D6.4 - Chemical Sensors for Bio-Scientific Research – From in Vitro to in Vivo

SENSOR+TEST Conferences 2011
2011-06-07 - 2011-06-09
Proceedings SENSOR 2011
D6 - Medical I
J. Kieninger, K. Aravindalochanan, B. Enderle, G. Urban, H. Flamm, A. Weltin - Albert-Ludwigs-Universität Freiburg -IMTEK- (Germany)
634 - 637


Chemical sensors provide important information about metabolic processes in both, in vitro (in cell culture) and in vivo (in living organisms) measurements. Parameters of interest are oxygen, pH, glucose and lactate. Depending on the objective of the experiments, nitric oxide, reactive oxygen species (superoxide) and glutamate can also be important parameter to be measured.
The talk will provide an overview about the similarities and differences between electrochemical sensor systems for in vitro and in vivo applications. Different types of cell culturing (adherent cells, suspension cultures) are discussed for in vitro. The locations and their implication for measurements in vivo, such as brain or muscle tissue, are illustrated.
For both, the in vitro and in vivo situation a system was developed and will be presented: The Sensing Cell Culture Flask (SCCF) is a technical platform for in vitro research comprising a conventional tissue culture flask with integrated sensor chips. Equipped with different electrochemical sensors, the system can be used for long-time monitoring during cell culture experiments as well as to study short-time responses of cells to external stimuli.
The most important parameter in vitro is the oxygen concentration. Due to cellular respiration the oxygen tension close to the cells (pericellular) can significantly deviate from what is preset in the incubator atmosphere. This occurs because of concentration gradients along the cell culture medium. With the SCCF system equipped with oxygen sensors it was shown, that cells in normoxic condition (19.9% oxygen in incubator atmosphere) can reach pericellular levels as low as it would be expected in hypoxic incubation condition (4% oxygen). Those experiments illustrate the necessity of pericellular oxygen monitoring especially in the field hypoxia (tumour) research.
For multiparameter monitoring in vivo a flexible sensor strip was developed. Results from measurements with oxygen and biosensors in neurological research as well as in muscle tissue demonstrate the challenges during those animal experiments.
It can be concluded that the demands for the individual electrochemical sensor points are nearly comparable in vitro and in vivo, while aspects of system integration differs significantly.