposium 2015},
  booktitle = {12. Dresdner Sensor-Symposium 2015},
  doi       = {10.5162/12dss2015/P5.8},
  pages     = {206 -- 209},
  year      = {2015},
  language  = {en}
}
@article{MiyamatoSakakitaWagneretal.2015,
  author    = {Miyamato, Ko-ichiro and Sakakita, Sakura and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {Application of chemical imaging sensor to in-situ pH imaging in the vicinity of a corroding metal surface},
  series = {Electrochimica Acta},
  volume    = {183},
  journal   = {Electrochimica Acta},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0013-4686},
  doi       = {10.1016/j.electacta.2015.07.184},
  pages     = {137 -- 142},
  year      = {2015},
  abstract  = {The chemical imaging sensor was applied to in-situ pH imaging of the solution in the vicinity of a corroding surface of stainless steel under potentiostatic polarization. A test piece of polished stainless steel was placed on the sensing surface leaving a narrow gap filled with artificial seawater and the stainless steel was corroded under polarization. The pH images obtained during polarization showed correspondence between the region of lower pH and the site of corrosion. It was also found that the pH value in the gap became as low as 2 by polarization, which triggered corrosion.},
  language  = {en}
}
@article{HamadBilattoAdlyetal.2016,
  author    = {Hamad, E. M. and Bilatto, S. E. R. and Adly, N. Y. and Correa, D. S. and Wolfrum, B. and Sch{\"o}ning, Michael Josef and Offenh{\"a}usser, A. and Yakushenko, A.},
  title     = {Inkjet printing of UV-curable adhesive and dielectric inks for microfluidic devices},
  series = {Lab on a Chip},
  volume    = {16},
  journal   = {Lab on a Chip},
  number    = {1},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1473-0189},
  doi       = {10.1039/C5LC01195G},
  pages     = {70 -- 74},
  year      = {2016},
  abstract  = {Bonding of polymer-based microfluidics to polymer substrates still poses a challenge for Lab-On-a-Chip applications. Especially, when sensing elements are incorporated, patterned deposition of adhesives with curing at ambient conditions is required. Here, we demonstrate a fabrication method for fully printed microfluidic systems with sensing elements using inkjet and stereolithographic 3D-printing.},
  language  = {en}
}
@article{MiyamotoYuIsodaetal.2016,
  author    = {Miyamoto, Ko-ichiro and Yu, Bing and Isoda, Hiroko and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {Visualization of the recovery process of defects in a cultured cell layer by chemical imaging sensor},
  series = {Sensors and Actuators B: Chemical},
  volume    = {236},
  journal   = {Sensors and Actuators B: Chemical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2016.04.018},
  pages     = {965 -- 969},
  year      = {2016},
  abstract  = {The chemical imaging sensor is a field-effect sensor which is able to visualize both the distribution of ions (in LAPS mode) and the distribution of impedance (in SPIM mode) in the sample. In this study, a novel cell assay is proposed, in which the chemical imaging sensor operated in SPIM mode is applied to monitor the recovery of defects in a cell layer brought into proximity of the sensing surface. A reduced impedance at a defect formed artificially in a cell layer was successfully visualized in a photocurrent image. The cell layer was cultured over two weeks, during which the temporal change of the photocurrent distribution corresponding to the recovery of the defect was observed.},
  language  = {de}
}
@article{DantismTakenagaWagneretal.2016,
  author    = {Dantism, Shahriar and Takenaga, Shoko and Wagner, Patrick and Wagner, Torsten and Sch{\"o}ning, Michael Josef},
  title     = {Determination of the extracellular acidification of Escherichia coli K12 with a multi-​chamber-​based LAPS system},
  series = {Physica status solidi (a)},
  volume    = {213},
  journal   = {Physica status solidi (a)},
  number    = {6},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1862-6300},
  doi       = {10.1002/pssa.201533043},
  pages     = {1479 -- 1485},
  year      = {2016},
  abstract  = {On-line monitoring of the metabolic activity of microorganisms involved in intermediate stages of biogas production plays an important role to avoid undesirable "down times" during the biogas production. In order to control this process, an on-chip differential measuring system based on the light-addressable potentiometric sensor (LAPS) principle combined with a 3D-printed multi-chamber structure has been realized. As a test microorganism, Escherichia coli K12 (E. coli K12) were used for cell-based measurements. Multi-chamber structures were developed to determine the metabolic activity of E. coli K12 in suspension for a different number of cells, responding to the addition of a constant or variable amount of glucose concentrations, enabling differential and simultaneous measurements.},
  language  = {en}
}
@article{BreuerRaueStrobeletal.2016,
  author    = {Breuer, Lars and Raue, Markus and Strobel, M. and Mang, Thomas and Sch{\"o}ning, Michael Josef and Thoelen, R. and Wagner, Torsten},
  title     = {Hydrogels with incorporated graphene oxide as light-addressable actuator materials for cell culture environments in lab-on-chip systems},
  series = {Physica status solidi (a)},
  volume    = {213},
  journal   = {Physica status solidi (a)},
  number    = {6},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1862-6300},
  doi       = {10.1002/pssa.201533056},
  pages     = {1520 -- 1525},
  year      = {2016},
  abstract  = {Abstractauthoren Graphene oxide (GO) nanoparticles were incorporated in temperature-sensitive Poly(N-isopropylacrylamide) (PNIPAAm) hydrogels. The nanoparticles increase the light absorption and convert light energy into heat efficiently. Thus, the hydrogels with GO can be stimulated spatially resolved by illumination as it was demonstrated by IR thermography. The temporal progression of the temperature maximum was detected for different concentrations of GO within the polymer network. Furthermore, the compatibility of PNIPAAm hydrogels with GO and cell cultures was investigated. For this purpose, culture medium was incubated with hydrogels containing GO and the viability and morphology of chinese hamster ovary (CHO) cells was examined after several days of culturing in presence of this medium.},
  language  = {en}
}
@article{BertzSchoeningMolinnusetal.2024,
  author    = {Bertz, Morten and Sch{\"o}ning, Michael Josef and Molinnus, Denise and Homma, Takayuki},
  title     = {Influence of temperature, light, and H₂O₂ concentration on microbial spore inactivation: in-situ Raman spectroscopy combined with optical trapping},
  series = {Physica status solidi (a) applications and materials science},
  journal   = {Physica status solidi (a) applications and materials science},
  number    = {Early View},
  publisher = {Wiley-VCH},
  address   = {Berlin},
  issn      = {1862-6319 (Online)},
  doi       = {10.1002/pssa.202300866},
  pages     = {8 Seiten},
  year      = {2024},
  abstract  = {To gain insight on chemical sterilization processes, the influence of temperature (up to 70 °C), intense green light, and hydrogen peroxide (H₂O₂) concentration (up to 30\% in aqueous solution) on microbial spore inactivation is evaluated by in-situ Raman spectroscopy with an optical trap. Bacillus atrophaeus is utilized as a model organism. Individual spores are isolated and their chemical makeup is monitored under dynamically changing conditions (temperature, light, and H₂O₂ concentration) to mimic industrially relevant process parameters for sterilization in the field of aseptic food processing. While isolated spores in water are highly stable, even at elevated temperatures of 70 °C, exposure to H₂O₂ leads to a loss of spore integrity characterized by the release of the key spore biomarker dipicolinic acid (DPA) in a concentration-dependent manner, which indicates damage to the inner membrane of the spore. Intensive light or heat, both of which accelerate the decomposition of H₂O₂ into reactive oxygen species (ROS), drastically shorten the spore lifetime, suggesting the formation of ROS as a rate-limiting step during sterilization. It is concluded that Raman spectroscopy can deliver mechanistic insight into the mode of action of H₂O₂-based sterilization and reveal the individual contributions of different sterilization methods acting in tandem.},
  language  = {en}
}
@techreport{SiegertBongaertsWagneretal.2022,
  author    = {Siegert, Petra and Bongaerts, Johannes and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Selmer, Thorsten},
  title     = {Abschlussbericht zum Projekt zur {\"U}berwachung biotechnologischer Prozesse mittels Diacetyl-/Acetoin-Biosensor und Evaluierung von Acetoin-Reduktasen zur Verwendung in Biotransformationen},
  address   = {Aachen},
  organization    = {FH Aachen},
  pages     = {16 Seiten},
  year      = {2022},
  language  = {de}
}
@article{IkenBronderGoretzkietal.2019,
  author    = {Iken, Heiko and Bronder, Thomas and Goretzki, Alexander and Kriesel, Jana and Ahlborn, Kristina and Gerlach, Frank and Vonau, Winfried and Zander, Willi and Schubert, J{\"u}rgen and Sch{\"o}ning, Michael Josef},
  title     = {Development of a Combined pH- and Redox-Sensitive Bi-Electrode Glass Thin-Film Sensor},
  series = {physica status solidi a : applications and materials sciences},
  volume    = {216},
  journal   = {physica status solidi a : applications and materials sciences},
  number    = {12},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1862-6319},
  doi       = {10.1002/pssa.201900114},
  pages     = {1 -- 8},
  year      = {2019},
  language  = {en}
}
@article{MuschallikKippReckeretal.2020,
  author    = {Muschallik, Lukas and Kipp, Carina Ronja and Recker, Inga and Bongaerts, Johannes and Pohl, Martina and Gelissen, Melanie and Sch{\"o}ning, Michael Josef and Selmer, Thorsten and Siegert, Petra},
  title     = {Synthesis of α-hydroxy ketones and vicinal diols with the Bacillus licheniformis DSM 13T butane-2, 3-diol dehydrogenase},
  series = {Journal of Biotechnology},
  volume    = {202},
  journal   = {Journal of Biotechnology},
  number    = {Vol. 324},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {2590-1559},
  doi       = {10.1016/j.jbiotec.2020.09.016},
  pages     = {61 -- 70},
  year      = {2020},
  abstract  = {The enantioselective synthesis of α-hydroxy ketones and vicinal diols is an intriguing field because of the broad applicability of these molecules. Although, butandiol dehydrogenases are known to play a key role in the production of 2,3-butandiol, their potential as biocatalysts is still not well studied. Here, we investigate the biocatalytic properties of the meso-butanediol dehydrogenase from Bacillus licheniformis DSM 13T (BlBDH). The encoding gene was cloned with an N-terminal StrepII-tag and recombinantly overexpressed in E. coli. BlBDH is highly active towards several non-physiological diketones and α-hydroxyketones with varying aliphatic chain lengths or even containing phenyl moieties. By adjusting the reaction parameters in biotransformations the formation of either the α-hydroxyketone intermediate or the diol can be controlled.},
  language  = {en}
}
@article{MuschallikMolinnusJablonskietal.2020,
  author    = {Muschallik, Lukas and Molinnus, Denise and Jablonski, Melanie and Kipp, Carina Ronja and Bongaerts, Johannes and Pohl, Martina and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Selmer, Thorsten and Siegert, Petra},
  title     = {Synthesis of α-hydroxy ketones and vicinal (R, R)-diols by Bacillus clausii DSM 8716ᵀ butanediol dehydrogenase},
  series = {RSC Advances},
  volume    = {10},
  journal   = {RSC Advances},
  publisher = {Royal Society of Chemistry (RSC)},
  address   = {Cambridge},
  issn      = {2046-2069},
  doi       = {10.1039/D0RA02066D},
  pages     = {12206 -- 12216},
  year      = {2020},
  abstract  = {α-hydroxy ketones (HK) and 1,2-diols are important building blocks for fine chemical synthesis. Here, we describe the R-selective 2,3-butanediol dehydrogenase from B. clausii DSM 8716ᵀ (BcBDH) that belongs to the metal-dependent medium chain dehydrogenases/reductases family (MDR) and catalyzes the selective asymmetric reduction of prochiral 1,2-diketones to the corresponding HK and, in some cases, the reduction of the same to the corresponding 1,2-diols. Aliphatic diketones, like 2,3-pentanedione, 2,3-hexanedione, 5-methyl-2,3-hexanedione, 3,4-hexanedione and 2,3-heptanedione are well transformed. In addition, surprisingly alkyl phenyl dicarbonyls, like 2-hydroxy-1-phenylpropan-1-one and phenylglyoxal are accepted, whereas their derivatives with two phenyl groups are not substrates. Supplementation of Mn²⁺ (1 mM) increases BcBDH's activity in biotransformations. Furthermore, the biocatalytic reduction of 5-methyl-2,3-hexanedione to mainly 5-methyl-3-hydroxy-2-hexanone with only small amounts of 5-methyl-2-hydroxy-3-hexanone within an enzyme membrane reactor is demonstrated.},
  language  = {en}
}
@article{YoshinobuMiyamotoWerneretal.2017,
  author    = {Yoshinobu, Tatsuo and Miyamoto, Ko-ichiro and Werner, Frederik and Poghossian, Arshak and Wagner, Torsten and Sch{\"o}ning, Michael Josef},
  title     = {Light-addressable potentiometric sensors for quantitative spatial imaging of chemical species},
  series = {Annual Review of Analytical Chemistry},
  volume    = {10},
  journal   = {Annual Review of Analytical Chemistry},
  publisher = {Annual Reviews},
  address   = {Palo Alto, Calif.},
  issn      = {1936-1327},
  doi       = {10.1146/annurev-anchem-061516-045158},
  pages     = {225 -- 246},
  year      = {2017},
  abstract  = {A light-addressable potentiometric sensor (LAPS) is a semiconductor-based chemical sensor, in which a measurement site on the sensing surface is defined by illumination. This light addressability can be applied to visualize the spatial distribution of pH or the concentration of a specific chemical species, with potential applications in the fields of chemistry, materials science, biology, and medicine. In this review, the features of this chemical imaging sensor technology are compared with those of other technologies. Instrumentation, principles of operation, and various measurement modes of chemical imaging sensor systems are described. The review discusses and summarizes state-of-the-art technologies, especially with regard to the spatial resolution and measurement speed; for example, a high spatial resolution in a submicron range and a readout speed in the range of several tens of thousands of pixels per second have been achieved with the LAPS. The possibility of combining this technology with microfluidic devices and other potential future developments are discussed.},
  language  = {en}
}
@article{BaeckerPouyeshmanSchnitzleretal.2011,
  author    = {B{\"a}cker, Matthias and Pouyeshman, S. and Schnitzler, Thomas and Poghossian, Arshak and Wagner, Patrick and Biselli, Manfred and Sch{\"o}ning, Michael Josef},
  title     = {A silicon-based multi-sensor chip for monitoring of fermentation processes},
  series = {Physica status solidi (a) : applications and material science. 208 (2011), H. 6},
  journal   = {Physica status solidi (a) : applications and material science. 208 (2011), H. 6},
  publisher = {Wiley},
  address   = {Weinheim},
  isbn      = {1862-6319},
  pages     = {1364 -- 1369},
  year      = {2011},
  language  = {en}
}
@article{AbouzarPoghossianPedrazaetal.2011,
  author    = {Abouzar, Maryam H. and Poghossian, Arshak and Pedraza, A. M. and Gandhi, D. and Ingebrandt, S. and Moritz, W. and Sch{\"o}ning, Michael Josef},
  title     = {An array of field-effect nanoplate SOI capacitors for (bio-)chemical sensing},
  series = {Biosensors and Bioelectronics. 26 (2011), H. 6},
  journal   = {Biosensors and Bioelectronics. 26 (2011), H. 6},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {0956-5663},
  pages     = {3023 -- 3028},
  year      = {2011},
  language  = {en}
}
@article{PoghossianCherstvySchoening2004,
  author    = {Poghossian, Arshak and Cherstvy, A. and Sch{\"o}ning, Michael Josef},
  title     = {Possibilities and limitations of label-free detection of DNA hybridization with field-effect based devices},
  series = {Digest of technical papers : September 12 - 15, 2004, Rome, Italy, Pontificia Universitas Sancto Thoma Aquinate in Urbe / [conference chairperson: C. Di Natale].},
  journal   = {Digest of technical papers : September 12 - 15, 2004, Rome, Italy, Pontificia Universitas Sancto Thoma Aquinate in Urbe / [conference chairperson: C. Di Natale].},
  address   = {Roma},
  isbn      = {88-7621-282-5},
  pages     = {173 -- 176},
  year      = {2004},
  language  = {en}
}
@article{SiqueiraMakiPaulovichetal.2010,
  author    = {Siqueira, Jose R. and Maki, Rafael M. and Paulovich, Fernando V. and Werner, Frederik and Poghossian, Arshak and Oliveira, Maria C. F. de and Zucolotto, Valtencir and Oliveira, Osvaldo N. Jr. and Sch{\"o}ning, Michael Josef},
  title     = {Use of Information Visualization Methods Eliminating Cross Talk in Multiple Sensing Units Investigated for a Light-Addressable Potentiometric Sensor},
  series = {Analytical Chemistry (2010)},
  journal   = {Analytical Chemistry (2010)},
  isbn      = {0003-2700},
  pages     = {61 -- 65},
  year      = {2010},
  language  = {en}
}
@article{DollWagnerWagneretal.2016,
  author    = {Doll, Theodor and Wagner, Torsten and Wagner, Patrick and Sch{\"o}ning, Michael Josef},
  title     = {Engineering of functional interfaces / Theodor Doll ; Torsten Wagner ; Patrick Wagner ; Michael J. Sch{\"o}ning (eds.)},
  series = {Physica status solidi (a)},
  volume    = {213},
  journal   = {Physica status solidi (a)},
  number    = {6},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1862-6319},
  doi       = {10.1002/pssa.201670641},
  pages     = {1393 -- 1394},
  year      = {2016},
  language  = {en}
}
@article{MiyamotoSatoAbeetal.2016,
  author    = {Miyamoto, Ko-Ichiro and Sato, Takuya and Abe, Minami and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {Light-addressable potentiometric sensor as a sensing element in plug-based microfluidic devices},
  series = {Micromachines},
  volume    = {7},
  journal   = {Micromachines},
  number    = {7},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2072-666X},
  doi       = {10.3390/mi7070111},
  pages     = {111},
  year      = {2016},
  abstract  = {A plug-based microfluidic system based on the principle of the light-addressable potentiometric sensor (LAPS) is proposed. The LAPS is a semiconductor-based chemical sensor, which has a free addressability of the measurement point on the sensing surface. By combining a microfluidic device and LAPS, ion sensing can be performed anywhere inside the microfluidic channel. In this study, the sample solution to be measured was introduced into the channel in a form of a plug with a volume in the range of microliters. Taking advantage of the light-addressability, the position of the plug could be monitored and pneumatically controlled. With the developed system, the pH value of a plug with a volume down to 400 nL could be measured. As an example of plug-based operation, two plugs were merged in the channel, and the pH change was detected by differential measurement.},
  language  = {en}
}
@article{WeldenSchejaSchoeningetal.2018,
  author    = {Welden, Rene and Scheja, Sabrina and Sch{\"o}ning, Michael Josef and Wagner, Patrick and Wagner, Torsten},
  title     = {Electrochemical Evaluation of Light-Addressable Electrodes Based on TiO2 for the Integration in Lab-on-Chip Systems},
  series = {physica status solidi a : applications and materials sciences},
  volume    = {215},
  journal   = {physica status solidi a : applications and materials sciences},
  number    = {15},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1862-6319},
  doi       = {10.1002/pssa.201800150},
  pages     = {Article number 1800150},
  year      = {2018},
  abstract  = {In lab-on-chip systems, electrodes are important for the manipulation (e.g., cell stimulation, electrolysis) within such systems. An alternative to commonly used electrode structures can be a light-addressable electrode. Here, due to the photoelectric effect, the conducting area can be adjusted by modification of the illumination area which enables a flexible control of the electrode. In this work, titanium dioxide based light-addressable electrodes are fabricated by a sol-gel technique and a spin-coating process, to deposit a thin film on a fluorine-doped tin oxide glass. To characterize the fabricated electrodes, the thickness, and morphological structure are measured by a profilometer and a scanning electron microscope. For the electrochemical behavior, the dark current and the photocurrent are determined for various film thicknesses. For the spatial resolution behavior, the dependency of the photocurrent while changing the area of the illuminated area is studied. Furthermore, the addressing of single fluid compartments in a three-chamber system, which is added to the electrode, is demonstrated.},
  language  = {en}
}
@article{JildehOberlaenderKirchneretal.2018,
  author    = {Jildeh, Zaid B. and Oberl{\"a}nder, Jan and Kirchner, Patrick and Wagner, Patrick H. and Sch{\"o}ning, Michael Josef},
  title     = {Thermocatalytic Behavior of Manganese (IV) Oxide as Nanoporous Material on the Dissociation of a Gas Mixture Containing Hydrogen Peroxide},
  series = {Nanomaterials},
  volume    = {8},
  journal   = {Nanomaterials},
  number    = {4},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2079-4991},
  doi       = {10.3390/nano8040262},
  pages     = {Artikel 262},
  year      = {2018},
  abstract  = {In this article, we present an overview on the thermocatalytic reaction of hydrogen peroxide (H₂O₂) gas on a manganese (IV) oxide (MnO₂) catalytic structure. The principle of operation and manufacturing techniques are introduced for a calorimetric H₂O₂ gas sensor based on porous MnO₂. Results from surface analyses by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) of the catalytic material provide indication of the H₂O₂ dissociation reaction schemes. The correlation between theory and the experiments is documented in numerical models of the catalytic reaction. The aim of the numerical models is to provide further information on the reaction kinetics and performance enhancement of the porous MnO₂ catalyst.},
  language  = {en}
}
@article{BaeckerRakowskiKrappenetal.2017,
  author    = {B{\"a}cker, M. and Rakowski, D. and Krappen, E. and Sch{\"o}ning, Michael Josef},
  title     = {Reinigungsprozesse in der Lebensmittelindustrie. Entwicklung eines Demonstrators zur {\"U}berwachung},
  series = {GIT Labor-Fachzeitschrift},
  volume    = {61},
  journal   = {GIT Labor-Fachzeitschrift},
  number    = {8},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {0016-3538},
  pages     = {26 -- 28},
  year      = {2017},
  language  = {de}
}
@article{PilasYaziciSelmeretal.2018,
  author    = {Pilas, Johanna and Yazici, Y. and Selmer, Thorsten and Keusgen, M. and Sch{\"o}ning, Michael Josef},
  title     = {Application of a portable multi-analyte biosensor for organic acid determination in silage},
  series = {Sensors},
  volume    = {18},
  journal   = {Sensors},
  number    = {5},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {1424-8220},
  doi       = {10.3390/s18051470},
  pages     = {12 Seiten},
  year      = {2018},
  abstract  = {Multi-analyte biosensors may offer the opportunity to perform cost-effective and rapid analysis with reduced sample volume, as compared to electrochemical biosensing of each analyte individually. This work describes the development of an enzyme-based biosensor system for multi-parametric determination of four different organic acids. The biosensor array comprises five working electrodes for simultaneous sensing of ethanol, formate, d-lactate, and l-lactate, and an integrated counter electrode. Storage stability of the biosensor was evaluated under different conditions (stored at +4 °C in buffer solution and dry at -21 °C, +4 °C, and room temperature) over a period of 140 days. After repeated and regular application, the individual sensing electrodes exhibited the best stability when stored at -21 °C. Furthermore, measurements in silage samples (maize and sugarcane silage) were conducted with the portable biosensor system. Comparison with a conventional photometric technique demonstrated successful employment for rapid monitoring of complex media.},
  language  = {en}
}
@article{DantismRoehlenWagneretal.2018,
  author    = {Dantism, Shahriar and R{\"o}hlen, Desiree and Wagner, Torsten and Wagner, Patrick and Sch{\"o}ning, Michael Josef},
  title     = {Optimization of Cell-Based Multi-Chamber LAPS Measurements Utilizing FPGA-Controlled Laser-Diode Modules},
  series = {physica status solidi a : applications and materials sciences},
  volume    = {215},
  journal   = {physica status solidi a : applications and materials sciences},
  number    = {15},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1862-6319},
  doi       = {10.1002/pssa.201800058},
  pages     = {Article number 1800058},
  year      = {2018},
  abstract  = {A light-addressable potentiometric sensor (LAPS) is a field-effect-based potentiometric device, which detects concentration changes of an analyte solution on the sensor surface in a spatially resolved way. It uses a light source to generate electron-hole pairs inside the semiconductor, which are separated in the depletion region due to an applied bias voltage across the sensor structure and hence, a surface-potential-dependent photocurrent can be read out. However, depending on the beam angle of the light source, scattering effects can occur, which influence the recorded signal in LAPS-based differential measurements. To solve this problem, a novel illumination unit based on a field programmable gate array (FPGA) consisting of 16 small-sized tunable infrared laser-diode modules (LDMs) is developed. Due to the improved focus of the LDMs with a beam angle of only 2 mrad, undesirable scattering effects are minimized. Escherichia coli (E. coli) K12 bacteria are used as a test microorganism to study the extracellular acidification on the sensor surface. Furthermore, a salt bridge chamber is built up and integrated with the LAPS system enabling multi-chamber differential measurements with a single Ag/AgCl reference electrode.},
  language  = {en}
}
@article{VahidpourOberlaenderSchoening2018,
  author    = {Vahidpour, Farnoosh and Oberl{\"a}nder, Jan and Sch{\"o}ning, Michael Josef},
  title     = {Flexible Calorimetric Gas Sensors for Detection of a Broad Concentration Range of Gaseous Hydrogen Peroxide: A Step Forward to Online Monitoring of Food-Package Sterilization Processes},
  series = {Phys. Status Solidi A},
  volume    = {215},
  journal   = {Phys. Status Solidi A},
  number    = {15},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  doi       = {10.1002/pssa.201800044},
  pages     = {Artikel 1800044},
  year      = {2018},
  abstract  = {In this study, flexible calorimetric gas sensors are developed for specificdetection of gaseous hydrogen peroxide (H₂O₂) over a wide concentrationrange, which is used in sterilization processes for aseptic packaging industry.The flexibility of these sensors is an advantage for identifying the chemical components of the sterilant on the corners of the food boxes, so-called "coldspots", as critical locations in aseptic packaging, which are of great importance. These sensors are fabricated on flexible polyimide films by means of thin-film technique. Thin layers of titanium and platinum have been deposited on polyimide to define the conductive structures of the sensors. To detect the high-temperature evaporated H₂O₂, a differential temperature set-up is proposed. The sensors are evaluated in a laboratory-scaled sterilizationsystem to simulate the sterilization process. The concentration range of the evaporated H₂O₂ from 0 to 7.7\% v/v was defined and the sensors have successfully detected high as well as low H₂O₂ concentrations with a sensitivity of 5.04 °C/\% v/v. The characterizations of the sensors confirm their precise fabrication, high sensitivity and the novelty of low H₂O₂ concentration detections for future inline monitoring of food-package sterilization.},
  language  = {en}
}
@article{MoraisSilvaDantasetal.2019,
  author    = {Morais, Paulo V. and Silva, Anielle C. A. and Dantas, Noelio O. and Sch{\"o}ning, Michael Josef and Siqueira, Jos{\´e} R., Jr.},
  title     = {Hybrid Layer-by-Layer Film of Polyelectrolytes-Embedded Catalytic CoFe2O4 Nanocrystals as Sensing Units in Capacitive Electrolyte-Insulator-Semiconductor Devices},
  series = {physica status solidi a : applications and materials sciences},
  volume    = {216},
  journal   = {physica status solidi a : applications and materials sciences},
  number    = {1900044},
  publisher = {Wiley},
  address   = {Weinheim},
  doi       = {10.1002/pssa.201900044},
  pages     = {1 -- 9},
  year      = {2019},
  language  = {en}
}
@article{BreuerPilasGuthmannetal.2019,
  author    = {Breuer, Lars and Pilas, Johanna and Guthmann, Eric and Sch{\"o}ning, Michael Josef and Thoelen, Ronald and Wagner, Torsten},
  title     = {Towards light-addressable flow control: responsive hydrogels with incorporated graphene oxide as laser-driven actuator structures within microfluidic channels},
  series = {Sensor and Actuators B: Chemical},
  volume    = {288},
  journal   = {Sensor and Actuators B: Chemical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2019.02.086},
  pages     = {579 -- 585},
  year      = {2019},
  language  = {en}
}
@article{DantismRoehlenWagneretal.2019,
  author    = {Dantism, Shahriar and R{\"o}hlen, Desiree and Wagner, Torsten and Wagner, P. and Sch{\"o}ning, Michael Josef},
  title     = {A LAPS-based differential sensor for parallelized metabolism monitoring of various bacteria},
  series = {Sensors},
  volume    = {19},
  journal   = {Sensors},
  number    = {21},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {1424-8220},
  doi       = {10.3390/s19214692},
  pages     = {Artikel 4692},
  year      = {2019},
  abstract  = {Monitoring the cellular metabolism of bacteria in (bio)fermentation processes is crucial to control and steer them, and to prevent undesired disturbances linked to metabolically inactive microorganisms. In this context, cell-based biosensors can play an important role to improve the quality and increase the yield of such processes. This work describes the simultaneous analysis of the metabolic behavior of three different types of bacteria by means of a differential light-addressable potentiometric sensor (LAPS) set-up. The study includes Lactobacillus brevis, Corynebacterium glutamicum, and Escherichia coli, which are often applied in fermentation processes in bioreactors. Differential measurements were carried out to compensate undesirable influences such as sensor signal drift, and pH value variation during the measurements. Furthermore, calibration curves of the cellular metabolism were established as a function of the glucose concentration or cell number variation with all three model microorganisms. In this context, simultaneous (bio)sensing with the multi-organism LAPS-based set-up can open new possibilities for a cost-effective, rapid detection of the extracellular acidification of bacteria on a single sensor chip. It can be applied to evaluate the metabolic response of bacteria populations in a (bio)fermentation process, for instance, in the biogas fermentation process.},
  language  = {en}
}
@article{KarschuckFilipovBollellaetal.2019,
  author    = {Karschuck, T. L. and Filipov, Y. and Bollella, P. and Sch{\"o}ning, Michael Josef and Katz, E.},
  title     = {Not-XOR (NXOR) logic gate based on an enzyme-catalyzed reaction},
  series = {International Journal of Unconventional Computing},
  volume    = {14},
  journal   = {International Journal of Unconventional Computing},
  number    = {3-4},
  publisher = {Old City Publishing},
  address   = {Philadelphia},
  issn      = {1548-7199},
  pages     = {235 -- 242},
  year      = {2019},
  abstract  = {Enzyme-catalyzed reactions have been designed to mimic various Boolean logic gates in the general framework of unconventional biomolecular computing. While some of the logic gates, particularly OR, AND, are easy to realize with biocatalytic reactions and have been reported in numerous publications, some other, like NXOR, are very challenging and have not been realized yet with enzyme reactions. The paper reports on a novel approach to mimicking the NXOR logic gate using the bell-shaped enzyme activity dependent on pH values. Shifting pH from the optimum value to the acidic or basic values by using acid or base inputs (meaning 1,0 and 0,1 inputs) inhibits the enzyme reaction, while keeping the optimum pH (assuming 0,0 and 1,1 input combinations) preserves a high enzyme activity. The challenging part of the present approach is the selection of an enzyme with a well-demonstrated bell-shape activity dependence on the pH value. While many enzymes can satisfy this condition, we selected pyrroloquinoline quinone (PQQ)-dependent glucose dehydrogenase as this enzyme has the optimum pH center-located on the pH scale allowing the enzyme activity change by the acidic and basic pH shift from the optimum value corresponding to the highest activity. The present NXOR gate is added to the biomolecular "toolbox" as a new example of Boolean logic gates based on enzyme reactions.},
  language  = {en}
}
@article{MolinnusBegingLowisetal.2020,
  author    = {Molinnus, Denise and Beging, Stefan and Lowis, Carsten and Sch{\"o}ning, Michael Josef},
  title     = {Towards a multi-enzyme capacitive field-effect biosensor by comparative study of drop-coating and nano-spotting technique},
  series = {Sensors},
  volume    = {20},
  journal   = {Sensors},
  number    = {17},
  publisher = {MDPI},
  address   = {Basel},
  isbn      = {1424-8220},
  doi       = {10.3390/s20174924},
  pages     = {Artikel 4942},
  year      = {2020},
  abstract  = {Multi-enzyme immobilization onto a capacitive field-effect biosensor by nano-spotting technique is presented. The nano-spotting technique allows to immobilize different enzymes simultaneously on the sensor surface with high spatial resolution without additional photolithographical patterning. The amount of applied enzymatic cocktail on the sensor surface can be tailored. Capacitive electrolyte-insulator-semiconductor (EIS) field-effect sensors with Ta2O5 as pH-sensitive transducer layer have been chosen to immobilize the three different (pL droplets) enzymes penicillinase, urease, and glucose oxidase. Nano-spotting immobilization is compared to conventional drop-coating method by defining different geometrical layouts on the sensor surface (fully, half-, and quarter-spotted). The drop diameter is varying between 84 µm and 102 µm, depending on the number of applied drops (1 to 4) per spot. For multi-analyte detection, penicillinase and urease are simultaneously nano-spotted on the EIS sensor. Sensor characterization was performed by C/V (capacitance/voltage) and ConCap (constant capacitance) measurements. Average penicillin, glucose, and urea sensitivities for the spotted enzymes were 81.7 mV/dec, 40.5 mV/dec, and 68.9 mV/dec, respectively.},
  language  = {en}
}
@book{YoshinobuSchoening2020,
  author    = {Yoshinobu, Tatsuo and Sch{\"o}ning, Michael Josef},
  title     = {Light-addressing and chemical imaging technologies for electrochemical sensing},
  editor    = {Yoshinobu, Tatsuo and Sch{\"o}ning, Michael Josef},
  publisher = {MDPI},
  address   = {Basel},
  isbn      = {978-3-03943-029-1},
  doi       = {10.3390/books978-3-03943-029-1},
  pages     = {122 Pages},
  year      = {2020},
  language  = {en}
}
@article{SousaSiqueiraVerciketal.2017,
  author    = {Sousa, Marcos A. M. and Siqueira, Jose R. Jr. and Vercik, Andres and Sch{\"o}ning, Michael Josef and Oliveira, Osvaldo N. Jr.},
  title     = {Determining the optimized layer-by-layer film architecture with dendrimer/carbon nanotubes for field-effect sensors},
  series = {IEEE Sensors Journal},
  volume    = {17},
  journal   = {IEEE Sensors Journal},
  number    = {6},
  publisher = {IEEE},
  address   = {New York},
  issn      = {1558-1748},
  doi       = {10.1109/JSEN.2017.2653238},
  pages     = {1735 -- 1740},
  year      = {2017},
  abstract  = {The capacitive electrolyte-insulator-semiconductor (EIS) structure is a typical device based on a field-effect sensor platform. With a simple silicon-based structure, EIS have been useful for several sensing applications, especially with incorporation of nanostructured films to modulate the ionic transport and the flat-band potential. In this paper, we report on ion transport and changes in flat-band potential in EIS sensors made with layer-by-layer films containing poly(amidoamine) (PAMAM) dendrimer and single-walled carbon nanotubes (SWNTs) adsorbed on p-Si/SiO 2 /Ta 2 O 5 chips with an Al ohmic contact. The impedance spectra were fitted using an equivalent circuit model, from which we could determine parameters such as the double-layer capacitance. This capacitance decreased with the number of bilayers owing to space charge accumulated at the electrolyte-insulator interface, up to three PAMAM/SWNTs bilayers, after which it stabilized. The charge-transfer resistance was also minimum for three bilayers, thus indicating that this is the ideal architecture for an optimized EIS performance. The understanding of the influence of nanostructures and the fine control of operation parameters pave the way for optimizing the design and performance of new EIS sensors.},
  language  = {en}
}
@article{DantismRoehlenDahmenetal.2020,
  author    = {Dantism, Shahriar and R{\"o}hlen, Desiree and Dahmen, Markus and Wagner, Torsten and Wagner, Patrick and Sch{\"o}ning, Michael Josef},
  title     = {LAPS-based monitoring of metabolic responses of bacterial cultures in a paper fermentation broth},
  series = {Sensors and Actuators B: Chemical},
  volume    = {320},
  journal   = {Sensors and Actuators B: Chemical},
  number    = {Art. 128232},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2020.128232},
  year      = {2020},
  abstract  = {As an alternative renewable energy source, methane production in biogas plants is gaining more and more attention. Biomass in a bioreactor contains different types of microorganisms, which should be considered in terms of process-stability control. Metabolically inactive microorganisms within the fermentation process can lead to undesirable, time-consuming and cost-intensive interventions. Hence, monitoring of the cellular metabolism of bacterial populations in a fermentation broth is crucial to improve the biogas production, operation efficiency, and sustainability. In this work, the extracellular acidification of bacteria in a paper-fermentation broth is monitored after glucose uptake, utilizing a differential light-addressable potentiometric sensor (LAPS) system. The LAPS system is loaded with three different model microorganisms (Escherichia coli, Corynebacterium glutamicum, and Lactobacillus brevis) and the effect of the fermentation broth at different process stages on the metabolism of these bacteria is studied. In this way, different signal patterns related to the metabolic response of microorganisms can be identified. By means of calibration curves after glucose uptake, the overall extracellular acidification of bacterial populations within the fermentation process can be evaluated.},
  language  = {en}
}
@article{WeldenSchoeningWagneretal.2020,
  author    = {Welden, Rene and Sch{\"o}ning, Michael Josef and Wagner, Patrick H. and Wagner, Torsten},
  title     = {Light-Addressable Electrodes for Dynamic and Flexible Addressing of Biological Systems and Electrochemical Reactions},
  series = {Sensors},
  volume    = {20},
  journal   = {Sensors},
  number    = {6},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {1424-8220},
  doi       = {10.3390/s20061680},
  pages     = {Artikel 1680},
  year      = {2020},
  abstract  = {In this review article, we are going to present an overview on possible applications of light-addressable electrodes (LAE) as actuator/manipulation devices besides classical electrode structures. For LAEs, the electrode material consists of a semiconductor. Illumination with a light source with the appropiate wavelength leads to the generation of electron-hole pairs which can be utilized for further photoelectrochemical reaction. Due to recent progress in light-projection technologies, highly dynamic and flexible illumination patterns can be generated, opening new possibilities for light-addressable electrodes. A short introduction on semiconductor-electrolyte interfaces with light stimulation is given together with electrode-design approaches. Towards applications, the stimulation of cells with different electrode materials and fabrication designs is explained, followed by analyte-manipulation strategies and spatially resolved photoelectrochemical deposition of different material types.},
  language  = {en}
}
@article{JildehKirchnerOberlaenderetal.2020,
  author    = {Jildeh, Zaid B. and Kirchner, Patrick and Oberl{\"a}nder, Jan and Vahidpour, Farnoosh and Wagner, Patrick H. and Sch{\"o}ning, Michael Josef},
  title     = {Development of a package-sterilization process for aseptic filling machines: A numerical approach and validation for surface treatment with hydrogen peroxide},
  series = {Sensor and Actuators A: Physical},
  volume    = {303},
  journal   = {Sensor and Actuators A: Physical},
  number    = {111691},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0924-4247},
  doi       = {10.1016/j.sna.2019.111691},
  year      = {2020},
  abstract  = {Within the present work a sterilization process by a heated gas mixture that contains hydrogen peroxide (H₂O₂) is validated by experiments and numerical modeling techniques. The operational parameters that affect the sterilization efficacy are described alongside the two modes of sterilization: gaseous and condensed H₂O₂. Measurements with a previously developed H₂O₂ gas sensor are carried out to validate the applied H₂O₂ gas concentration during sterilization. We performed microbiological tests at different H₂O₂ gas concentrations by applying an end-point method to carrier strips, which contain different inoculation loads of Geobacillus stearothermophilus spores. The analysis of the sterilization process of a pharmaceutical glass vial is performed by numerical modeling. The numerical model combines heat- and advection-diffusion mass transfer with vapor-pressure equations to predict the location of condensate formation and the concentration of H₂O₂ at the packaging surfaces by changing the gas temperature. For a sterilization process of 0.7 s, a H₂O₂ gas concentration above 4\% v/v is required to reach a log-count reduction above six. The numerical results showed the location of H₂O₂ condensate formation, which decreases with increasing sterilant-gas temperature. The model can be transferred to different gas nozzle- and packaging geometries to assure the absence of H₂O₂ residues.},
  language  = {en}
}
@article{DantismTakenagaWagneretal.2017,
  author    = {Dantism, Shahriar and Takenaga, Shoko and Wagner, Torsten and Wagner, Patrick and Sch{\"o}ning, Michael Josef},
  title     = {Differential imaging of the metabolism of bacteria and eukaryotic cells based on light-addressable potentiometric sensors},
  series = {Electrochimica Acta},
  volume    = {246},
  journal   = {Electrochimica Acta},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0013-4686},
  doi       = {10.1016/j.electacta.2017.05.196},
  pages     = {234 -- 241},
  year      = {2017},
  abstract  = {A light-addressable potentiometric sensor (LAPS) is a field-effect-based potentiometric sensor with an electrolyte/insulator/semiconductor (EIS) structure, which is able to monitor analyte concentrations of (bio-)chemical species in aqueous solutions in a spatially resolved way. Therefore, it is also an appropriate tool to record 2D-chemical images of concentration variations on the sensor surface. In the present work, two differential, LAPS-based measurement principles are introduced to determine the metabolic activity of Escherichia coli (E. coli) K12 and Chinese hamster ovary (CHO) cells as test microorganisms. Hereby, we focus on i) the determination of the extracellular acidification rate (ΔpH/min) after adding glucose solutions to the cell suspensions; and ii) recording the amplitude increase of the photocurrent (Iph) related to the produced acids from E. coli K12 bacteria and CHO cells on the sensor surface by 2D-chemical imaging. For this purpose, 3D-printed multi-chamber structures were developed and mounted on the planar sensor-chip surface to define four independent compartments, enabling differential measurements with varying cell concentrations. The differential concept allows eliminating unwanted drift effects and, with the four-chamber structures, measurements on the different cell concentrations were performed simultaneously, thus reducing also the overall measuring time.},
  language  = {en}
}
@article{JildehKirchnerOberlaenderetal.2017,
  author    = {Jildeh, Zaid B. and Kirchner, Patrick and Oberl{\"a}nder, Jan and Kremers, Alexander and Wagner, Torsten and Wagner, Patrick H. and Sch{\"o}ning, Michael Josef},
  title     = {FEM-based modeling of a calorimetric gas sensor for hydrogen peroxide monitoring},
  series = {physica status solidi a : applications and materials sciences},
  journal   = {physica status solidi a : applications and materials sciences},
  number    = {Early View},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1862-6319},
  doi       = {10.1002/pssa.201600912},
  year      = {2017},
  abstract  = {A physically coupled finite element method (FEM) model is developed to study the response behavior of a calorimetric gas sensor. The modeled sensor serves as a monitoring device of the concentration of gaseous hydrogen peroxide (H2 O2) in a high temperature mixture stream in aseptic sterilization processes. The principle of operation of a calorimetric H2 O2 sensor is analyzed and the results of the numerical model have been validated by using previously published sensor experiments. The deviation in the results between the FEM model and experimental data are presented and discussed.},
  language  = {en}
}
@article{MiyamotoHayashiSakamotoetal.2017,
  author    = {Miyamoto, Ko-ichiro and Hayashi, Kosuke and Sakamoto, Azuma and Werner, Frederik and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {A high-Q resonance-mode measurement of EIS capacitive sensor by elimination of series resistance},
  series = {Sensor and Actuators B: Chemical},
  volume    = {248},
  journal   = {Sensor and Actuators B: Chemical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2017.03.002},
  pages     = {1006 -- 1010},
  year      = {2017},
  abstract  = {An EIS capacitive sensor is a semiconductor-based potentiometric sensor, which is sensitive to the ion concentration or pH value of the solution in contact with the sensing surface. To detect a small change in the ion concentration or pH, a small capacitance change must be detected. Recently, a resonance-mode measurement was proposed, in which an inductor was connected to the EIS capacitive sensor and the resonant frequency was correlated with the pH value. In this study, the Q factor of the resonant circuit was enhanced by canceling the internal resistance of the reference electrode and the internal resistance of the inductor coil with the help of a bypass capacitor and a negative impedance converter, respectively. 1\% variation of the signal in the developed system corresponded to a pH change of 3.93 mpH, which was about 1/12 of the conventional method, suggesting a better performance in detection of a small pH change.},
  language  = {en}
}
@article{WernerMiyamotoWagneretal.2017,
  author    = {Werner, Frederik and Miyamoto, Ko-ichiro and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {Lateral resolution enhancement of pulse-driven light-addressable potentiometric sensor},
  series = {Sensor and Actuators B: Chemical},
  volume    = {248},
  journal   = {Sensor and Actuators B: Chemical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2017.02.057},
  pages     = {961 -- 965},
  year      = {2017},
  abstract  = {To study chemical and biological processes, spatially resolved determination of the concentrations of one or more analyte species is of distinct interest. With a light-addressable potentiometric sensor (LAPS), chemical images can be created, which visualize the concentration distribution above the sensor plate. One important challenge is to achieve a good lateral resolution in order to detect events that take place in a small and limited region. LAPS utilizes a focused light spot to address the measurement region. By moving this light spot along the semiconductor sensor plate, the concentration distribution can be observed. In this study, we show that utilizing a pulse as light excitation instead of a traditionally used continuously modulated light excitation, the lateral resolution can be improved by a factor of 6 or more.},
  language  = {en}
}
@article{SchollMoraisGabrieletal.2017,
  author    = {Scholl, Fabio and Morais, Paulo and Gabriel, Rayla and Sch{\"o}ning, Michael Josef and Siqueira, Jose Roberto, Jr. and Caseli, Luciano},
  title     = {Carbon nanotubes arranged as smart interfaces in lipid Langmuir-Blodgett films enhancing the enzymatic properties of penicillinase for biosensing applications},
  series = {Applied Materials \& Interfaces},
  volume    = {9},
  journal   = {Applied Materials \& Interfaces},
  number    = {36},
  publisher = {ACS},
  address   = {Washington},
  issn      = {1944-8252},
  doi       = {10.1021/acsami.7b08095},
  pages     = {31054 -- 31066},
  year      = {2017},
  abstract  = {In this paper, carbon nanotubes (CNTs) were incorporated in penicillinase-phospholipid Langmuir and Langmuir-Blodgett (LB) films to enhance the enzyme catalytic properties. Adsorption of the penicillinase and CNTs at dimyristoylphosphatidic acid (DMPA) monolayers at the air-water interface was investigated by surface pressure-area isotherms, vibrational spectroscopy, and Brewster angle microscopy. The floating monolayers were transferred to solid supports through the LB technique, forming mixed DMPA-CNTs-PEN films, which were investigated by quartz crystal microbalance, vibrational spectroscopy, and atomic force microscopy. Enzyme activity was studied with UV-vis spectroscopy and the feasibility of the supramolecular device nanostructured as ultrathin films were essayed in a capacitive electrolyte-insulator-semiconductor (EIS) sensor device. The presence of CNTs in the enzyme-lipid LB film not only tuned the catalytic activity of penicillinase but also helped conserve its enzyme activity after weeks, showing increased values of activity. Viability as penicillin sensor was demonstrated with capacitance/voltage and constant capacitance measurements, exhibiting regular and distinctive output signals over all concentrations used in this work. These results may be related not only to the nanostructured system provided by the film, but also to the synergism between the compounds on the active layer, leading to a surface morphology that allowed a fast analyte diffusion because of an adequate molecular accommodation, which also preserved the penicillinase activity. This work therefore demonstrates the feasibility of employing LB films composed of lipids, CNTs, and enzymes as EIS devices for biosensing applications.},
  language  = {en}
}
@inproceedings{MiyamotoSutoWerneretal.2017,
  author    = {Miyamoto, Ko-ichiro and Suto, Takeyuki and Werner, Frederik and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {Restraining the Diffusion of Photocarriers to Improve the Spatial Resolution of the Chemical Imaging Sensor},
  series = {MDPI Proceedings},
  volume    = {1},
  booktitle = {MDPI Proceedings},
  number    = {4},
  doi       = {10.3390/proceedings1040477},
  pages     = {4 Seiten},
  year      = {2017},
  language  = {en}
}
@article{FigueroaMirandaFengShiuetal.2018,
  author    = {Figueroa-Miranda, Gabriela and Feng, Lingyan and Shiu, Simon Chi-Chin and Dirkzwager, Roderick Marshall and Cheung, Yee-Wai and Tanner, Julian Alexander and Sch{\"o}ning, Michael Josef and Offenh{\"a}usser, Andreas and Mayer, Dirk},
  title     = {Aptamer-based electrochemical biosensor for highly sensitive and selective malaria detection with adjustable dynamic response range and reusability},
  series = {Sensor and Actuators B: Chemical},
  volume    = {255},
  journal   = {Sensor and Actuators B: Chemical},
  number    = {P1},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2017.07.117},
  pages     = {235 -- 243},
  year      = {2018},
  abstract  = {Malaria infection remains a significant risk for much of the population of tropical and subtropical areas, particularly in developing countries. Therefore, it is of high importance to develop sensitive, accurate and inexpensive malaria diagnosis tests. Here, we present a novel aptamer-based electrochemical biosensor (aptasensor) for malaria detection by impedance spectroscopy, through the specific recognition between a highly discriminatory DNA aptamer and its target Plasmodium falciparum lactate dehydrogenase (PfLDH). Interestingly, due to the isoelectric point (pI) of PfLDH, the aptasensor response showed an adjustable detection range based on the different protein net-charge at variable pH environments. The specific aptamer recognition allows sensitive protein detection with an expanded detection range and a low detection limit, as well as a high specificity for PfLDH compared to analogous proteins. The specific feasibility of the aptasensor is further demonstrated by detection of the target PfLDH in human serum. Furthermore, the aptasensor can be easily regenerated and thus applied for multiple usages. The robustness, sensitivity, and reusability of the presented aptasensor make it a promising candidate for point-of-care diagnostic systems.},
  language  = {en}
}
@article{MoraisGomesSilvaetal.2017,
  author    = {Morais, Paulo V. and Gomes, Vanderley F., Jr. and Silva, Anielle C. A. and Dantas, Noelio O. and Sch{\"o}ning, Michael Josef and Siqueira, Jos{\´e} R., Jr.},
  title     = {Nanofilm of ZnO nanocrystals/carbon nanotubes as biocompatible layer for enzymatic biosensors in capacitive field-effect devices},
  series = {Journal of Materials Science},
  volume    = {52},
  journal   = {Journal of Materials Science},
  number    = {20},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1573-4803},
  doi       = {10.1007/s10853-017-1369-y},
  pages     = {12314 -- 12325},
  year      = {2017},
  abstract  = {The incorporation of nanomaterials that are biocompatible with different types of biological compounds has allowed the development of a new generation of biosensors applied especially in the biomedical field. In particular, the integration of film-based nanomaterials employed in field-effect devices can be interesting to develop biosensors with enhanced properties. In this paper, we studied the fabrication of sensitive nanofilms combining ZnO nanocrystals and carbon nanotubes (CNTs), prepared by means of the layer-by-layer (LbL) technique, in a capacitive electrolyte-insulator-semiconductor (EIS) structure for detecting glucose and urea. The ZnO nanocrystals were incorporated in a polymeric matrix of poly(allylamine) hydrochloride (PAH), and arranged with multi-walled CNTs in a LbL PAH-ZnO/CNTs film architecture onto EIS chips. The electrochemical characterizations were performed by capacitance-voltage and constant capacitance measurements, while the morphology of the films was characterized by atomic force microscopy. The enzymes glucose oxidase and urease were immobilized on film's surface for detection of glucose and urea, respectively. In order to obtain glucose and urea biosensors with optimized amount of sensitive films, we investigated the ideal number of bilayers for each detection system. The glucose biosensor showed better sensitivity and output signal for an LbL PAH-ZnO/CNTs nanofilm with 10 bilayers. On the other hand, the urea biosensor presented enhanced properties even for the first bilayer, exhibiting high sensitivity and output signal. The presence of the LbL PAH-ZnO/CNTs films led to biosensors with better sensitivity and enhanced response signal, demonstrating that the adequate use of nanostructured films is feasible for proof-of-concept biosensors with improved properties that may be employed for biomedical applications.},
  language  = {en}
}
@article{RoehlenPilasSchoeningetal.2017,
  author    = {R{\"o}hlen, Desiree and Pilas, Johanna and Sch{\"o}ning, Michael Josef and Selmer, Thorsten},
  title     = {Development of an amperometric biosensor platform for the combined determination of l-Malic, Fumaric, and l-Aspartic acid},
  series = {Applied Biochemistry and Biotechnology},
  volume    = {183},
  journal   = {Applied Biochemistry and Biotechnology},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1559-0291},
  doi       = {10.1007/s12010-017-2578-1},
  pages     = {566 -- 581},
  year      = {2017},
  abstract  = {Three amperometric biosensors have been developed for the detection of L-malic acid, fumaric acid, and L -aspartic acid, all based on the combination of a malate-specific dehydrogenase (MDH, EC 1.1.1.37) and diaphorase (DIA, EC 1.8.1.4). The stepwise expansion of the malate platform with the enzymes fumarate hydratase (FH, EC 4.2.1.2) and aspartate ammonia-lyase (ASPA, EC 4.3.1.1) resulted in multi-enzyme reaction cascades and, thus, augmentation of the substrate spectrum of the sensors. Electrochemical measurements were carried out in presence of the cofactor β-nicotinamide adenine dinucleotide (NAD+) and the redox mediator hexacyanoferrate (III) (HCFIII). The amperometric detection is mediated by oxidation of hexacyanoferrate (II) (HCFII) at an applied potential of + 0.3 V vs. Ag/AgCl. For each biosensor, optimum working conditions were defined by adjustment of cofactor concentrations, buffer pH, and immobilization procedure. Under these improved conditions, amperometric responses were linear up to 3.0 mM for L-malate and fumarate, respectively, with a corresponding sensitivity of 0.7 μA mM-1 (L-malate biosensor) and 0.4 μA mM-1 (fumarate biosensor). The L-aspartate detection system displayed a linear range of 1.0-10.0 mM with a sensitivity of 0.09 μA mM-1. The sensor characteristics suggest that the developed platform provides a promising method for the detection and differentiation of the three substrates.},
  language  = {en}
}
@inproceedings{BreuerGuthmannSchoeningetal.2017,
  author    = {Breuer, Lars and Guthmann, Eric and Sch{\"o}ning, Michael Josef and Thoelen, Ronald and Wagner, Torsten},
  title     = {Light-Stimulated Hydrogels with Incorporated Graphene Oxide as Actuator Material for Flow Control in Microfluidic Applications},
  series = {Proceedings Eurosensors 2017 Conference, Paris, France, 3-6 September 2017},
  booktitle = {Proceedings Eurosensors 2017 Conference, Paris, France, 3-6 September 2017},
  doi       = {10.3390/proceedings1040524},
  pages     = {1 -- 4},
  year      = {2017},
  language  = {en}
}
@article{BreuerMangSchoeningetal.2017,
  author    = {Breuer, Lars and Mang, Thomas and Sch{\"o}ning, Michael Josef and Thoelen, Ronald and Wagner, Torsten},
  title     = {Investigation of the spatial resolution of a laser-based stimulation process for light-addressable hydrogels with incorporated graphene oxide by means of IR thermography},
  series = {Sensors and Actuators A: Physical},
  volume    = {268},
  journal   = {Sensors and Actuators A: Physical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0924-4247},
  doi       = {10.1016/j.sna.2017.11.031},
  pages     = {126 -- 132},
  year      = {2017},
  language  = {en}
}