@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{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{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{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{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{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{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{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{WagnerRaoOttoetal.2005,
  author    = {Wagner, Torsten and Rao, C. and Otto, R. and Yoshinobu, T. and Kloock, Joachim P. and Sch{\"o}ning, Michael Josef},
  title     = {Chipkarten-basierter Multikanal lichtadressierbarer potentiometrischer Sensor f{\"u}r analytische Anwendungen in fl{\"u}ssigen Medien},
  series = {Neue Herausforderungen und Anwendungen in der Sensortechnik : 7. Dresdner Sensor-Symposium ; 12. - 14. Dezember 2005, Dresden / [Forschungsgesellschaft f{\"u}r Messtechnik, Sensorik und Medizintechnik e.V.]. Gerald Gerlach ... (Hg.)},
  journal   = {Neue Herausforderungen und Anwendungen in der Sensortechnik : 7. Dresdner Sensor-Symposium ; 12. - 14. Dezember 2005, Dresden / [Forschungsgesellschaft f{\"u}r Messtechnik, Sensorik und Medizintechnik e.V.]. Gerald Gerlach ... (Hg.)},
  publisher = {TUDpress},
  address   = {Dresden},
  isbn      = {3-938863-29-3},
  pages     = {11 -- 14},
  year      = {2005},
  language  = {de}
}
@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{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{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{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{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{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.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}
}
@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{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}
}
@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{WangKrauseBlocketal.2003,
  author    = {Wang, J. and Krause, R. and Block, K. and Musameh, M. and Mulchandani, A. and Sch{\"o}ning, Michael Josef},
  title     = {Flow injection amperometric detection of OP nerve agents based on organophosphorus-hydrolase biosensor detector},
  series = {Biosensors \& Bioelectronics. 18 (2003), H. 2-3},
  journal   = {Biosensors \& Bioelectronics. 18 (2003), H. 2-3},
  isbn      = {0956-5663},
  pages     = {255 -- 260},
  year      = {2003},
  language  = {en}
}
@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}
}
@inproceedings{WeilPoghossianSchoeningetal.2012,
  author    = {Weil, M. and Poghossian, Arshak and Sch{\"o}ning, Michael Josef and Cherstvy, A.},
  title     = {Electrical monitoring of layer-by-layer adsorption of oppositely charged macromolecules by means of capacitive field-effect devices},
  isbn      = {978-3-9813484-2-2},
  doi       = {10.5162/IMCS2012/P2.5.2},
  pages     = {1575 -- 1578},
  year      = {2012},
  language  = {en}
}
@article{WeldenPoghossianVahidpouretal.2022,
  author    = {Welden, Melanie and Poghossian, Arshak and Vahidpour, Farnoosh and Wendlandt, Tim and Keusgen, Michael and Wege, Christina and Sch{\"o}ning, Michael Josef},
  title     = {Towards multi-analyte detection with field-effect capacitors modified with tobacco mosaic virus bioparticles as enzyme nanocarriers},
  series = {Biosensors},
  volume    = {12},
  journal   = {Biosensors},
  number    = {1},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2079-6374},
  doi       = {10.3390/bios12010043},
  pages     = {Artikel 43},
  year      = {2022},
  abstract  = {Utilizing an appropriate enzyme immobilization strategy is crucial for designing enzyme-based biosensors. Plant virus-like particles represent ideal nanoscaffolds for an extremely dense and precise immobilization of enzymes, due to their regular shape, high surface-to-volume ratio and high density of surface binding sites. In the present work, tobacco mosaic virus (TMV) particles were applied for the co-immobilization of penicillinase and urease onto the gate surface of a field-effect electrolyte-insulator-semiconductor capacitor (EISCAP) with a p-Si-SiO₂-Ta₂O₅ layer structure for the sequential detection of penicillin and urea. The TMV-assisted bi-enzyme EISCAP biosensor exhibited a high urea and penicillin sensitivity of 54 and 85 mV/dec, respectively, in the concentration range of 0.1-3 mM. For comparison, the characteristics of single-enzyme EISCAP biosensors modified with TMV particles immobilized with either penicillinase or urease were also investigated. The surface morphology of the TMV-modified Ta₂O₅-gate was analyzed by scanning electron microscopy. Additionally, the bi-enzyme EISCAP was applied to mimic an XOR (Exclusive OR) enzyme logic gate.},
  language  = {en}
}
@article{WeldenSeverinsPoghossianetal.2022,
  author    = {Welden, Melanie and Severins, Robin and Poghossian, Arshak and Wege, Christina and Bongaerts, Johannes and Siegert, Petra and Keusgen, Michael and Sch{\"o}ning, Michael Josef},
  title     = {Detection of acetoin and diacetyl by a tobacco mosaic virus-assisted field-effect biosensor},
  series = {Chemosensors},
  volume    = {10},
  journal   = {Chemosensors},
  number    = {6},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2227-9040},
  doi       = {10.3390/chemosensors10060218},
  pages     = {Artikel 218},
  year      = {2022},
  abstract  = {Acetoin and diacetyl have a major impact on the flavor of alcoholic beverages such as wine or beer. Therefore, their measurement is important during the fermentation process. Until now, gas chromatographic techniques have typically been applied; however, these require expensive laboratory equipment and trained staff, and do not allow for online monitoring. In this work, a capacitive electrolyte-insulator-semiconductor sensor modified with tobacco mosaic virus (TMV) particles as enzyme nanocarriers for the detection of acetoin and diacetyl is presented. The enzyme acetoin reductase from Alkalihalobacillus clausii DSM 8716ᵀ is immobilized via biotin-streptavidin affinity, binding to the surface of the TMV particles. The TMV-assisted biosensor is electrochemically characterized by means of leakage-current, capacitance-voltage, and constant capacitance measurements. In this paper, the novel biosensor is studied regarding its sensitivity and long-term stability in buffer solution. Moreover, the TMV-assisted capacitive field-effect sensor is applied for the detection of diacetyl for the first time. The measurement of acetoin and diacetyl with the same sensor setup is demonstrated. Finally, the successive detection of acetoin and diacetyl in buffer and in diluted beer is studied by tuning the sensitivity of the biosensor using the pH value of the measurement solution.},
  language  = {en}
}
@inproceedings{WeldenSeverinsPoghossianetal.2022,
  author    = {Welden, Melanie and Severins, Robin and Poghossian, Arshak and Wege, Christina and Siegert, Petra and Keusgen, Michael and Sch{\"o}ning, Michael Josef},
  title     = {Studying the immobilization of acetoin reductase with Tobacco mosaic virus particles on capacitive field-effect sensors},
  series = {2022 IEEE International Symposium on Olfaction and Electronic Nose (ISOEN)},
  booktitle = {2022 IEEE International Symposium on Olfaction and Electronic Nose (ISOEN)},
  publisher = {IEEE},
  isbn      = {978-1-6654-5860-3 (Online)},
  doi       = {10.1109/ISOEN54820.2022.9789657},
  pages     = {4 Seiten},
  year      = {2022},
  abstract  = {A capacitive electrolyte-insulator-semiconductor (EISCAP) biosensor modified with Tobacco mosaic virus (TMV) particles for the detection of acetoin is presented. The enzyme acetoin reductase (AR) was immobilized on the surface of the EISCAP using TMV particles as nanoscaffolds. The study focused on the optimization of the TMV-assisted AR immobilization on the Ta 2 O 5 -gate EISCAP surface. The TMV-assisted acetoin EISCAPs were electrochemically characterized by means of leakage-current, capacitance-voltage, and constant-capacitance measurements. The TMV-modified transducer surface was studied via scanning electron microscopy.},
  language  = {en}
}
@article{WeldenJablonskiWegeetal.2021,
  author    = {Welden, Rene and Jablonski, Melanie and Wege, Christina and Keusgen, Michael and Wagner, Patrick Hermann and Wagner, Torsten and Sch{\"o}ning, Michael Josef},
  title     = {Light-Addressable Actuator-Sensor Platform for Monitoring and Manipulation of pH Gradients in Microfluidics: A Case Study with the Enzyme Penicillinase},
  series = {Biosensors},
  volume    = {11},
  journal   = {Biosensors},
  number    = {6},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2079-6374},
  doi       = {10.3390/bios11060171},
  pages     = {Artikel 171},
  year      = {2021},
  abstract  = {The feasibility of light-addressed detection and manipulation of pH gradients inside an electrochemical microfluidic cell was studied. Local pH changes, induced by a light-addressable electrode (LAE), were detected using a light-addressable potentiometric sensor (LAPS) with different measurement modes representing an actuator-sensor system. Biosensor functionality was examined depending on locally induced pH gradients with the help of the model enzyme penicillinase, which had been immobilized in the microfluidic channel. The surface morphology of the LAE and enzyme-functionalized LAPS was studied by scanning electron microscopy. Furthermore, the penicillin sensitivity of the LAPS inside the microfluidic channel was determined with regard to the analyte's pH influence on the enzymatic reaction rate. In a final experiment, the LAE-controlled pH inhibition of the enzyme activity was monitored by the LAPS.},
  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}
}
@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{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{WendlandtKochBritzetal.2023,
  author    = {Wendlandt, Tim and Koch, Claudia and Britz, Beate and Liedek, Anke and Schmidt, Nora and Werner, Stefan and Gleba, Yuri and Vahidpour, Farnoosh and Welden, Melanie and Poghossian, Arshak and Sch{\"o}ning, Michael Josef},
  title     = {Facile Purification and Use of Tobamoviral Nanocarriers for Antibody-Mediated Display of a Two-Enzyme System},
  series = {Viruses},
  volume    = {9},
  journal   = {Viruses},
  number    = {15},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {1999-4915},
  doi       = {doi.org/10.3390/v15091951},
  pages     = {Artikel 1951},
  year      = {2023},
  abstract  = {Immunosorbent turnip vein clearing virus (TVCV) particles displaying the IgG-binding domains D and E of Staphylococcus aureus protein A (PA) on every coat protein (CP) subunit (TVCVPA) were purified from plants via optimized and new protocols. The latter used polyethylene glycol (PEG) raw precipitates, from which virions were selectively re-solubilized in reverse PEG concentration gradients. This procedure improved the integrity of both TVCVPA and the wild-type subgroup 3 tobamovirus. TVCVPA could be loaded with more than 500 IgGs per virion, which mediated the immunocapture of fluorescent dyes, GFP, and active enzymes. Bi-enzyme ensembles of cooperating glucose oxidase and horseradish peroxidase were tethered together on the TVCVPA carriers via a single antibody type, with one enzyme conjugated chemically to its Fc region, and the other one bound as a target, yielding synthetic multi-enzyme complexes. In microtiter plates, the TVCVPA-displayed sugar-sensing system possessed a considerably increased reusability upon repeated testing, compared to the IgG-bound enzyme pair in the absence of the virus. A high coverage of the viral adapters was also achieved on Ta2O5 sensor chip surfaces coated with a polyelectrolyte interlayer, as a prerequisite for durable TVCVPA-assisted electrochemical biosensing via modularly IgG-assembled sensor enzymes.},
  language  = {en}
}
@article{WernerGroebelKrumbeetal.2012,
  author    = {Werner, Frederik and Groebel, Simone and Krumbe, Christoph and Wagner, Torsten and Selmer, Thorsten and Yoshinobu, Tatsuo and Baumann, Marcus and Sch{\"o}ning, Michael Josef},
  title     = {Nutrient concentration-sensitive microorganism-based biosensor},
  series = {Physica Status Solidi (a)},
  volume    = {209},
  journal   = {Physica Status Solidi (a)},
  number    = {5},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1862-6319},
  doi       = {10.1002/pssa.201100801},
  pages     = {900 -- 904},
  year      = {2012},
  language  = {en}
}
@article{WernerGroebelSchuhmacheretal.2009,
  author    = {Werner, Frederik and Groebel, Simone and Schuhmacher, K. and Spelthahn, Heiko and Wagner, Torsten and Selmer, Thorsten and Baumann, Marcus and Sch{\"o}ning, Michael Josef},
  title     = {Bestimmung der metabolischen Aktivit{\"a}t von Mikroorganismen w{\"a}hrend des Biogasbildungsprozesses},
  series = {9. Dresdner Sensor-Symposium : Dresden, 07.-09. Dezember 2009 / Gerlach, Gerald ; Hauptmann, Peter [Hrsg.]},
  journal   = {9. Dresdner Sensor-Symposium : Dresden, 07.-09. Dezember 2009 / Gerlach, Gerald ; Hauptmann, Peter [Hrsg.]},
  publisher = {TUDpress},
  address   = {Dresden},
  isbn      = {978-3-941298-44-6},
  pages     = {201 -- 204},
  year      = {2009},
  language  = {de}
}
@article{WernerGroebelWagneretal.2011,
  author    = {Werner, Frederik and Groebel, Simone and Wagner, Torsten and Yoshinobu, Tatsuo and Selmer, Thorsten and Baumann, Marcus and Sch{\"o}ning, Michael Josef},
  title     = {{\"U}berwachung der metabolischen Aktivit{\"a}t von Mikroorganismen zur Kontrolle des biologischen Prozesses im Biogasfermenter},
  series = {Biogas 2011 : Energietr{\"a}ger der Zukunft ; 6. Fachtagung, Fachtagung Braunschweig, 08. und 09. Juni 2011 / VDI Energie und Umwelt},
  journal   = {Biogas 2011 : Energietr{\"a}ger der Zukunft ; 6. Fachtagung, Fachtagung Braunschweig, 08. und 09. Juni 2011 / VDI Energie und Umwelt},
  publisher = {VDI-Verl.},
  address   = {D{\"u}sseldorf},
  isbn      = {978-3-18-092121-1},
  pages     = {285 -- 286},
  year      = {2011},
  language  = {de}
}
@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}
}
@inproceedings{WernerMansourRateikeetal.2011,
  author    = {Werner, Frederik and Mansour, Ahmed and Rateike, Franz-Matthias and Schusser, Sebastian and Wagner, Torsten and Yoshinobu, Tatsuo and Keusgen, Michael and Sch{\"o}ning, Michael Josef},
  title     = {Kompakter Aufbau eines lichtadressierbaren potentiometrischen Sensors mit verfahrbarem Diodenlaser},
  series = {10. Dresdner Sensor-Symposium : Dresden, 5. - 7. Dezember 2011 ; miniaturisierte analytische Verfahren, Hochtemperatur-Sensoren, Sensoren f{\"u}r Bioprozess- und Verfahrenstechnik, Sensoren f{\"u}r die Medizin, Chemische Verfahrenstechnik, Lebensmittelanalytik, innovative Sensorl{\"o}sungen, Sensoren f{\"u}r die Wasserqualit{\"a}t, Selbst{\"u}berwachung / Gerald Gerlach ... (Hg.) Dresdner Beitr{\"a}ge zur Sensorik. 43},
  booktitle = {10. Dresdner Sensor-Symposium : Dresden, 5. - 7. Dezember 2011 ; miniaturisierte analytische Verfahren, Hochtemperatur-Sensoren, Sensoren f{\"u}r Bioprozess- und Verfahrenstechnik, Sensoren f{\"u}r die Medizin, Chemische Verfahrenstechnik, Lebensmittelanalytik, innovative Sensorl{\"o}sungen, Sensoren f{\"u}r die Wasserqualit{\"a}t, Selbst{\"u}berwachung / Gerald Gerlach ... (Hg.) Dresdner Beitr{\"a}ge zur Sensorik. 43},
  editor    = {Gerlach, Gerald},
  publisher = {TUDpress},
  address   = {Dresden},
  isbn      = {978-3-942710-53-4},
  pages     = {277 -- 280},
  year      = {2011},
  language  = {de}
}
@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{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{WernerSpelthahnSchoeningetal.2010,
  author    = {Werner, Frederik and Spelthahn, H. and Sch{\"o}ning, Michael Josef and Krumbe, C. and Wagner, Torsten and Yoshinobu, T. and Keusgen, M.},
  title     = {Neue Ansteuerungselektronik f{\"u}r LAPS-basierte Biosensoren zur gleichzeitig ortsaufgel{\"o}sten Messung der pH-Konzentration},
  series = {Sensoren und Messsysteme 2010 [Elektronische Ressource] : Vortr{\"a}ge der 15. ITG/GMA-Fachtagung vom 18. bis 19. Mai 2010 in N{\"u}rnberg / Informationstechnische Gesellschaft im VDE (ITG); VDI/VDE-Gesellschaft Mess- und Automatisierungstechnik (GMA)},
  journal   = {Sensoren und Messsysteme 2010 [Elektronische Ressource] : Vortr{\"a}ge der 15. ITG/GMA-Fachtagung vom 18. bis 19. Mai 2010 in N{\"u}rnberg / Informationstechnische Gesellschaft im VDE (ITG); VDI/VDE-Gesellschaft Mess- und Automatisierungstechnik (GMA)},
  publisher = {VDE Verlag},
  address   = {Berlin},
  isbn      = {978-3-8007-3260-9},
  pages     = {109 -- 114},
  year      = {2010},
  language  = {de}
}
@article{WernerTakenagaTakietal.2013,
  author    = {Werner, Frederik and Takenaga, Shoko and Taki, Hidenori and Sawada, Kazuaki and Sch{\"o}ning, Michael Josef},
  title     = {Comparison of label-free ACh-imaging sensors based on CCD and LAPS},
  series = {Sensors and Actuators B: Chemical (2012)},
  volume    = {177},
  journal   = {Sensors and Actuators B: Chemical (2012)},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {0925-4005},
  pages     = {745 -- 752},
  year      = {2013},
  abstract  = {Semiconductor-based chemical imaging sensors, like the light-addressable potentiometric sensor (LAPS) or the pH-imaging sensor based on a charge-coupled device (CCD), are becoming a powerful tool for label-free imaging of biological phenomena. We have proposed a polyion-based enzymatic membrane to develop an acetylcholine (ACh) imaging sensor for neural cell-activity observations. In this study, a CCD-type ACh-imaging sensor and a LAPS-type ACh-imaging sensor were fabricated and the prospect of both sensors was clarified by making a comparison of their basic characteristics.},
  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{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}
}
@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{WertIkenSchoeningetal.2021,
  author    = {Wert, Stefan and Iken, Heiko and Sch{\"o}ning, Michael Josef and Matysik, Frank-Michael},
  title     = {Development of a temperature-pulse enhanced electrochemical glucose biosensor and characterization of its stability via scanning electrochemical microscopy},
  series = {Electroanalysis},
  journal   = {Electroanalysis},
  number    = {Early View},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1521-4109},
  doi       = {10.1002/elan.202100089},
  year      = {2021},
  abstract  = {Glucose oxidase (GOx) is an enzyme frequently used in glucose biosensors. As increased temperatures can enhance the performance of electrochemical sensors, we investigated the impact of temperature pulses on GOx that was drop-coated on flattened Pt microwires. The wires were heated by an alternating current. The sensitivity towards glucose and the temperature stability of GOx was investigated by amperometry. An up to 22-fold increase of sensitivity was observed. Spatially resolved enzyme activity changes were investigated via scanning electrochemical microscopy. The application of short (<100 ms) heat pulses was associated with less thermal inactivation of the immobilized GOx than long-term heating.},
  language  = {en}
}
@inproceedings{WuBronderPoghossianetal.2014,
  author    = {Wu, Chunsheng and Bronder, Thomas and Poghossian, Arshak and Sch{\"o}ning, Michael Josef},
  title     = {DNA-hybridization detection using light-addressable potentiometric sensor modified with gold layer},
  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{WuBronderPoghossianetal.2014,
  author    = {Wu, Chunsheng and Bronder, Thomas and Poghossian, Arshak and Werner, Frederik and B{\"a}cker, Matthias and Sch{\"o}ning, Michael Josef},
  title     = {Label-free electrical detection of DNA with a multi-spot LAPS: First step towards light-addressable DNA chips},
  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.201330442},
  pages     = {1423 -- 1428},
  year      = {2014},
  abstract  = {A multi-spot (4 × 4 spots) light-addressable potentiometric sensor (MLAPS) consisting of an Al-p-Si-SiO2 structure has been applied for the label-free electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization by the intrinsic molecular charge for the first time. Single-stranded probe ssDNA molecules (20 bases) were covalently immobilized onto the silanized SiO2 gate surface. The unspecific adsorption of mismatch ssDNA on the MLAPS gate surface was blocked by bovine serum albumin molecules. To reduce the screening effect and to achieve a high sensor signal, the measurements were performed in a low ionic-strength solution. The photocurrent-voltage (I-V) curves were simultaneously recorded on all 16 spots after each surface functionalization step. Large shifts of I-V curves of 25 mV were registered after the DNA immobilization and hybridization event. In contrast, a small potential shift (∼5 mV) was observed in case of mismatch ssDNA, revealing good specificity of the sensor. The obtained results demonstrate the potential of the MLAPS as promising transducer platform for the multi-spot label-free electrical detection of DNA molecules by their intrinsic molecular charge.},
  language  = {en}
}
@article{WuBronderPoghossianetal.2015,
  author    = {Wu, Chunsheng and Bronder, Thomas and Poghossian, Arshak and Werner, Frederik and Sch{\"o}ning, Michael Josef},
  title     = {Label-free detection of DNA using light-addressable potentiometric sensor modified with a positively charged polyelectrolyte layer},
  series = {Nanoscale},
  volume    = {14},
  journal   = {Nanoscale},
  number    = {7},
  publisher = {Royal Society of Chemistry (RSC)},
  address   = {Cambridge},
  doi       = {10.1039/C4NR07225A},
  pages     = {6143 -- 6150},
  year      = {2015},
  abstract  = {A multi-spot (16 spots) light-addressable potentiometric sensor (MLAPS) consisting of an Al-p-Si-SiO2 structure modified with a weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)) was applied for the label-free electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization by the intrinsic molecular charge for the first time. To achieve a preferentially flat orientation of DNA strands and thus, to reduce the distance between the DNA charge and MLAPS surface, the negatively charged probe single-stranded DNAs (ssDNA) were electrostatically adsorbed onto the positively charged PAH layer using a simple layer-by-layer (LbL) technique. In this way, more DNA charge can be positioned within the Debye length, yielding a higher sensor signal. The surface potential changes in each spot induced due to the surface modification steps (PAH adsorption, probe ssDNA immobilization, hybridization with complementary target DNA (cDNA), non-specific adsorption of mismatched ssDNA) were determined from the shifts of photocurrent-voltage curves along the voltage axis. A high sensor signal of 83 mV was registered after immobilization of probe ssDNA onto the PAH layer. The hybridization signal increases from 5 mV to 32 mV with increasing the concentration of cDNA from 0.1 nM to 5 μM. In contrast, a small signal of 5 mV was recorded in the case of non-specific adsorption of fully mismatched ssDNA (5 μM). The obtained results demonstrate the potential of the MLAPS in combination with the simple and rapid LbL immobilization technique as a promising platform for the future development of multi-spot light-addressable label-free DNA chips with direct electrical readout.},
  language  = {en}
}