@article{WincklerKruegerSchnitzleretal.2014,
  author    = {Winckler, Silvia and Krueger, Rolf and Schnitzler, Thomas and Zang, Werner and Fischer, Rainer and Biselli, Manfred},
  title     = {A sensitive monitoring system for mammalian cell cultivation processes: a PAT approach},
  series = {Bioprocess and biosystems engineering},
  volume    = {37},
  journal   = {Bioprocess and biosystems engineering},
  number    = {5},
  publisher = {Springer},
  address   = {Berlin, Heidelberg},
  issn      = {1615-7591 (Print) 1615-7605 (Online)},
  doi       = {10.1007/s00449-013-1062-8},
  pages     = {901 -- 912},
  year      = {2014},
  abstract  = {Biopharmaceuticals such as antibodies are produced in cultivated mammalian cells, which must be monitored to comply with good manufacturing practice. We, therefore, developed a fully automated system comprising a specific exhaust gas analyzer, inline analytics and a corresponding algorithm to precisely determine the oxygen uptake rate, carbon dioxide evolution rate, carbon dioxide transfer rate, transfer quotient and respiratory quotient without interrupting the ongoing cultivation, in order to assess its reproducibility. The system was verified using chemical simulation experiments and was able to measure the respiratory activity of hybridoma cells and DG44 cells (derived from Chinese hamster ovary cells) with satisfactory results at a minimum viable cell density of ~2.0 × 10⁵ cells ml⁻¹. The system was suitable for both batch and fed-batch cultivations in bubble-aerated and membrane-aerated reactors, with and without the control of pH and dissolved oxygen.},
  language  = {en}
}
@article{MeyerStorkHoeckerBerndt1992,
  author    = {Meyer-Stork, L. Sebastian and H{\"o}cker, Hartwig and Berndt, Heinz},
  title     = {Syntheses and reactions of urethanes of cellobiose and cellulose-containing uretdione groups},
  series = {Journal of applied polymer science},
  volume    = {44},
  journal   = {Journal of applied polymer science},
  number    = {6},
  issn      = {1097-4628},
  pages     = {1043 -- 1049},
  year      = {1992},
  language  = {en}
}
@article{HemmerlingMerschenzQuackWunderlich1988,
  author    = {Hemmerling, H.-J. and Merschenz-Quack, Angelika and Wunderlich, H.},
  title     = {Crystal structures of indeno[1,2-d]imidazoles. XIth European Crystallographic Meeting, Vienna 1988},
  series = {Zeitschrift f{\"u}r Kristallographie - Crystalline Materials},
  volume    = {185},
  journal   = {Zeitschrift f{\"u}r Kristallographie - Crystalline Materials},
  number    = {H. 1-4},
  issn      = {2196-7105 (E-Books); 2194-4946 (Print)},
  pages     = {256},
  year      = {1988},
  language  = {en}
}
@article{AbulnagaPinkenburgSchiffelsetal.2013,
  author    = {Abulnaga, El-Hussiny and Pinkenburg, Olaf and Schiffels, Johannes and E-Refai, Ahmed and Buckel, Wolfgang and Selmer, Thorsten},
  title     = {Effect of an Oxygen-Tolerant Bifurcating Butyryl Coenzyme A Dehydrogenase/Electron-Transferring Flavoprotein Complex from Clostridium difficile on Butyrate Production in Escherichia coli},
  series = {Journal of bacteriology},
  volume    = {195},
  journal   = {Journal of bacteriology},
  number    = {16},
  issn      = {1098-5530 [E-Journal]},
  pages     = {3704 -- 3713},
  year      = {2013},
  language  = {en}
}
@article{SchiffelsPinkenburgScheldenetal.2013,
  author    = {Schiffels, Johannes and Pinkenburg, Olaf and Schelden, Maximilian and Aboulnaga, El-Hussiny A. A. and Baumann, Marcus and Selmer, Thorsten},
  title     = {An innovative cloning platform enables large-scale production and maturation of an oxygen-tolerant [NiFe]-hydrogenase from cupriavidus necator in Escherichia coli},
  series = {PLOS one. 2013},
  journal   = {PLOS one. 2013},
  publisher = {Public Library of Science},
  address   = {San Francisco, California},
  issn      = {1932-6203},
  doi       = {10.1371/journal.pone.0068812},
  year      = {2013},
  language  = {en}
}
@article{HuckSchiffelsHerreraetal.2013,
  author    = {Huck, Christina and Schiffels, Johannes and Herrera, Cony N. and Schelden, Maximilian and Selmer, Thorsten and Poghossian, Arshak and Baumann, Marcus and Wagner, Patrick and Sch{\"o}ning, Michael Josef},
  title     = {Metabolic responses of Escherichia coli upon glucose pulses captured by a capacitive field-effect sensor},
  series = {Physica Status Solidi (A)},
  volume    = {210},
  journal   = {Physica Status Solidi (A)},
  number    = {5},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {0031-8965},
  doi       = {10.1002/pssa.201200900},
  pages     = {926 -- 931},
  year      = {2013},
  abstract  = {Living cells are complex biological systems transforming metabolites taken up from the surrounding medium. Monitoring the responses of such cells to certain substrate concentrations is a challenging task and offers possibilities to gain insight into the vitality of a community influenced by the growth environment. Cell-based sensors represent a promising platform for monitoring the metabolic activity and thus, the "welfare" of relevant organisms. In the present study, metabolic responses of the model bacterium Escherichia coli in suspension, layered onto a capacitive field-effect structure, were examined to pulses of glucose in the concentration range between 0.05 and 2 mM. It was found that acidification of the surrounding medium takes place immediately after glucose addition and follows Michaelis-Menten kinetic behavior as a function of the glucose concentration. In future, the presented setup can, therefore, be used to study substrate specificities on the enzymatic level and may as well be used to perform investigations of more complex metabolic responses. Conclusions and perspectives highlighting this system are discussed.},
  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{BaeckerRaueSchusseretal.2012,
  author    = {B{\"a}cker, Matthias and Raue, Markus and Schusser, Sebastian and Jeitner, C. and Breuer, L. and Wagner, P. and Poghossian, Arshak and F{\"o}rster, Arnold and Mang, Thomas and Sch{\"o}ning, Michael Josef},
  title     = {Microfluidic chip with integrated microvalves based on temperature- and pH-responsive hydrogel thin films},
  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.201100763},
  pages     = {839 -- 845},
  year      = {2012},
  abstract  = {Two types of microvalves based on temperature-responsive poly(N-isopropylacrylamide) (PNIPAAm) and pH-responsive poly(sodium acrylate) (PSA) hydrogel films have been developed and tested. The PNIPAAm and PSA hydrogel films were prepared by means of in situ photopolymerization directly inside the fluidic channel of a microfluidic chip fabricated by combining Si and SU-8 technologies. The swelling/shrinking properties and height changes of the PNIPAAm and PSA films inside the fluidic channel were studied at temperatures of deionized water from 14 to 36 °C and different pH values (pH 3-12) of Titrisol buffer, respectively. Additionally, in separate experiments, the lower critical solution temperature (LCST) of the PNIPAAm hydrogel was investigated by means of a differential scanning calorimetry (DSC) and a surface plasmon resonance (SPR) method. Mass-flow measurements have shown the feasibility of the prepared hydrogel films to work as an on-chip integrated temperature- or pH-responsive microvalve capable to switch the flow channel on/off.},
  language  = {en}
}
@article{BaeckerRakowskiPoghossianetal.2013,
  author    = {B{\"a}cker, Matthias and Rakowski, D. and Poghossian, Arshak and Biselli, Manfred and Wagner, Patrick and Sch{\"o}ning, Michael Josef},
  title     = {Chip-based amperometric enzyme sensor system for monitoring of bioprocesses by flow-injection analysis},
  series = {Journal of Biotechnology},
  volume    = {163},
  journal   = {Journal of Biotechnology},
  number    = {4},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0168-1656},
  doi       = {10.1016/j.jbiotec.2012.03.014},
  pages     = {371 -- 376},
  year      = {2013},
  abstract  = {A microfluidic chip integrating amperometric enzyme sensors for the detection of glucose, glutamate and glutamine in cell-culture fermentation processes has been developed. The enzymes glucose oxidase, glutamate oxidase and glutaminase were immobilized by means of cross-linking with glutaraldehyde on platinum thin-film electrodes integrated within a microfluidic channel. The biosensor chip was coupled to a flow-injection analysis system for electrochemical characterization of the sensors. The sensors have been characterized in terms of sensitivity, linear working range and detection limit. The sensitivity evaluated from the respective peak areas was 1.47, 3.68 and 0.28 μAs/mM for the glucose, glutamate and glutamine sensor, respectively. The calibration curves were linear up to a concentration of 20 mM glucose and glutamine and up to 10 mM for glutamate. The lower detection limit amounted to be 0.05 mM for the glucose and glutamate sensor, respectively, and 0.1 mM for the glutamine sensor. Experiments in cell-culture medium have demonstrated a good correlation between the glutamate, glutamine and glucose concentrations measured with the chip-based biosensors in a differential-mode and the commercially available instrumentation. The obtained results demonstrate the feasibility of the realized microfluidic biosensor chip for monitoring of bioprocesses.},
  language  = {en}
}
@article{SpiessWilfriedAlvarezetal.2011,
  author    = {Spiess, Elmar and Wilfried, Reichardt and Alvarez, Gerardo and Gottrup, Marcus and {\"O}hlschl{\"a}ger, Peter},
  title     = {An Artificial PAP Gene Breaks Self-tolerance and Promotes Tumor Regression in the TRAMP Model for Prostate Carcinoma},
  series = {Molecular Therapy},
  volume    = {20},
  journal   = {Molecular Therapy},
  number    = {3},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {1525-0016},
  pages     = {555 -- 564},
  year      = {2011},
  language  = {en}
}