Janus Green B is a basic dye and vital stain used in histology. It is also used to stain mitochondria supravitally, as was introduced by Leonor Michaelis in 1900.Michaelis, L. (1900). Die vitale Farbung, eine Darstellungsmethode der Zellgranula. Archiv für mikroskopische Anatomie 55:558-575(Also Tafel XXXII)
The indicator Janus Green B changes colour according to the amount of oxygen present. When oxygen is present, the indicator oxidizes to a blue colour. In the absence of oxygen, the indicator is reduced and changes to a pink colour.
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