@article{OezsoyluKizildagSchoeningetal.2020,
  author    = {{\"O}zsoylu, Dua and Kizildag, Sefa and Sch{\"o}ning, Michael Josef and Wagner, Torsten},
  title     = {Differential chemical imaging of extracellular acidification within microfluidic channels using a plasma-functionalized light-addressable potentiometric sensor (LAPS)},
  series = {Physics in Medicine},
  volume    = {10},
  journal   = {Physics in Medicine},
  number    = {100030},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {2352-4510},
  doi       = {10.1016/j.phmed.2020.100030},
  pages     = {8},
  year      = {2020},
  abstract  = {Extracellular acidification is a basic indicator for alterations in two vital metabolic pathways: glycolysis and cellular respiration. Measuring these alterations by monitoring extracellular acidification using cell-based biosensors such as LAPS plays an important role in studying these pathways whose disorders are associated with numerous diseases including cancer. However, the surface of the biosensors must be specially tailored to ensure high cell compatibility so that cells can represent more in vivo-like behavior, which is critical to gain more realistic in vitro results from the analyses, e.g., drug discovery experiments. In this work, O2 plasma patterning on the LAPS surface is studied to enhance surface features of the sensor chip, e.g., wettability and biofunctionality. The surface treated with O2 plasma for 30 s exhibits enhanced cytocompatibility for adherent CHO-K1 cells, which promotes cell spreading and proliferation. The plasma-modified LAPS chip is then integrated into a microfluidic system, which provides two identical channels to facilitate differential measurements of the extracellular acidification of CHO-K1 cells. To the best of our knowledge, it is the first time that extracellular acidification within microfluidic channels is quantitatively visualized as differential (bio-)chemical images.},
  language  = {en}
}
@article{OezsoyluKizildagSchoeningetal.2019,
  author    = {{\"O}zsoylu, Dua and Kizildag, Sefa and Sch{\"o}ning, Michael Josef and Wagner, Torsten},
  title     = {Effect of plasma treatment on the sensor properties of a light-addressable potentiometric sensor (LAPS)},
  series = {physica status solidi a : applications and materials sciences},
  volume    = {216},
  journal   = {physica status solidi a : applications and materials sciences},
  number    = {20},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1862-6319},
  doi       = {10.1002/pssa.201900259},
  pages     = {8 Seiten},
  year      = {2019},
  abstract  = {A light-addressable potentiometric sensor (LAPS) is a field-effect-based (bio-) chemical sensor, in which a desired sensing area on the sensor surface can be defined by illumination. Light addressability can be used to visualize the concentration and spatial distribution of the target molecules, e.g., H+ ions. This unique feature has great potential for the label-free imaging of the metabolic activity of living organisms. The cultivation of those organisms needs specially tailored surface properties of the sensor. O2 plasma treatment is an attractive and promising tool for rapid surface engineering. However, the potential impacts of the technique are carefully investigated for the sensors that suffer from plasma-induced damage. Herein, a LAPS with a Ta2O5 pH-sensitive surface is successfully patterned by plasma treatment, and its effects are investigated by contact angle and scanning LAPS measurements. The plasma duration of 30 s (30 W) is found to be the threshold value, where excessive wettability begins. Furthermore, this treatment approach causes moderate plasma-induced damage, which can be reduced by thermal annealing (10 min at 300 °C). These findings provide a useful guideline to support future studies, where the LAPS surface is desired to be more hydrophilic by O2 plasma treatment.},
  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}
}
@inproceedings{YoshinobuMiyamotoWagneretal.2012,
  author    = {Yoshinobu, Tatsuo and Miyamoto, Ko-Ichiro and Wagner, Torsten and Sch{\"o}ning, Michael Josef},
  title     = {Miniaturized and high-speed chemical imaging systems},
  series = {Nano-Biomedical Engineering 2012. Proceedings of the Tohoku University Global Centre of Excellence Programme, Sakura Hall, Tohoku University, Sendai Japan, 5 - 6 March 2012},
  booktitle = {Nano-Biomedical Engineering 2012. Proceedings of the Tohoku University Global Centre of Excellence Programme, Sakura Hall, Tohoku University, Sendai Japan, 5 - 6 March 2012},
  editor    = {Yamaguchi, Takami},
  publisher = {World Scientific},
  address   = {Singapur},
  doi       = {10.1142/9781848169067_0045},
  pages     = {386 -- 395},
  year      = {2012},
  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{YoshinobuMiyamotoWagneretal.2024,
  author    = {Yoshinobu, Tatsuo and Miyamoto, Ko-ichiro and Wagner, Torsten and Sch{\"o}ning, Michael Josef},
  title     = {Field-effect sensors combined with the scanned light pulse technique: from artificial olfactory images to chemical imaging technologies},
  series = {Chemosensors},
  volume    = {12},
  journal   = {Chemosensors},
  number    = {2},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2227-9040},
  doi       = {10.3390/chemosensors12020020},
  pages     = {Artikel 20},
  year      = {2024},
  abstract  = {The artificial olfactory image was proposed by Lundstr{\"o}m et al. in 1991 as a new strategy for an electronic nose system which generated a two-dimensional mapping to be interpreted as a fingerprint of the detected gas species. The potential distribution generated by the catalytic metals integrated into a semiconductor field-effect structure was read as a photocurrent signal generated by scanning light pulses. The impact of the proposed technology spread beyond gas sensing, inspiring the development of various imaging modalities based on the light addressing of field-effect structures to obtain spatial maps of pH distribution, ions, molecules, and impedance, and these modalities have been applied in both biological and non-biological systems. These light-addressing technologies have been further developed to realize the position control of a faradaic current on the electrode surface for localized electrochemical reactions and amperometric measurements, as well as the actuation of liquids in microfluidic devices.},
  language  = {en}
}
@incollection{YoshinobuKrauseMiyamotoetal.2018,
  author    = {Yoshinobu, Tatsuo and Krause, Steffi and Miyamoto, Ko-ichiro and Werner, Frederik and Poghossian, Arshak and Wagner, Torsten and Sch{\"o}ning, Michael Josef},
  title     = {(Bio-)chemical Sensing and Imaging by LAPS and SPIM},
  series = {Label-free biosensing: advanced materials, devices and applications},
  booktitle = {Label-free biosensing: advanced materials, devices and applications},
  publisher = {Springer},
  address   = {Cham},
  isbn      = {978-3-319-75219-8},
  pages     = {103 -- 132},
  year      = {2018},
  abstract  = {The light-addressable potentiometric sensor (LAPS) and scanning photo-induced impedance microscopy (SPIM) are two closely related methods to visualise the distributions of chemical species and impedance, respectively, at the interface between the sensing surface and the sample solution. They both have the same field-effect structure based on a semiconductor, which allows spatially resolved and label-free measurement of chemical species and impedance in the form of a photocurrent signal generated by a scanning light beam. In this article, the principles and various operation modes of LAPS and SPIM, functionalisation of the sensing surface for measuring various species, LAPS-based chemical imaging and high-resolution sensors based on silicon-on-sapphire substrates are described and discussed, focusing on their technical details and prospective applications.},
  language  = {en}
}
@article{YoshinobuIwasakiUietal.2005,
  author    = {Yoshinobu, T. and Iwasaki, H. and Ui, Y. and Furuichi, K. and Ermelenko, Y. and Mourzina, Y. and Wagner, Torsten and N{\"a}ther, Niko and Sch{\"o}ning, Michael Josef},
  title     = {The light-addressable potentiometric sensor for multi-ion sensing and imaging},
  series = {Methods. 37 (2005), H. 1},
  journal   = {Methods. 37 (2005), H. 1},
  isbn      = {1046-2023},
  pages     = {99 -- 102},
  year      = {2005},
  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}
}
@article{WernerWagnerYoshinobuetal.2013,
  author    = {Werner, Frederik and Wagner, Torsten and Yoshinobu, Tatsuo and Keusgen, Michael and Sch{\"o}ning, Michael Josef},
  title     = {Frequency behaviour of light-addressable potentiometric sensors},
  series = {Physica Status Solidi (A)},
  volume    = {210},
  journal   = {Physica Status Solidi (A)},
  number    = {5},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1521-396X ; 0031-8965},
  doi       = {10.1002/pssa.201200929},
  pages     = {884 -- 891},
  year      = {2013},
  abstract  = {Light-addressable potentiometric sensors (LAPS) are semiconductor-based potentiometric sensors, with the advantage to detect the concentration of a chemical species in a liquid solution above the sensor surface in a spatially resolved manner. The addressing is achieved by a modulated and focused light source illuminating the semiconductor and generating a concentration-depending photocurrent. This work introduces a LAPS set-up that is able to monitor the electrical impedance in addition to the photocurrent. The impedance spectra of a LAPS structure, with and without illumination, as well as the frequency behaviour of the LAPS measurement are investigated. The measurements are supported by electrical equivalent circuits to explain the impedance and the LAPS-frequency behaviour. The work investigates the influence of different parameters on the frequency behaviour of the LAPS. Furthermore, the phase shift of the photocurrent, the influence of the surface potential as well as the changes of the sensor impedance will be discussed.},
  language  = {en}
}
@article{WernerWagnerMiyamotoetal.2012,
  author    = {Werner, Frederik and Wagner, Torsten and Miyamoto, Ko-ichiro and Yoshinobu, Tatsuo and Sch{\"o}ning, Michael Josef},
  title     = {High speed and high resolution chemical imaging based on a new type of OLED-LAPS set-up},
  series = {Sensors and Actuators B: Chemical},
  volume    = {175},
  journal   = {Sensors and Actuators B: Chemical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2011.12.102},
  pages     = {118 -- 122},
  year      = {2012},
  abstract  = {Light-addressable potentiometric sensors (LAPS) are field-effect-based sensors. A modulated light source is used to define the particular measurement spot to perform spatially resolved measurements of chemical species and to generate chemical images. In this work, an organic-LED (OLED) display has been chosen as a light source. This allows high measurement resolution and miniaturisation of the system. A new developed driving method for the OLED display optimised for LAPS-based measurements is demonstrated. The new method enables to define modulation frequencies between 1 kHz and 16 kHz and hence, reduces the measurement time of a chemical image by a factor of 40 compared to the traditional addressing of an OLED display.},
  language  = {en}
}
@article{WernerWagnerMiyamotoetal.2011,
  author    = {Werner, Frederik and Wagner, Torsten and Miyamoto, Ko-ichiro and Yoshinobu, Tatsuo and Sch{\"o}ning, Michael Josef},
  title     = {High speed and high resolution chemical imaging based on a new type of OLED-LAPS set-up},
  series = {Procedia Engineering. 25 (2011)},
  journal   = {Procedia Engineering. 25 (2011)},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {1877-7058},
  pages     = {346 -- 349},
  year      = {2011},
  language  = {en}
}
@article{WernerSchusserSpalthahnetal.2011,
  author    = {Werner, Frederik and Schusser, Sebastian and Spalthahn, Heiko and Wagner, Torsten and Yoshinobu, Tatsuo and Sch{\"o}ning, Michael Josef},
  title     = {Field-programmable gate array based controller for multi spot light-addressable potentiometric sensors with integrated signal correction mode},
  series = {Electrochimica Acta},
  volume    = {56},
  journal   = {Electrochimica Acta},
  number    = {26},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0013-4686},
  doi       = {10.1016/j.electacta.2011.03.012},
  pages     = {9656 -- 9660},
  year      = {2011},
  abstract  = {A light-addressable potentiometric sensor (LAPS) can measure the concentration of one or several analytes at the sensor surface simultaneously in a spatially resolved manner. A modulated light pointer stimulates the semiconductor structure at the area of interest and a responding photocurrent can be read out. By simultaneous stimulation of several areas with light pointers of different modulation frequencies, the read out can be performed at the same time. With the new proposed controller electronic based on a field-programmable gate array (FPGA), it is possible to control the modulation frequencies, phase shifts, and light brightness of multiple light pointers independently and simultaneously. Thus, it is possible to investigate the frequency response of the sensor, and to examine the analyte concentration by the determination of the surface potential with the help of current/voltage curves and phase/voltage curves. Additionally, the ability to individually change the light intensities of each light pointer is used to perform signal correction.},
  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{WernerKrumbeSchumacheretal.2011,
  author    = {Werner, Frederik and Krumbe, Christoph and Schumacher, Katharina and Groebel, Simone and Spelthahn, Heiko and Stellberg, Michael and Wagner, Torsten and Yoshinobu, Tatsuo and Selmer, Thorsten and Keusgen, Michael and Baumann, Marcus and Sch{\"o}ning, Michael Josef},
  title     = {Determination of the extracellular acidification of Escherichia coli by a light-addressable potentiometric sensor},
  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     = {1340 -- 1344},
  year      = {2011},
  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{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{WeldenNagamineKomesuWagneretal.2021,
  author    = {Welden, Rene and Nagamine Komesu, Cindy A. and Wagner, Patrick H. and Sch{\"o}ning, Michael Josef and Wagner, Torsten},
  title     = {Photoelectrochemical enzymatic penicillin biosensor: A proof-of-concept experiment},
  series = {Electrochemical Science Advances},
  volume    = {2},
  journal   = {Electrochemical Science Advances},
  number    = {4},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {2698-5977},
  doi       = {10.1002/elsa.202100131},
  pages     = {1 -- 5},
  year      = {2021},
  abstract  = {Photoelectrochemical (PEC) biosensors are a rather novel type of biosensors thatutilizelighttoprovideinformationaboutthecompositionofananalyte,enablinglight-controlled multi-analyte measurements. For enzymatic PEC biosensors,amperometric detection principles are already known in the literature. In con-trast, there is only a little information on H+-ion sensitive PEC biosensors. Inthis work, we demonstrate the detection of H+ions emerged by H+-generatingenzymes, exemplarily demonstrated with penicillinase as a model enzyme on atitanium dioxide photoanode. First, we describe the pH sensitivity of the sensorand study possible photoelectrocatalytic reactions with penicillin. Second, weshow the enzymatic PEC detection of penicillin.},
  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}
}
@article{WagnerYoshinobuRaoetal.2005,
  author    = {Wagner, Torsten and Yoshinobu, T. and Rao, C. and Otto, R. and Sch{\"o}ning, Michael Josef},
  title     = {„All-in-one" solid-state device based on a lightaddressable potentiometric sensor platform},
  series = {Transducers '05 : the 13th International Conference on Solid-State Sensors, Actuators and Microsystems ; Seoul, Korea, [June 5 - 9, 2005] ; digest of technical papers / sponsored by Korean Sensors Society. Technical co-sponsors: IEEE Electron Devices Society},
  journal   = {Transducers '05 : the 13th International Conference on Solid-State Sensors, Actuators and Microsystems ; Seoul, Korea, [June 5 - 9, 2005] ; digest of technical papers / sponsored by Korean Sensors Society. Technical co-sponsors: IEEE Electron Devices Society},
  publisher = {IEEE Operations Center},
  address   = {Piscataway, NJ},
  isbn      = {0-7803-83995-6},
  pages     = {1872 -- 1875},
  year      = {2005},
  language  = {en}
}
@article{WagnerWernerMiyamotoetal.2012,
  author    = {Wagner, Torsten and Werner, Frederik and Miyamoto, Ko-Ichiro and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {Development and characterisation of a compact light-addressable potentiometric sensor (LAPS) based on the digital light processing (DLP) technology for flexible chemical imaging},
  series = {Sensors and Actuators B: Chemical},
  volume    = {170},
  journal   = {Sensors and Actuators B: Chemical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2010.12.003},
  pages     = {34 -- 39},
  year      = {2012},
  abstract  = {Chemical imaging systems allow the visualisation of the distribution of chemical species on the sensor surface. This work represents a new flexible approach to read out light-addressable potentiometric sensors (LAPS) with the help of a digital light processing (DLP) set-up. The DLP, known well for video projectors, consists of a mirror-array MEMS device, which allows fast and flexible generation of light patterns. With the help of these light patterns, the sensor surface of the LAPS device can be addressed. The DLP approach has several advantages compared to conventional LAPS set-ups, e.g., the spot size and the shape of the light pointer can be changed easily and no mechanical movement is necessary, which reduces the size of the set-up and increases the stability and speed of the measurement. In addition, the modulation frequency and intensity of the light beam are important parameters of the LAPS set-up. Within this work, the authors will discuss two different ways of light modulation by the DLP set-up, investigate the influence of different modulation frequencies and different light intensities as well as demonstrate the scanning capabilities of the new set-up by pH mapping on the sensor surface.},
  language  = {en}
}
@article{WagnerWernerMiyamotoetal.2011,
  author    = {Wagner, Torsten and Werner, Frederik and Miyamoto, Ko-Ichiro and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {A high-density multi-point LAPS set-up using a VCSEL array and FPGA control},
  series = {Sensors and Actuators B: Chemical. 154 (2011), H. 2},
  journal   = {Sensors and Actuators B: Chemical. 154 (2011), H. 2},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {1873-3077},
  pages     = {124 -- 128},
  year      = {2011},
  language  = {en}
}
@article{WagnerWernerMiyamotoetal.2010,
  author    = {Wagner, Torsten and Werner, Frederik and Miyamoto, Ko-ichiro and Ackermann, Hans-Josef and Yoshinobu, Tatsuo and Sch{\"o}ning, Michael Josef},
  title     = {FPGA-based LAPS device for the flexible design of sensing sites on functional interfaces},
  series = {Physica Status Solidi (A). 207 (2010), H. 4},
  journal   = {Physica Status Solidi (A). 207 (2010), H. 4},
  isbn      = {1862-6300},
  pages     = {844 -- 849},
  year      = {2010},
  language  = {en}
}
@article{WagnerWernerMiyamotoetal.2009,
  author    = {Wagner, Torsten and Werner, Frederik and Miyamoto, K. and Sch{\"o}ning, Michael Josef and Yoshinobu, T.},
  title     = {A high-density multi-point LAPS set-up using a VCSEL array and FPGA control},
  series = {Procedia Chemistry. 1 (2009), H. 1},
  journal   = {Procedia Chemistry. 1 (2009), H. 1},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {1876-6196},
  pages     = {1483 -- 1486},
  year      = {2009},
  language  = {en}
}
@article{WagnerVornholtWerneretal.2016,
  author    = {Wagner, Torsten and Vornholt, Wolfgang and Werner, Frederik and Yoshinobu, Tatsuo and Miyamoto, Ko-Ichiro and Keusgen, Michael and Sch{\"o}ning, Michael Josef},
  title     = {Light-addressable potentiometric sensor (LAPS) combined with magnetic beads for pharmaceutical screening},
  series = {Physics in medicine},
  volume    = {2016},
  journal   = {Physics in medicine},
  number    = {1},
  issn      = {2352-4510},
  doi       = {10.1016/j.phmed.2016.03.001},
  pages     = {2 -- 7},
  year      = {2016},
  abstract  = {The light-addressable potentiometric sensor (LAPS) has the unique feature to address different regions of a sensor surface without the need of complex structures. Measurements at different locations on the sensor surface can be performed in a common analyte solution, which distinctly simplifies the fluidic set-up. However, the measurement in a single analyte chamber prevents the application of different drugs or different concentrations of a drug to each measurement spot at the same time as in the case of multi-reservoir-based set-ups. In this work, the authors designed a LAPS-based set-up for cell culture screening that utilises magnetic beads loaded with the endotoxin (lipopolysaccharides, LPS), to generate a spatially distributed gradient of analyte concentration. Different external magnetic fields can be adjusted to move the magnetic beads loaded with a specific drug within the measurement cell. By recording the metabolic activities of a cell layer cultured on top of the LAPS surface, this work shows the possibility to apply different concentrations of a sample along the LAPS measurement spots within a common analyte solution.},
  language  = {en}
}
@article{WagnerShigiaharaMiyamotoetal.2012,
  author    = {Wagner, Torsten and Shigiahara, N. and Miyamoto, K. and Suzurikawa, J. and Finger, F. and Sch{\"o}ning, Michael Josef and Yoshinobu, T.},
  title     = {Light-addressable Potentiometric Sensors and Light-addressable Electrodes as a Combined Sensor-and-manipulator Microsystem with High Flexibility},
  series = {Procedia Engineering},
  journal   = {Procedia Engineering},
  number    = {47},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1877-7058},
  doi       = {10.1016/j.proeng.2012.09.290},
  pages     = {890 -- 893},
  year      = {2012},
  abstract  = {This work describes the novel combination of the light-addressable electrode (LAE) and the light-addressable potentiometric sensor (LAPS) into a microsystem set-up. Both the LAE as well as the LAPS shares the principle of addressing the active spot by means of a light beam. This enables both systems to manipulate resp. to detect an analyte with a high spatial resolution. Hence, combining both principles into a single set-up enables the active stimulation e.g., by means of electrolysis and a simultaneous observation e.g., the response of an entrapped biological cell by detection of extracellular pH changes. The work will describe the principles of both technologies and the necessary steps to integrate them into a single set-up. Furthermore, examples of application and operation of such systems will be presented.},
  language  = {en}
}
@article{WagnerSchoeningOttoetal.2004,
  author    = {Wagner, Torsten and Sch{\"o}ning, Michael Josef and Otto, R. and Yoshinobu, T.},
  title     = {A handheld 16 channel pen-type LAPS as a platform for (bio-)electrochemical sensing},
  series = {Biomedizinische Technik. 49 (2004), H. 2},
  journal   = {Biomedizinische Technik. 49 (2004), H. 2},
  isbn      = {0932-4666},
  pages     = {996 -- 997},
  year      = {2004},
  language  = {en}
}
@article{WagnerSchoening2007,
  author    = {Wagner, Torsten and Sch{\"o}ning, Michael Josef},
  title     = {Light-addressable potentiometric sensors (LAPS): recent trends and applications},
  series = {Electrochemical sensor analysis / edited by S. Alegret ...},
  journal   = {Electrochemical sensor analysis / edited by S. Alegret ...},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {978-0-444-53053-0},
  pages     = {87 -- 128},
  year      = {2007},
  language  = {en}
}
@inproceedings{WagnerSchoening2006,
  author    = {Wagner, Torsten and Sch{\"o}ning, Michael Josef},
  title     = {Preface of the Special Issue of I3S 2005 in J{\"u}lich (Germany)},
  url       = {http://nbn-resolving.de/urn:nbn:de:hbz:a96-opus-1365},
  year      = {2006},
  abstract  = {International Symposium on Sensor Science, I3S 2005 <3; 2005; Juelich, Germany> In: Sensors 2006, 6, 260-261 ISSN 1424-8220},
  subject      = {Biosensor},
  language  = {en}
}
@article{WagnerRaoKloocketal.2006,
  author    = {Wagner, Torsten and Rao, C. and Kloock, Joachim P. and Yoshinobu, T. and Otto, R. and Keusgen, M. and Sch{\"o}ning, Michael Josef},
  title     = {"LAPS Card"—A novel chip card-based light-addressable potentiometric sensor (LAPS)},
  series = {Sensors and Actuators B: Chemical. 118 (2006), H. 1-2},
  journal   = {Sensors and Actuators B: Chemical. 118 (2006), H. 1-2},
  isbn      = {0925-4005},
  pages     = {33 -- 40},
  year      = {2006},
  language  = {en}
}
@article{WagnerMolinaYoshinobuetal.2007,
  author    = {Wagner, Torsten and Molina, Roberto and Yoshinobu, Tatsuo and Kloock, Joachim P. and Biselli, Manfred and Canzoneri, Michele and Schnitzler, Thomas and Sch{\"o}ning, Michael Josef},
  title     = {Handheld multi-channel LAPS device as a transducer platform for possible biological and chemical multi-sensor applications},
  series = {Electrochimica Acta. 53 (2007), H. 2},
  journal   = {Electrochimica Acta. 53 (2007), H. 2},
  isbn      = {0013-4686},
  pages     = {305 -- 311},
  year      = {2007},
  language  = {en}
}
@article{WagnerMolinaBisellietal.2007,
  author    = {Wagner, Torsten and Molina, R. and Biselli, Manfred and Canzoneri, Michele and Schnitzler, Thomas and Yoshinobu, Tatsuo and Sch{\"o}ning, Michael Josef},
  title     = {A light-addressable potentiometric sensor system for fast, simultaneous and spatial detection of the metabolic activity of biological cells},
  series = {Transducers '07 Eurosensors XXI : digest of technical papers ; the14th International Conference on Solid-State Sensors, Actuators and Microsystems, June 10-14, 2007, Lyon, France / Gilles Delapierre (Ed.)},
  journal   = {Transducers '07 Eurosensors XXI : digest of technical papers ; the14th International Conference on Solid-State Sensors, Actuators and Microsystems, June 10-14, 2007, Lyon, France / Gilles Delapierre (Ed.)},
  publisher = {IEEE},
  address   = {Piscataway},
  isbn      = {1-4244-0841-5},
  pages     = {1107 -- 1110},
  year      = {2007},
  language  = {en}
}
@article{WagnerMiyamotoShigiharaetal.2011,
  author    = {Wagner, Torsten and Miyamoto, Ko-ichiro and Shigihara, Noriko and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {Microfluidic systems with free definable sensor spots by an integrated light-addressable potentiometric sensor},
  series = {Procedia Engineering. 25 (2011)},
  journal   = {Procedia Engineering. 25 (2011)},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {1877-7058},
  pages     = {791 -- 794},
  year      = {2011},
  language  = {en}
}
@article{WagnerMiyamotoSchoeningetal.2010,
  author    = {Wagner, Torsten and Miyamoto, Ko-ichiro and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {Novel combination of digital light processing (DLP) and light-addressable potentiometric sensors (LAPS) for flexible chemical imaging},
  series = {Procedia Engineering. 5 (2010)},
  journal   = {Procedia Engineering. 5 (2010)},
  isbn      = {1877-7058},
  pages     = {520 -- 523},
  year      = {2010},
  language  = {en}
}
@article{WagnerMiyamotoWerneretal.2011,
  author    = {Wagner, Torsten and Miyamoto, K. and Werner, Frederik and Sch{\"o}ning, Michael Josef and Yoshinobu, T.},
  title     = {Flexible electrochemical imaging with "zoom-in" functionality by using a new type of light-addressable potentiometric sensor},
  publisher = {IEEE},
  address   = {New York},
  pages     = {2133 -- 2135},
  year      = {2011},
  language  = {en}
}
@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}
}
@article{WagnerMarisAckermannetal.2007,
  author    = {Wagner, Torsten and Maris, Rob J. and Ackermann, Hans-Josef and Otto, Ralph and Beging, Stefan and Poghossian, Arshak and Sch{\"o}ning, Michael Josef},
  title     = {Handheld measurement device for field-effect sensor structures: Practical evaluation and limitations},
  series = {Sensors and Actuators B: Chemical . 127 (2007), H. 1},
  journal   = {Sensors and Actuators B: Chemical . 127 (2007), H. 1},
  isbn      = {0925-4005},
  pages     = {217 -- 223},
  year      = {2007},
  language  = {en}
}
@article{WagnerKloockSchoening2007,
  author    = {Wagner, Torsten and Kloock, Joachim P. and Sch{\"o}ning, Michael Josef},
  title     = {Determination of cadmium concentration and pH value in aqueous solutions by means of a handheld light-addressable potentiometric sensor (LAPS) device},
  series = {Electrochemical sensor analysis / edited by S. Alegret ...},
  journal   = {Electrochemical sensor analysis / edited by S. Alegret ...},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {978-0-444-53133-9},
  pages     = {e35 -- e44},
  year      = {2007},
  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}
}
@article{SchoeningWagnerWangetal.2005,
  author    = {Sch{\"o}ning, Michael Josef and Wagner, Torsten and Wang, C. and Otto, R. and Yoshinobu, T.},
  title     = {Development of a handheld 16 channel pen-type LAPS for electrochemical sensing},
  series = {Sensors and Actuators B. 108 (2005)},
  journal   = {Sensors and Actuators B. 108 (2005)},
  isbn      = {0925-4005},
  pages     = {808 -- 814},
  year      = {2005},
  language  = {en}
}
@article{SchoeningWagnerWangetal.2004,
  author    = {Sch{\"o}ning, Michael Josef and Wagner, Torsten and Wang, C. and Otto, R. and Yoshinobu, T.},
  title     = {Development of a handheld 16 channel pen-type LAPS for electrochemical sensing},
  series = {Technical digest of the 10th International Meeting on Chemical Sensors, July 11 - 14, 2004, Tsukuba, Japan / Japan Association of Chemical Sensors},
  journal   = {Technical digest of the 10th International Meeting on Chemical Sensors, July 11 - 14, 2004, Tsukuba, Japan / Japan Association of Chemical Sensors},
  publisher = {Japan Association of Chemical Sensors},
  address   = {Fukuoka},
  pages     = {136 -- 137},
  year      = {2004},
  language  = {en}
}
@incollection{SchoeningWagnerPoghossianetal.2018,
  author    = {Sch{\"o}ning, Michael Josef and Wagner, Torsten and Poghossian, Arshak and Miyamoto, K.I. and Werner, C.F. and Krause, S. and Yoshinobu, T.},
  title     = {Light-addressable potentiometric sensors for (bio-)chemical sensing and imaging},
  series = {Encyclopedia of Interfacial Chemistry: Surface Science and Electrochemistry. Vol. 7},
  booktitle = {Encyclopedia of Interfacial Chemistry: Surface Science and Electrochemistry. Vol. 7},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {9780128097397},
  pages     = {295 -- 308},
  year      = {2018},
  language  = {en}
}
@inproceedings{SchoeningAbouzarWagneretal.2006,
  author    = {Sch{\"o}ning, Michael Josef and Abouzar, Maryam H. and Wagner, Torsten and N{\"a}ther, Niko and Rolka, David and Yoshinobu, Tatsuo and Kloock, Joachim P. and Turek, Monika and Ingebrandt, Sven and Poghossian, Arshak},
  title     = {A semiconductor-based field-effect platform for (bio-)chemical and physical sensors: From capacitive EIS sensors and LAPS over ISFETs to nano-scale devices},
  series = {MRS Proceedings},
  booktitle = {MRS Proceedings},
  doi       = {10.1557/PROC-0952-F08-02},
  pages     = {1 -- 9},
  year      = {2006},
  language  = {en}
}
@article{ReisertGeisslerFlorkeetal.2011,
  author    = {Reisert, Steffen and Geissler, H. and Florke, R. and Wagner, P. and Wagner, Torsten and Sch{\"o}ning, Michael Josef},
  title     = {Controlling aseptic sterilization processes by means of a multi-sensor system},
  publisher = {IEEE},
  address   = {New York},
  pages     = {18 -- 22},
  year      = {2011},
  language  = {en}
}
@article{PoghossianWernerBuniatyanetal.2017,
  author    = {Poghossian, Arshak and Werner, Frederik and Buniatyan, V. V. and Wagner, Torsten and Miamoto, K. and Yoshinobu, T. and Sch{\"o}ning, Michael Josef},
  title     = {Towards addressability of light-addressable potentiometric sensors: Shunting effect of non-illuminated region and cross-talk},
  series = {Sensor and Actuators B: Chemical},
  journal   = {Sensor and Actuators B: Chemical},
  number    = {244},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2017.01.047},
  pages     = {1071 -- 1079},
  year      = {2017},
  abstract  = {The LAPS (light-addressable potentiometric sensor) platform is one of the most attractive approaches for chemical and biological sensing with many applications ranging from pH and ion/analyte concentration measurements up to cell metabolism detection and chemical imaging. However, although it is generally accepted that LAPS measurements are spatially resolved, the light-addressability feature of LAPS devices has not been discussed in detail so far. In this work, an extended electrical equivalent-circuit model of the LAPS has been presented, which takes into account possible cross-talk effects due to the capacitive coupling of the non-illuminated region. A shunting effect of the non-illuminated area on the measured photocurrent and addressability of LAPS devices has been studied. It has been shown, that the measured photocurrent will be determined not only by the local interfacial potential in the illuminated region but also by possible interfacial potential changes in the non-illuminated region, yielding cross-talk effects. These findings were supported by the experimental investigations of a penicillin-sensitive multi-spot LAPS and a metal-insulator-semiconductor LAPS as model systems.},
  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{MuschallikMolinnusBongaertsetal.2017,
  author    = {Muschallik, Lukas and Molinnus, Denise and Bongaerts, Johannes and Pohl, Martina and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Siegert, Petra and Selmer, Thorsten},
  title     = {(R,R)-Butane-2,3-diol Dehydrogenase from Bacillus clausii DSM 8716T: Cloning and Expression of the bdhA-Gene, and Initial Characterization of Enzyme},
  series = {Journal of Biotechnology},
  volume    = {258},
  journal   = {Journal of Biotechnology},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0168-1656},
  doi       = {10.1016/j.jbiotec.2017.07.020},
  pages     = {41 -- 50},
  year      = {2017},
  abstract  = {The gene encoding a putative (R,R)-butane-2,3-diol dehydrogenase (bdhA) from Bacillus clausii DSM 8716T was isolated, sequenced and expressed in Escherichia coli. The amino acid sequence of the encoded protein is only distantly related to previously studied enzymes (identity 33-43\%) and exhibited some uncharted peculiarities. An N-terminally StrepII-tagged enzyme variant was purified and initially characterized. The isolated enzyme catalyzed the (R)-specific oxidation of (R,R)- and meso-butane-2,3-diol to (R)- and (S)-acetoin with specific activities of 12 U/mg and 23 U/mg, respectively. Likewise, racemic acetoin was reduced with a specific activity of up to 115 U/mg yielding a mixture of (R,R)- and meso-butane-2,3-diol, while the enzyme reduced butane-2,3-dione (Vmax 74 U/mg) solely to (R,R)-butane-2,3-diol via (R)-acetoin. For these reactions only activity with the co-substrates NADH/NAD+ was observed. The enzyme accepted a selection of vicinal diketones, α-hydroxy ketones and vicinal diols as alternative substrates. Although the physiological function of the enzyme in B. clausii remains elusive, the data presented herein clearly demonstrates that the encoded enzyme is a genuine (R,R)-butane-2,3-diol dehydrogenase with potential for applications in biocatalysis and sensor development.},
  language  = {en}
}
@article{MolinnusMuschallikGonzalezetal.2018,
  author    = {Molinnus, Denise and Muschallik, Lukas and Gonzalez, Laura Osorio and Bongaerts, Johannes and Wagner, Torsten and Selmer, Thorsten and Siegert, Petra and Keusgen, Michael and Sch{\"o}ning, Michael Josef},
  title     = {Development and characterization of a field-effect biosensor for the detection of acetoin},
  series = {Biosensors and Bioelectronics},
  volume    = {115},
  journal   = {Biosensors and Bioelectronics},
  publisher = {Elsevier},
  address   = {Amsterdam},
  doi       = {10.1016/j.bios.2018.05.023},
  pages     = {1 -- 6},
  year      = {2018},
  abstract  = {A capacitive electrolyte-insulator-semiconductor (EIS) field-effect biosensor for acetoin detection has been presented for the first time. The EIS sensor consists of a layer structure of Al/p-Si/SiO₂/Ta₂O₅/enzyme acetoin reductase. The enzyme, also referred to as butane-2,3-diol dehydrogenase from B. clausii DSM 8716T, has been recently characterized. The enzyme catalyzes the (R)-specific reduction of racemic acetoin to (R,R)- and meso-butane-2,3-diol, respectively. Two different enzyme immobilization strategies (cross-linking by using glutaraldehyde and adsorption) have been studied. Typical biosensor parameters such as optimal pH working range, sensitivity, hysteresis, linear concentration range and long-term stability have been examined by means of constant-capacitance (ConCap) mode measurements. Furthermore, preliminary experiments have been successfully carried out for the detection of acetoin in diluted white wine samples.},
  language  = {en}
}
@article{MiyamotoSekiSutoetal.2018,
  author    = {Miyamoto, Koichiro and Seki, Kosuke and Suto, Takeyuki and Werner, Frederik and Wagner, Torsten and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo},
  title     = {Improved spatial resolution of the chemical imaging sensor with a hybrid illumination that suppresses lateral diffusion of photocarriers},
  series = {Sensor and Actuators B: Chemical},
  volume    = {273},
  journal   = {Sensor and Actuators B: Chemical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2018.07.016},
  pages     = {1328 -- 1333},
  year      = {2018},
  abstract  = {The chemical imaging sensor is a semiconductor-based chemical sensor capable of visualizing pH and ion distributions. The spatial resolution depends on the lateral diffusion of photocarriers generated by illumination of the semiconductor substrate. In this study, two types of optical setups, one based on a bundle of optical fibers and the other based on a binocular tube head, were developed to project a hybrid illumination of a modulated light beam and a ring-shaped constant illumination onto the sensor plate. An improved spatial resolution was realized by the ring-shaped constant illumination, which suppressed lateral diffusion of photocarriers by enhanced recombination due to the increased carrier concentration.},
  language  = {en}
}
@article{MiyamotoYoshidaSakaietal.2011,
  author    = {Miyamoto, Ko-ichiro and Yoshida, Midori and Sakai, Taito and Matsuzaka, Atsushi and Wagner, Torsten and Kanoh, Sanoh and Yoshinobu, Tatsuo and Sch{\"o}ning, Michael Josef},
  title     = {Differential setup of light-addressable potentiometric sensor with an enzyme reactor in a flow channel},
  series = {Japanese Journal of Applied Physics. 50 (2011)},
  journal   = {Japanese Journal of Applied Physics. 50 (2011)},
  publisher = {Japan Society of Applied Physics},
  address   = {Bristol},
  isbn      = {0021-4922},
  pages     = {04DL08-1 -- 04DL08-5},
  year      = {2011},
  language  = {en}
}