Janus Green B

green powder

Janus Green B is a stain that interacts with DNA and has been used for histology studies including mitochondrial staining, in which its oxidation and reduction reveals alterations to the electron transfer chain. The stain has been utilized in studies for effective and rapid staining of insect chordotonal organs and peripheral nerves, where the nerves appear dark blue in comparison to non stained tissue. With the use of Janus Green B, rabbit lymphatic vessel studies demonstrate that threadlike structures within the lymphatic vessels, known as Bonghan ducts, contain a high density of mitochondria in their cells.

As dye for cotton, wool; as biological stain; in electrodeposition of copper, Brown, Fellows, US 2882209 (1959 to Udylite Res. Corp.).

ChEBI: Janus Green B chloride is an organic chloride salt. It has a role as a dye. It contains a Janus Green B cation.

Janus Green B belongs to the phenazine group of dyes. It is a dark green/dark brown/dark black powder. Janus Green B should be oxidized to become colored. Thus, this dye can be used to specifically stain mitochondria in living cells. It has been used to stain biomolecules, nucleic acids and chromosomes. In addition, it is also used to stain various living organisms including fungi, yeast cell, brain, spinal cord, sperms and tissue culture monolayer. Janus Green B acts as an antimalarial agent. It also facilitates diagnostic assays and diagnosis of disease related to amyloid accumulation.

Poison by intraperitoneal and intravenous routes. Moderately toxic by ingestion, skin contact, subcutaneous, and intramuscular routes. Human systemic effects by inhalation: nausea or vomiting. A skin and severe eye irritant. Flammable liquid when exposed to heat or flame; can react with oxidizing materials. To fight fire, use alcohol foam, CO2, dry chemical. When heated to decomposition it emits toxic fumes of NOx. See also AMINES.

The dye dissolves in H2O to give a bluish violet solution which becomes colourless when made 10M in NaOH. It dissolves in EtOH to give a blue-violet colour, filter from insoluble material, then add dry Et2O whereby the dye separates out leaving a small amount of blue colour in solution. Filter off the solid and dry it in a vacuum. Store it in a dark bottle. [Colour Index Vol 4, 3rd edn, 4015 1971.]