68 Biological Stains 



Bio MARTIUS YELLOW C. I. NO. 9 



Synonyms: Manchester yellow. Naphthol yellow. 



This dye is usually the sodium, or sometimes calcium or am- 

 monium, salt of the following acid: 



OH 



I 

 . NO2 



NO2 

 C10H6N2O5; Mol. Wt. 234.164 



{An acid dye; absorption maxima about IflfB^ [399, 379] ) 



Solubility of sodium salt at 26° C: in water 1^.57%; in alcohol 

 0.16%. Solubility of calcium salt: in water 0.05%; in al- 

 cohol 1.90%) 



Martins yellow has been used by Pianese (1896) in combination 

 with malachite green and acid fuchsin for studying cancer tissue; 

 the same technic was applied to plant tissue by Muller (1912), and 

 is now quite extensively used by plant pathologists in studying 

 sections of tissue infected by fungi. More recently it has been 

 employed by Nebel (1931) in contrast to resorcin blue for staining 

 pollen tubes in styles. Halbert (1935), by adding it to bacteriolog- 

 ical media, finds that it favors the growth of Escherichia coliy 

 but inhibits Aerobacter aerogenes. The dye is also used in prepar- 

 ing certain light filters used in photomicrography. 



This dye is not at present available in America. 



For technic of Pianese III B Stain, see Staining Procedures, p. IIA-12. 



For technic of Lacmoid-martlus-yellow stain for pollen tubes, see Id. p. IIA-14. 



Bl5 AURANTIA C. I. NO. 12. 



Synonym: Imperial yellow. 



This dye is the ammonium salt of hexanitro-diphenylamine. 



NO. NOa O— NH, 



O.N_/— \_N=/~\=N=0 



V_/ \_/ 



/ / 



NO. NO, 



C12H8N8O12; Mol. Wt. 456.248 



{An acid dye; absorption maximum about 4^25) 



Solubility at 26°C: in water nil; in alcohol O.S3%o 



