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:
“The United States must be neutral in fact as well as in name.... We must be impartial in thought as well as in action ... a nation that neither sits in judgment upon others nor is disturbed in her own counsels and which keeps herself fit and free to do what is honest and disinterested and truly serviceable for the peace of the world.”
—Woodrow Wilson (1856–1924)
“With the old kindness, the old distinguished grace,
She lies, her lovely piteous head amid dull red hair
Propped upon pillows, rouge on the pallor of her face.
She would not have us sad because she is lying there,
And when she meets our gaze her eyes are laughter-lit,
Her speech a wicked tale that we may vie with her....”
—William Butler Yeats (1865–1939)