[Chips instead of mice: cells on bioelectronic sensor-chips as an alternative to animal experiments]

An alternative assay for replacing animal experiments should serve the specific microphysiological needs of the cells and be endowed with multiparametric signal monitoring. These requirements are provided by a test system in which the key elements are biocompatible electronic sensor-chips. It is also connected to a medium perfusion set-up, which allows to control the supply of nutrients and test compounds, and the removal of culture medium. The chips are equipped with sensors that continuously monitor basic metabolic parameters and membrane-associated changes of living cells: pH-ISFETs for extracellular acidification, amperometric O2-sensors for oxygen consumption, and IDES for electrical impedance of the cell layer. Experiments with LS174T colon carcinoma cells in culture show the metabolic and electrical changes upon incubation with Zytochalasin B and chloroacetaldehyde. The signal patterns vary and indicate different mechanisms of action for these test compounds. With this test system it is possible to detect effects of unknown substances and mixtures, and to analyse the cellular probe for prolonged times.