ALIZARIN RED S 



Synonyms: Alizarin red, water soluble. 



Alizarin sulphate. 



c. I. NO. 1034 

 Alizarin carmin. 



SOjNa 



{An acid dye.) 



This dye, sodium alizarin sulphonate, is used by Benda for stain- 

 ing chromatin in combination with crystal violet, the chromatin 

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

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

 by Schrotter for sections of nervous tissue. 



PURPURIN c. I. NO. 1037 



Synonyms: Alizarin No. 6. Alizarinpurpurin. 



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



[Jf.o5.o\ 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. 



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