TY - JOUR A1 - Siqueira, Jose R. A1 - Werner, Frederik A1 - Bäcker, Matthias A1 - Poghossian, Arshak A1 - Zucolotto, Valtencir A1 - Oliveira, Osvaldo N. Jr. A1 - Schöning, Michael Josef T1 - Layer-by-Layer Assembly of Carbon Nanotubes Incorporated in Light-Addressable Potentiometric Sensors JF - Journal of Physical Chemistry C. 113 (2009), H. 33 Y1 - 2009 SN - 1932-7455 SP - 14765 EP - 14770 PB - American Chemical Society CY - Washington, DC ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Brinkmann, D. A1 - Rolka, David A1 - Demuth, C. A1 - Poghossian, Arshak T1 - CIP (cleaning-in-place) suitable “non-glass” pH sensor based on a Ta2O5-gate EIS structure JF - Sensors and Actuators B: Chemical. 111-112 (2005) Y1 - 2005 SN - 0925-4005 N1 - Eurosensors XVIII 2004 - The 18th European Conference on Solid-State Transducers SP - 423 EP - 429 ER - TY - JOUR A1 - Poghossian, Arshak A1 - Werner, Frederik A1 - Buniatyan, V. V. A1 - Wagner, Torsten A1 - Miamoto, K. A1 - Yoshinobu, T. A1 - Schöning, Michael Josef T1 - Towards addressability of light-addressable potentiometric sensors: Shunting effect of non-illuminated region and cross-talk JF - Sensor and Actuators B: Chemical N2 - 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. Y1 - 2017 U6 - https://doi.org/10.1016/j.snb.2017.01.047 SN - 0925-4005 IS - 244 SP - 1071 EP - 1079 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Poghossian, Arshak T1 - Detection of charged macromolecules by means of field-effect devices (FEDs): possibilities and limitations JF - Electrochemical sensors, biosensors and their biomedical applications / ed. by Xueji Zhang ... Y1 - 2008 SN - 978-0-12-373738-0 SP - 187 EP - 212 PB - Elsevier Acad. Press CY - Amsterdam ER - TY - JOUR A1 - Molinnus, Denise A1 - Bäcker, Matthias A1 - Iken, Heiko A1 - Poghossian, Arshak A1 - Keusgen, Michael A1 - Schöning, Michael Josef T1 - Concept for a biomolecular logic chip with an integrated sensor and actuator function JF - Physica status solidi (a) N2 - A concept for a new generation of an integrated multi-functional biosensor/actuator system is developed, which is based on biomolecular logic principles. Such a system is expected to be able to detect multiple biochemical input signals simultaneously and in real-time and convert them into electrical output signals with logical operations such as OR, AND, etc. The system can be designed as a closed-loop drug release device triggered by an enzyme logic gate, while the release of the drug induced by the actuator at the required dosage and timing will be controlled by an additional drug sensor. Thus, the system could help to make an accurate and specific diagnosis. The presented concept is exemplarily demonstrated by using an enzyme logic gate based on a glucose/glucose oxidase system, a temperature-responsive hydrogel mimicking the actuator function and an insulin (drug) sensor. In this work, the results of functional testing of individual amperometric glucose and insulin sensors as well as an impedimetric sensor for the detection of the hydrogel swelling/shrinking are presented. Y1 - 2015 U6 - https://doi.org/10.1002/pssa.201431913 SN - 1862-6319 VL - 212 IS - 6 SP - 1382 EP - 1388 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Christiaens, P. A1 - Abouzar, Maryam H. A1 - Poghossian, Arshak A1 - Wagner, Torsten A1 - Bijnens, N. A1 - Williams, O. A. A1 - Daenen, M. A1 - Haenen, K. A1 - Douthéret, O. A1 - Haen, J. d´ A1 - Mekhalif, Z. A1 - Schöning, Michael Josef A1 - Wagner, P. T1 - pH sensitivity of nanocrystalline diamond films JF - Physica status solidi (A). 204 (2007), H. 9 Y1 - 2007 SN - 0031-8965 SP - 2925 EP - 2930 ER - TY - JOUR A1 - Wu, Chunsheng A1 - Poghossian, Arshak A1 - Bronder, Thomas A1 - Schöning, Michael Josef T1 - Sensing of double-stranded DNA molecules by their intrinsic molecular charge using the light-addressable potentiometric sensor JF - Sensors and Actuators B: Chemical N2 - A multi-spot light-addressable potentiometric sensor (LAPS), which belongs to the family of semiconductor field-effect devices, was applied for label-free detection of double-stranded deoxyribonucleic acid (dsDNA) molecules by their intrinsic molecular charge. To reduce the distance between the DNA charge and sensor surface and thus, to enhance the electrostatic coupling between the dsDNA molecules and the LAPS, the negatively charged dsDNA molecules were electrostatically adsorbed onto the gate surface of the LAPS covered with a positively charged weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)). The surface potential changes in each spot of the LAPS, induced by the layer-by-layer adsorption of a PAH/dsDNA bilayer, were recorded by means of photocurrent-voltage and constant-photocurrent measurements. In addition, the surface morphology of the gate surface before and after consecutive electrostatic adsorption of PAH and dsDNA layers was studied by atomic force microscopy measurements. Moreover, fluorescence microscopy was used to verify the successful adsorption of dsDNA molecules onto the PAH-modified LAPS surface. A high sensor signal of 25 mV was registered after adsorption of 10 nM dsDNA molecules. The lower detection limit is down to 0.1 nM dsDNA. The obtained results demonstrate that the PAH-modified LAPS device provides a convenient and rapid platform for the direct label-free electrical detection of in-solution hybridized dsDNA molecules. KW - Layer-by-layer adsorption KW - Poly(allylamine hydrochloride) KW - Label-free detection KW - DNA biosensor KW - LAPS KW - Field effect Y1 - 2016 U6 - https://doi.org/10.1016/j.snb.2016.02.004 SN - 0925-4005 IS - 229 SP - 506 EP - 512 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Poghossian, Arshak A1 - Schöning, Michael Josef T1 - Label-free sensing of biomolecules with field-effect devices for clinical applications JF - Electroanalysis N2 - Among the variety of transducer concepts proposed for label-free detection of biomolecules, the semiconductor field-effect device (FED) is one of the most attractive platforms. As medical techniques continue to progress towards diagnostic and therapies based on biomarkers, the ability of FEDs for a label-free, fast and real-time detection of multiple pathogenic and physiologically relevant molecules with high specificity and sensitivity offers very promising prospects for their application in point-of-care and personalized medicine for an early diagnosis and treatment of diseases. The presented paper reviews recent advances and current trends in research and development of different FEDs for label-free, direct electrical detection of charged biomolecules by their intrinsic molecular charge. The authors are mainly focusing on the detection of the DNA hybridization event, antibody-antigen affinity reaction as well as clinically relevant biomolecules such as cardiac and cancer biomarkers. Y1 - 2014 U6 - https://doi.org/10.1002/elan.201400073 SN - 1521-4109 (E-Journal); 1040-0397 (Print) VL - 26 IS - 6 SP - 1197 EP - 1213 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Leinhos, Marcel A1 - Schusser, Sebastian A1 - Bäcker, Matthias A1 - Poghossian, Arshak A1 - Schöning, Michael Josef T1 - Micromachined multi-parameter sensor chip for the control of polymer-degradation medium JF - Physica Status Solidi (A) : special issue on engineering and functional interfaces N2 - It is well known that the degradation environment can strongly influence the biodegradability and kinetics of biodegradation processes of polymers. Therefore, besides the monitoring of the degradation process, it is also necessary to control the medium in which the degradation takes place. In this work, a micromachined multi-parameter sensor chip for the control of the polymer-degradation medium has been developed. The chip combines a capacitive field-effect pH sensor, a four-electrode electrolyte-conductivity sensor and a thin-film Pt-temperature sensor. The results of characterization of individual sensors are presented. In addition, the multi-parameter sensor chip together with an impedimetric polymer-degradation sensor was simultaneously characterized in degradation solutions with different pH and electrolyte conductivity. The obtained results demonstrate the feasibility of the multi-parameter sensor chip for the control of the polymer-degradation medium. Y1 - 2014 U6 - https://doi.org/10.1002/pssa.201330364 SN - 1521-396X (E-Journal); 1862-6319 (E-Journal); 0031-8965 (Print); 1862-6300 (Print) VL - 211 IS - 6 SP - 1346 EP - 1351 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Huck, Christina A1 - Poghossian, Arshak A1 - Bäcker, Matthias A1 - Chaudhuri, S. A1 - Zander, W. A1 - Schubert, J. A1 - Begoyan, V. K. A1 - Buniatyan, V. V. A1 - Wagner, P. A1 - Schöning, Michael Josef T1 - Capacitively coupled electrolyte-conductivity sensor based on high-k material of barium strontium titanate JF - Sensors and actuators. B: Chemical Y1 - 2014 U6 - https://doi.org/10.1016/j.snb.2014.02.103 SN - 1873-3077 (E-Journal); 0925-4005 (Print) IS - 198 SP - 102 EP - 109 PB - Elsevier CY - Amsterdam ER -