Quinone-iTnine Dyes 119 



KlO GALLOCYANIN C. I. NO. 883 



Synonyms: Alizarin blue RBN. Chrom blue GCB. Fast violet. 



COOH 



I 

 CH3 /\_N_ 



/ 

 CH3 



N~X/~0=\/"~0 

 OH 



C15H12N2O5; Mol. Wt. 300.262 

 {Absorption maximum about 636) 



Proescher and Arkush (1928) found the iron lake of this dye» 

 prepared by boiling 2-3 minutes in a 5% aqueous solution of ferric 

 ammonium sulfate, to be a splendid nuclear stain to be employed 

 as a substitute for hematoxylin. Buzaglo (1934) used it, in com- 

 bination with orcein and an acid alizarin blue, as a tissue stain. 

 It has also found employment (Foley, 1943) as a counterstain in 

 one of the protargol staining methods for nervous tissue. 



For technic of Foley's combined method for staining nerve fibers, see Staining 

 Procedures, p. ICj-SS. 



K15 GALLAMIN BLUE C. I. NO. 894 



CONH2 



CH3 /\_N_/\ 



\ I J II 



N~\/~0=\/"~OH 



/ I I 



CH3 CI OH 



C15H14N3O4CI; Mol. Wt. 335.743 



(Absorption maximum about 651) 



Employed in the form of its iron lake by Proescher and Arkush 

 (1928) as a nuclear stain; the lake is prepared as described for 

 gallocyanin above. It has been recommended by Stock (1949) 

 for detecting calcium in tissues. 



The following very similar dye has also been mentioned in 

 biological literature, chiefly for its value as an oxidation-reduc- 

 tion indicator: 



Prune pure; C. I. No. 893. Syn.: Violet PDH. Gallo blue E. 

 Very similar to gallamin blue, but a methyl ester instead of an 

 amide. 



