Scarlet, Biebrich

Commercial Biebrich scarlet is generally this disulphonic acid, sometimes it contains the monosulphonic acid also. Both give a green solution with concentrated sulphuric acid. The shade obtained on wool and silk is a beautiful cochineal scarlet. 

Azo dyes which contain two chromophore groups, NrrN, and which are called dis- or tetr-azo dyes, can be prepared two methods may be employed (i) The starting-point is an amido-azo-compound which already contains one azo group this is diazotised, and then united with an amine or phenol- Biebrich scarlet is obtained in this way. by diazotising the disulphonic add of amidoazobenzene, and combining it with /3-naphthol ... 

The amidoazobenzene hydrochloride came into the market formerly, as a yellow dye, under tire name of Aniline Yellow. At present, it is scarcely used, but there is prepared from it, by heating with sulphuric acid, a mono- or di-sulphonic acid, which in the form of its alkali salts finds application as a dye under the name of Acid Yellow, or Fast Yellow. As already mentioned under the dis-azo dyes, from the diazo-compound of this dye, Biebrich Scarlet may be made-by combination with /3-naphthol. Finally, the amidoazobenzene is still used for the preparation of the Induline dyes. 

Biebrich Scarlet [4196-99-0] Cl 26905 Xmax 505 nm, I(2)986B, U137, SH413A, SR(2)2763D b... 

Organism grows in media containing 0.01% Biebrich scarlet. 

Allcock also used different types of poly[(organo)phosphazenes] based on ethyl and benzyl esters of amino acids as side groups (Allcock et al., 1994). Small molecules like ethacrynic acid, a diuretic, and Biebrich Scarlet, an azo dye, w ere incorporated as model release components. 

Acid dyestuffs Congo Red, Trypan Red, Nigrosine, Biebrich Scarlet, Eosine, Alizarine Red. 

Biebrich scarlet was discovered in 1878/9, a very pure red disazo dye said originally to rival cochineal in brightness . It is described by Zerr and Riibencamp (1906). Synonyms include Ponceau Biebrich Scarlet, Cl 26905/Acid Red 66, Croceine Scarlet and Double Scarlet BSF. Now principally used as a histological stain. 

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