78 Biological Stains 



c41 BORDEAUX RED C. I. NO. 88 



Synonyms: Fast red B, BN or P. Cerasin R. Archelline 2B. 

 Azo- Bordeaux. Acid Bordeaux. 



Various grades denoted: Bordeaux By BL, G, Ry R exira. 



NaSOj SOjNa 



C2oHi2N207S2Na2; Mol. Wt. 502.426 



{An acid dye; absorption maximum about 520) 



Solubility at 26° C: in water 3.88%; in alcohol 0.19% 



Bordeaux red is used as a cytoplasmic stain, as, for example, in 

 aqueous solution when Heidenhain's hematoxylin is to be used 

 immediately afterward as a nuclear stain. It has also been used 

 with thionin and methyl green for staining sections, particularly 

 of spleen, testis, and liver. Lillie (1940) finds it a fairly satis- 

 factory substitute for xylidine ponceau in the Masson technic. 



c45 SUDAN R C. I. NO. II3 



Synonyms : Brilliant fat scarlet B. Oil vermillion. 



OCH3 OH 



C17H14N2O2; Md. Wt. 278.298 



{A weakly acid dye; absorption maxima 569 \519.8]) 



Weichherz (1934) has recently used a Sudan R III (possibly this 

 dye or possibly Sudan III) in connection with the Kahn reaction 

 for the diagnosis of syphilis. It makes the reading of the tubes 

 easier. 



c50 JANUS GREEN B C. I. NO. 133 



Synonyms: Diazin green S. Union green B. 



This is an azo dye having an azin as well as an azo chromophore 

 group, and is thus related to the safranins. It is a compound of 

 diethyl safranin with dimethyl anihn through an azo group. 



