Cresol Red

Chemical properties

Dark green or brown-red powder

The Uses of Cresol Red

Cresol red is commonly used with lead acetate for the detection of urease after PAGE. It is also used as an indicator with the following transition intervals: pH 1.8 (orange) to pH 2.0 (yellow); pH 7.0 (yellow) to pH 8.8 (violet). Cresol Red is used as a tracking dye in DNA, RNA (agarose) and protein (polyacrylamide) electrophoresis. In agarose, Cresol Red runs with an apparent molecular size of approx. 125 bp DNA. Cresol Red does not inhibit Taq polymerase.

The Uses of Cresol Red

Acid-base indicator.

What are the applications of Application

Cresol red is a stain commonly used with lead acetate for detection of urease after PAGE

Definition

ChEBI: A member of the class of 2,1-benzoxathioles that is 2,1-benzoxathiole 1,1-dioxide in which both of the hydrogens at position 3 have been substituted by 4-hydroxy-5-methylphenyl groups.

Purification Methods

Crystallise it from glacial acetic acid. Dry it in air. Dissolve it in aqueous 5% NaHCO3 solution and precipitate it from a hot solution by dropwise addition of aqueous HCl. Repeat the procedure till the UVmax does not increase. [Beilstein 19 IV 1133.]