@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} } @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} } @article{SchoeningPoghossianYoshinobuetal.2001, author = {Sch{\"o}ning, Michael Josef and Poghossian, Arshak and Yoshinobu, Tatsuo and L{\"u}th, Hans}, title = {Semiconductor-based field-effect structures for chemical sensing}, pages = {188 -- 198}, year = {2001}, 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{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{MiyamotoWagnerYoshinobuetal.2011, author = {Miyamoto, Ko-ichiro and Wagner, Torsten and Yoshinobu, Tatsuo and Kanoh, Shin`ichiro and Sch{\"o}ning, Michael Josef}, title = {Phase-mode operation of FDM-LAPS}, series = {Sensor letters}, volume = {9}, journal = {Sensor letters}, number = {2}, publisher = {American Scientific Publishers}, address = {Stevenson Ranch, Calif.}, isbn = {1546-1971}, pages = {691 -- 694}, year = {2011}, language = {en} } @article{MiyamotoWagnerYoshinobuetal.2011, author = {Miyamoto, Ko-ichiro and Wagner, Torsten and Yoshinobu, Tatsuo and Kanoh, Shin`ichiro and Sch{\"o}ning, Michael Josef}, title = {Phase-mode LAPS and its application to chemical imaging}, series = {Sensors and Actuators B: Chemical. 154 (2011), H. 1}, journal = {Sensors and Actuators B: Chemical. 154 (2011), H. 1}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {1873-3077}, pages = {28 -- 32}, year = {2011}, language = {en} } @article{PoghossianYoshinobuSimonisetal.2001, author = {Poghossian, Arshak and Yoshinobu, Tatsuo and Simonis, A. and Ecken, H. and L{\"u}th, Hans and Sch{\"o}ning, Michael Josef}, title = {Penicillin detection by means of field-effect based sensors: EnFET, capacitive EIS sensor or LAPS?}, series = {Sensors and Actuators B. 78 (2001), H. 1-3}, journal = {Sensors and Actuators B. 78 (2001), H. 1-3}, isbn = {0925-4005}, pages = {237 -- 242}, year = {2001}, 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 = {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{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{MiyamotoKanekoMatsuoetal.2010, author = {Miyamoto, Ko-ichiro and Kaneko, Kazumi and Matsuo, Akira and Wagner, Torsten and Kanoh, Shin`ichiro and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo}, title = {Miniaturized chemical imaging sensor system using an OLED display panel}, series = {Procedia Engineering. 5 (2010)}, journal = {Procedia Engineering. 5 (2010)}, isbn = {1877-7058}, pages = {516 -- 519}, year = {2010}, language = {en} } @article{MiyamotoKanekoMatsuoetal.2012, author = {Miyamoto, Ko-ichiro and Kaneko, Kazumi and Matsuo, Akira and Wagner, Torsten and Kanoh, Shin{\´i}chiro and Sch{\"o}ning, Michael Josef and Yoshinobu, Tatsuo}, title = {Miniaturized chemical imaging sensor system using an OLED display panel}, 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.2011.02.029}, pages = {82 -- 87}, year = {2012}, abstract = {The chemical imaging sensor is a semiconductor-based chemical sensor that can visualize the two-dimensional distribution of specific ions or molecules in the solution. In this study, we developed a miniaturized chemical imaging sensor system with an OLED display panel as a light source that scans the sensor plate. In the proposed configuration, the display panel is placed directly below the sensor plate and illuminates the back surface. The measured area defined by illumination can be arbitrarily customized to fit the size and the shape of the sample to be measured. The waveform of the generated photocurrent, the current-voltage characteristics and the pH sensitivity were investigated and pH imaging with this miniaturized system was demonstrated.}, 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{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} } @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{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{YoshinobuSchoening2021, author = {Yoshinobu, Tatsuo and Sch{\"o}ning, Michael Josef}, title = {Light-addressable potentiometric sensors (LAPS) for cell monitoring and biosensing}, series = {Current Opinion in Electrochemistry}, journal = {Current Opinion in Electrochemistry}, number = {In Press, Journal Pre-proof}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2451-9103}, doi = {10.1016/j.coelec.2021.100727}, year = {2021}, 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{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{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} }