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 lonely Earth amid the balls
That hurry through the eternal halls,
A makeweight flying to the void,
Supplemental asteroid,
Or compensatory spark,
Shoots across the neutral Dark.”
—Ralph Waldo Emerson (1803–1882)
“...I didn’t consider intellectuals intelligent, I never liked them or their thoughts about life. I defined them as people who care nothing for argument, who are interested only in information; or as people who have a preference for learning things rather than experiencing them. They have opinions but no point of view.... Their talk is the gloomiest type of human discourse I know.... This is a red flag to my nature. Intellectuals, to me have no natures ...”
—Margaret Anderson (1886–1973)