Cytotoxicity is the quality of being toxic to cells. Cells exposed to a cytotoxic compound can respond in a number of ways. The cells may undergo necrosis, in which they lose membrane integrity and die rapidly as a result of cell lysis; they can stop growing and dividing; or they can activate a genetic program of controlled cell death, termed apoptosis.
There are many ways to measure cytotoxicity, but most involve assessment of cell membrane integrity. Membrane integrity can be evaluated by using vital dyes (such as trypan blue or propidium iodide), by protease biomarkers, with MTT or MTS redox potential assays, or by measuring ATP content. Many of these assays involve colorimetric, fluorescence, or luminescence detection.
With one of the widest ranges of detection technologies on the market today, Molecular Devices can provide the bioanalytical and analytical products that you need to conduct cytotoxicity measurements, from cytometry and high-content screening systems to multi-mode microplate analysis systems to high-throughput cellular screening systems.
Cytotoxicity assays are widely used by the pharmaceutical industry to screen for cytotoxicity in compound libraries. Researchers can either look for cytotoxic compounds, if they are interested in developing a therapeutic that targets rapidly dividing cancer cells, for instance; or they can screen "hits" from initial high-throughput drug screens for unwanted cytotoxic effects before investing in their development as a pharmaceutical.
