In-vitro cell models are used for disease modelling, for screening active substances and for toxicity tests, as well as for fundamental research into the development and organization of diverse types of tissue. Based on our expertise in the fields of cell biology, material sciences and coatings, as well as microsensor systems and microfluidics (design, production and integration), we develop microreactors for short-term and long-term studies on cell aggregates. These reactors allow cells to be cultured under controlled physiological conditions. The integration of microsensors into these systems allows, for the very first time, the continual measurement of cell vitality or metabolites for up to one month in real time. In comparison to conventional endpoint analyses, this approach provides far more immediate access to an understanding of the mechanisms of action. Along with concept creation and the development of micro-bioreactors, we also conduct in-vitro analyses to assess the hepatotoxicity of chemical substances.