@article{DantismTakenagaWagneretal.2017,
  author    = {Dantism, Shahriar and Takenaga, Shoko and Wagner, Torsten and Wagner, Patrick and Sch{\"o}ning, Michael Josef},
  title     = {Differential imaging of the metabolism of bacteria and eukaryotic cells based on light-addressable potentiometric sensors},
  series = {Electrochimica Acta},
  volume    = {246},
  journal   = {Electrochimica Acta},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0013-4686},
  doi       = {10.1016/j.electacta.2017.05.196},
  pages     = {234 -- 241},
  year      = {2017},
  abstract  = {A light-addressable potentiometric sensor (LAPS) is a field-effect-based potentiometric sensor with an electrolyte/insulator/semiconductor (EIS) structure, which is able to monitor analyte concentrations of (bio-)chemical species in aqueous solutions in a spatially resolved way. Therefore, it is also an appropriate tool to record 2D-chemical images of concentration variations on the sensor surface. In the present work, two differential, LAPS-based measurement principles are introduced to determine the metabolic activity of Escherichia coli (E. coli) K12 and Chinese hamster ovary (CHO) cells as test microorganisms. Hereby, we focus on i) the determination of the extracellular acidification rate (ΔpH/min) after adding glucose solutions to the cell suspensions; and ii) recording the amplitude increase of the photocurrent (Iph) related to the produced acids from E. coli K12 bacteria and CHO cells on the sensor surface by 2D-chemical imaging. For this purpose, 3D-printed multi-chamber structures were developed and mounted on the planar sensor-chip surface to define four independent compartments, enabling differential measurements with varying cell concentrations. The differential concept allows eliminating unwanted drift effects and, with the four-chamber structures, measurements on the different cell concentrations were performed simultaneously, thus reducing also the overall measuring time.},
  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}
}
@article{ErmolenkoVlasovKolodnikovetal.2004,
  author    = {Ermolenko, Y.E. and Vlasov, Y.G. and Kolodnikov, V.V. and Shabaldkin, D. A. and Kloock, Joachim P. and Sch{\"o}ning, Michael Josef},
  title     = {Diffusion of radioactive tracers (204Tl, 110mAg) and ionic conductivity in membrane materials for the chemical sensors},
  series = {Advances in nuclear and radiochemistry : extended abstracts of papers presented at the Sixth International Conference on Nuclear and Radiochemistry (NRC-6), 29 August to 3 September 2004, Aachen, Germany ; in cooperation with University of Cologne, GDCh, FECS, OECD-NEA and IAEA / Syed M. Qaim ... (eds.).},
  journal   = {Advances in nuclear and radiochemistry : extended abstracts of papers presented at the Sixth International Conference on Nuclear and Radiochemistry (NRC-6), 29 August to 3 September 2004, Aachen, Germany ; in cooperation with University of Cologne, GDCh, FECS, OECD-NEA and IAEA / Syed M. Qaim ... (eds.).},
  publisher = {Forschungszentrum J{\"u}lich, Zentralbibliothek},
  address   = {J{\"u}lich},
  isbn      = {3893363629},
  pages     = {483 -- 485},
  year      = {2004},
  language  = {en}
}
@article{KeusgenKloockKnobbeetal.2004,
  author    = {Keusgen, M. and Kloock, Joachim P. and Knobbe, D.-T. and J{\"u}nger, M. and Krest, I. and Goldbach, M. and Klein, W. and Sch{\"o}ning, Michael Josef},
  title     = {Direct determination of cyanides by potentiometric biosensors},
  series = {Sensors and Actuators B. 103 (2004), H. 1-2},
  journal   = {Sensors and Actuators B. 103 (2004), H. 1-2},
  isbn      = {0925-4005},
  pages     = {380 -- 385},
  year      = {2004},
  language  = {en}
}
@article{SchoeningKloockKnobbeetal.2004,
  author    = {Sch{\"o}ning, Michael Josef and Kloock, Joachim P. and Knobbe, D.-T. and Krause, R. and Block, K. and Wang, J. and Mulchandani, A. and Keusgen, M.},
  title     = {Direktnachweis von Pestiziden und Cyanid mit elektrochemischen Enzymsensoren},
  series = {Sensoren und Messsysteme 2004 : Tagung Ludwigsburg, 15. und 16. M{\"a}rz 2004 / VDI-VDE-Gesellschaft Mess- und Automatisierungstechnik},
  journal   = {Sensoren und Messsysteme 2004 : Tagung Ludwigsburg, 15. und 16. M{\"a}rz 2004 / VDI-VDE-Gesellschaft Mess- und Automatisierungstechnik},
  publisher = {VDI},
  address   = {D{\"u}sseldorf},
  isbn      = {3-18-091829-2},
  pages     = {699 -- 706},
  year      = {2004},
  language  = {en}
}
@article{BongaertsEsserLorbachetal.2011,
  author    = {Bongaerts, Johannes and Esser, Simon and Lorbach, Volker and Al-Momani, L{\´o}ay and M{\"u}ller, Michael A. and Franke, Dirk and Grondal, Christoph and Kurutsch, Anja and Bujnicki, Robert and Takors, Ralf and Raeven, Leon and Wubbolts, Marcel and Bovenberg, Roel and Nieger, Martin and Sch{\"u}rmann, Melanie and Trachtmann, Natalie and Kozak, Stefan and Sprenger, Georg A. and M{\"u}ller, Michael},
  title     = {Diversity-oriented production of metabolites derived from chorismate and their use in organic synthesis},
  series = {Angewandte Chemie International Edition},
  volume    = {Vol. 50},
  journal   = {Angewandte Chemie International Edition},
  number    = {Iss. 34},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1521-3773 (E-Journal); 0570-0833 (Print); 1433-7851 (Print)},
  pages     = {7781 -- 7786},
  year      = {2011},
  language  = {en}
}
@article{GamellaZakharchenkoGuzetal.2017,
  author    = {Gamella, Maria and Zakharchenko, Andrey and Guz, Nataliia and Masi, Madeline and Minko, Sergiy and Kolpashchikov, Dmitry M. and Iken, Heiko and Poghossian, Arshak and Sch{\"o}ning, Michael Josef and Katz, Evgeny},
  title     = {DNA computing system activated by electrochemically triggered DNA realease from a polymer-brush-modified electrode array},
  series = {Electroanalysis},
  volume    = {29},
  journal   = {Electroanalysis},
  number    = {2},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1521-4109},
  doi       = {10.1002/elan.201600389},
  pages     = {398 -- 408},
  year      = {2017},
  abstract  = {An array of four independently wired indium tin oxide (ITO) electrodes was used for electrochemically stimulated DNA release and activation of DNA-based Identity, AND and XOR logic gates. Single-stranded DNA molecules were loaded on the mixed poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA)/poly(methacrylic acid) (PMAA) brush covalently attached to the ITO electrodes. The DNA deposition was performed at pH 5.0 when the polymer brush is positively charged due to protonation of tertiary amino groups in PDMAEMA, thus resulting in electrostatic attraction of the negatively charged DNA. By applying electrolysis at -1.0 V(vs. Ag/AgCl reference) electrochemical oxygen reduction resulted in the consumption of hydrogen ions and local pH increase near the electrode surface. The process resulted in recharging the polymer brush to the negative state due to dissociation of carboxylic groups of PMAA, thus repulsing the negatively charged DNA and releasing it from the electrode surface. The DNA release was performed in various combinations from different electrodes in the array assembly. The released DNA operated as input signals for activation of the Boolean logic gates. The developed system represents a step forward in DNA computing, combining for the first time DNA chemical processes with electronic input signals.},
  language  = {en}
}
@article{BronderPoghossianSchejaetal.2015,
  author    = {Bronder, Thomas and Poghossian, Arshak and Scheja, Sabrina and Wu, Chunsheng and Keusgen, Michael and Mewes, Dieter and Sch{\"o}ning, Michael Josef},
  title     = {DNA Immobilization and Hybridization Detection by the Intrinsic Molecular Charge Using Capacitive Field-Effect Sensors Modified with a Charged Weak Polyelectrolyte Layer},
  series = {Applied Materials \& Interfaces},
  volume    = {36},
  journal   = {Applied Materials \& Interfaces},
  number    = {7},
  publisher = {American Chemical Society},
  address   = {Washington, DC},
  doi       = {10.1021/acsami.5b05146},
  pages     = {20068 -- 20075},
  year      = {2015},
  abstract  = {Miniaturized setup, compatibility with advanced micro- and nanotechnologies, and ability to detect biomolecules by their intrinsic molecular charge favor the semiconductor field-effect platform as one of the most attractive approaches for the development of label-free DNA chips. In this work, a capacitive field-effect EIS (electrolyte-insulator-semiconductor) sensor covered with a layer-by-layer prepared, positively charged weak polyelectrolyte layer of PAH (poly(allylamine hydrochloride)) was used for the label-free electrical detection of DNA (deoxyribonucleic acid) immobilization and hybridization. The negatively charged probe single-stranded DNA (ssDNA) molecules were electrostatically adsorbed onto the positively charged PAH layer, resulting in a preferentially flat orientation of the ssDNA molecules within the Debye length, thus yielding a reduced charge-screening effect and a higher sensor signal. Each sensor-surface modification step (PAH adsorption, probe ssDNA immobilization, hybridization with complementary target DNA (cDNA), reducing an unspecific adsorption by a blocking agent, incubation with noncomplementary DNA (ncDNA) solution) was monitored by means of capacitance-voltage and constant-capacitance measurements. In addition, the surface morphology of the PAH layer was studied by atomic force microscopy and contact-angle measurements. High hybridization signals of 34 and 43 mV were recorded in low-ionic strength solutions of 10 and 1 mM, respectively. In contrast, a small signal of 4 mV was recorded in the case of unspecific adsorption of fully mismatched ncDNA. The density of probe ssDNA and dsDNA molecules as well as the hybridization efficiency was estimated using the experimentally measured DNA immobilization and hybridization signals and a simplified double-layer capacitor model. The results of field-effect experiments were supported by fluorescence measurements, verifying the DNA-immobilization and hybridization event.},
  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{SchoeningWangKrauseetal.2002,
  author    = {Sch{\"o}ning, Michael Josef and Wang, Josepf and Krause, Robin and Block, Kirstin and Musameh, Mustafa and Mulchandani, Ashok and Mulchandani, Priti and Chen, Wilfred},
  title     = {Dual amperometric-potentiometric biosensor detection system for monitoring organophosphorus neurotoxins},
  series = {Analyica Chimica Acta. 469 (2002), H. 2},
  journal   = {Analyica Chimica Acta. 469 (2002), H. 2},
  isbn      = {0378-4304},
  pages     = {197 -- 203},
  year      = {2002},
  language  = {en}
}