Cytotoksisitest

Cytotoxicity testing is a fundamental assay in toxicology and drug discovery used to evaluate the potential of a substance to cause cell death. This type of test determines if a compound or material exhibits harmful effects on living cells. The principle behind cytotoxicity testing is to expose cells in a controlled environment to varying concentrations of the test substance and then measure the resulting cell viability or death. Several methods exist to quantify cytotoxicity. Common techniques include assays that measure metabolic activity, such as the MTT or WST assays, which rely on the conversion of a substrate by living, metabolically active cells into a colored product. Another approach involves assessing membrane integrity; for instance, the trypan blue exclusion assay identifies cells with compromised cell membranes, indicating they are non-viable. Cell proliferation assays can also be employed to indirectly measure cytotoxicity by observing the rate at which cells grow. The results are typically expressed as an IC50 value (half-maximal inhibitory concentration), which represents the concentration of the substance required to inhibit cell viability by 50%. Cytotoxicity testing is crucial for assessing the safety of pharmaceuticals, chemicals, and medical devices before they are used in humans or released into the environment. It helps in identifying potentially toxic compounds early in the development process, thereby reducing the risk of adverse effects.