Neutral Red

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 seashore is a sort of neutral ground, a most advantageous point from which to contemplate this world. It is even a trivial place. The waves forever rolling to the land are too far-traveled and untamable to be familiar. Creeping along the endless beach amid the sun-squall and the foam, it occurs to us that we, too, are the product of sea-slime.”
    —Henry David Thoreau (1817–1862)

    “I was here first introduced to Joe.... He was a good-looking Indian, twenty-four years old, apparently of unmixed blood, short and stout, with a broad face and reddish complexion, and eyes, methinks, narrower and more turned up at the outer corners than ours, answering to the description of his race. Besides his underclothing, he wore a red flannel shirt, woolen pants, and a black Kossuth hat, the ordinary dress of the lumberman, and, to a considerable extent, of the Penobscot Indian.”
    —Henry David Thoreau (1817–1862)