Fluorescent Probes as Tools in In Vitro Toxicology

A number of different endpoints reflecting cell viability are commonly used to assess cytotoxicity. These endpoints are then taken to reflect cell death. It is not possible to elucidate the basis of the toxic mechanisms involved in these tests. However, by using a number of different endpoints to monitor different cellular events, the information that can be obtained from in vitro toxicity tests could be increased. Fluorescent probes appear to be promising alternatives for assessing cytotoxicity, and such probes are available for a number of different cellular events. In addition to viability, more-specific cellular events can be monitored, including intracellular glutathione levels, mitochondrial membrane potentials and intracellular concentrations of various ions. The possibility of using several fluorescent probes simultaneously, and hence of making measurements of several different cellular events at the same time, further increases the usefulness of fluorescent probes.