Micro-dosing device and micro-sensors for pH control in parallel bioreactors

Nils Janzen, doctoral thesis Technische Universität München, 2014

At first a micro-dosing device equipped with 144 magnetic-inductive micro membrane pumps was optimized and characterized to enable fed-batch processes in parallel stirred-tank bioreactors. This was demonstrated with high cell density cultivations of recombinant Escherichia coli on a 10 mL scale. Secondly, new fluorimetric pH-sensors for pH monitoring of parallel bioprocesses at low pH (pH < 6.0) were characterized and applied in parallel fermentations with Clostridium acetobutylicum as an application example.


  • Janzen N, Schmidt M, Krause C, Weuster-Botz D (2015): Evaluation of fluorimetric pH-sensors for bioprocess monitoring at low pH. Bioproc Biosys Eng 38: 1685-1692.
  • Faust G, Janzen N, Bendig C, Römer L, Kaufmann K, Weuster-Botz D (2014): Feeding strategies enhance high cell density cultivation and protein expression in milliliter-scale bioreactors. Biotechnol J 9: 1293-1303.