Miscellaneous Dyes 227 



This dye, sodium alizarin sulfonate, was used by Ben,da for stain- 

 ing chromatin in combination with crystal violet, the chromatin 

 staining brown, while the mitochondria stain violet. It has also 

 been used as a vital stain for nervous tissue in small invertebrates, 

 and by Schrotter (See Lee, p. 465) for sections of nerve tissue. A 

 recent application is for the gross staining of skeletons (Dawson, 

 1926, Lipman, 1935, Hollister, 1934); in fact, its most frequent 

 modern use is as a stain for bone. Backman (1935) employs it as 

 a chromosome stain in plant cytology. 



For various methods calling for this dye in staining bone, see Staining Procedures, 

 pp. ID3-I2-I7. 



ElO PURPURIN C. I. NO. 1037 



Synonyms: Alizarin N0.6. Alizarin purpurin. 



r 



O OH 



/ OH 



II OH 



O 



CuHsOs; Mol. Wt. 256.204 



{An acid dye; absorption maxima about [521.1], Jf85.5, 



[It35.5] in alcohol.) 



Purpurin is very similar to alizarin, but forms scarlet red lakes 

 with alumina. It has been used as a nuclear stain for histological 

 material, and for determining the presence of insoluble calcium 

 salts in the cell contents. 



Ell QUINALIZARIN C. I. NO. IO45 



Synonym: Alizarin Bordeaux BA. 



HO O OH 



II / 



OH 



y 



HO 

 CuHgOe; Mol Wt. 272.204 

 {An add dye) 



