Mitochondria in cheek cell stained by Janus green B in laboratory

A basic azo and cationic dye Janus green B is used to stain mitochondria. This technique was introduced by scientist Michaelis L in 1900. In the presence of oxygen dye Janus green B oxidizes and gives blue colour. Where as in the absence of oxygen dye reduces and changes to pink colour.
We can also use Mitoview dye ( fluorogenic) for mitochondria staining for live cells. This dye accumulates in mitochondria so we can imaged it.