Thiazolyl blue tetrazolium bromide

3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide; MTT; Methylthiazolyldiphenyl-tetrazolium bromide

MTT is a tetrazolium dye that is used to measure cell viability and metabolic activity in vitro. It is also used as a marker for assessing the cytotoxicity of anticancer drugs, antibiotics, and chemotherapeutic agents. MTT has been shown to induce autophagy in tumor cells, which may be due to its ability to decrease mitochondrial membrane potential and activate voltage-dependent calcium channels. MTT is toxic when injected into living animals and humans; therefore, it should be handled with care. The LD50 of intravenous administration in rats has been determined to be 1 g/kg body weight (mg/kg).