Tissue Morphology and Cell Impedance Based Biosensors for Toxicity Testing

In vitro neurotoxicity testing and toxicity effect quantification plays an important role in many disciplines of biomedicine as an alternative to in vivo methods. The principle of the majority of in vitro methods corresponds to the basic concept of biosensors, i.e. measured quantity is by means of biological sensing element transformed to physical quantity easily measurable by electrical methods of measurement. Two types of biosensors suitable for neurotoxicity measurements are described in the paper. A common feature for both types is application of a living organism as biological sensing element. In the first type of biosensor the morphology of cell is evaluated using image processing methods known as videometry. In the second type of biosensors the electrical impedance of cells using an improved version of the ECIS (Electric Cell-substrate Impedance Sensing) method is a measure of toxicity effects. The results of experiments with biosensors using videometry and a proposal for improvements of ECIS based biosensors are included in the paper.