@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} } @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{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{PoghossianYoshinobuSimonisetal.2000, author = {Poghossian, Arshak and Yoshinobu, T. and Simonis, A. and Ecken, H. and L{\"u}th, H. and Sch{\"o}ning, Michael Josef}, title = {Penicillin detection by means of field-effect based sensors: EnFET, capacitive EIS sensor or LAPS?}, series = {Proceedings : Copenhagen, Denmark, 27 - 30 August 2000 / [ed.: R. de Reus ...]}, journal = {Proceedings : Copenhagen, Denmark, 27 - 30 August 2000 / [ed.: R. de Reus ...]}, publisher = {MIC, Mikroelektronik Centret}, address = {Lyngby, Denmark}, isbn = {87-89935-50-0}, pages = {27 -- 30}, year = {2000}, language = {en} } @article{YoshinobuEckenPoghossianetal.2001, author = {Yoshinobu, T. and Ecken, H. and Poghossian, Arshak and Simonis, A. and Iwasaki, H. and L{\"u}th, H. and Sch{\"o}ning, Michael Josef}, title = {Constant-current-mode LAPS (CLAPS) for the detection of penicillin}, series = {Electroanalysis. 13 (2001), H. 8-9}, journal = {Electroanalysis. 13 (2001), H. 8-9}, isbn = {1040-0397}, pages = {733 -- 736}, year = {2001}, language = {en} } @article{YoshinobuEckenPoghossianetal.2001, author = {Yoshinobu, T. and Ecken, H. and Poghossian, Arshak and L{\"u}th, H. and Iwasaki, H. and Sch{\"o}ning, Michael Josef}, title = {Alternative sensor materials for light-addressable potentiometric sensors}, series = {Sensors and Actuators B. 76 (2001), H. 1-3}, journal = {Sensors and Actuators B. 76 (2001), H. 1-3}, isbn = {0925-4005}, pages = {388 -- 392}, year = {2001}, language = {en} }