Neutral Red (or toluylene red, Basic Red 5, or C.I. 50040) is a eurhodin dye used for staining in histology. It stains lysosomes red. It is used as a general stain in histology, as a counterstain in combination with other dyes, and for many staining methods. Together with Janus Green B, it is used to stain embryonal tissues and supravital staining of blood. Can be used for staining Golgi apparatus in cells and Nissl granules in neurons.
Neutral red can be used as a vital stain, to stain living cells. It is used to stain cell cultures for plate titration of viruses.
Neutral Red is added to some growth media for bacteria and cell cultures. It usually comes as a chloride salt.
Neutral Red acts as a pH indicator, changing from red to yellow between the pH 6.8-8.0.
Famous quotes containing the words neutral and/or red:
“I feel the carousel starting slowly
And going faster and faster: desk, papers, books,
Photographs of friends, the window and the trees
Merging in one neutral band that surrounds
Me on all sides, everywhere I look.”
—John Ashbery (b. 1927)
“What blazed ahead of you? A faked road block?
The red lamp swung, the sudden brakes and stalling
Engine, voices, heads hooded and the cold-nosed gun?”
—Seamus Heaney (b. 1939)