Bone Marrow Staining 227 



Brooke and Donaldson (1930) recommend the use of Triton X-30, 

 a nonionic liquid detergent to prevent the transfer of malarial para- 

 sites between films when mass staining. 



Bone Marrow Staining 



Maximow's Eosin- Azure Stain (block et al., 1953) 



fixation: Zenker-neutral formalin: 2 hours. Neutralize formalin by 

 adding 2 gm. lithium or magnesium carbonate to 500 ml. of formalin. 

 Excess of carbonate should be present. Wash in rimning water 1-24 

 hours before preparation for embedding. (See Comment 4) 



solutions: 

 Solution A: 



eosin Y, C.I. 45380 0.1 gm. 



distilled water 100.0 ml. 



Solution B: 



azure II 0.1 gm. 



distilled water 100.0 ml. 



Working solution: 



distilled water 85.0 ml. 



Solution A 15.0 ml. 



Stirring vigorously, add gradually 



Solution B 10.0 ml. 



Fresh solutions are best; their action deteriorates after 3 or 4 weeks. 

 Working solution should appear deep violet in color, and a precipi- 

 tate should not form in it for an hour or more. If a precipitate forms 

 on the slides, the stain mixture was improperly made; solution B was 

 added to solution A too rapidly or without stirring. If the eosin loses 

 its brilliance, solutions are old. 



procedure: 



1. Deparaffinize and hydrate slides to water; remove HgCU. If tissue 

 was fixed in a fixative without potassium dichromate, chromate 

 .slides overnight in 2.5-3% aqueous potassium dichromate. Wash 

 thoroughly in running water: 15 minutes. Proceed to step 2. 



2. Stain in Mayer's hematoxylin: 30-45 seconds, no more. (See Com- 

 ment 3.) 



