STAINING, PRACTICAL AND THEORETICAL 



(c) It is claimed that this method (the OTAN method) rests 

 upon a physico-chemical difference between classes of lipids, and 

 for this reason the method may be regarded as histochemical, or 

 histophysical. 



(d) The original paper should be consulted for more detailed 

 information and tables. 



References : 



Adams, C. W. M. (1959). 



Carleton, H. M. and Leach, E. H. (1947), p. 126. 



PAPANICOLAOU STAIN EA36 

 For improved difFerentiation of the cells of vaginal smears 



Staining solutions: 



A. Ehrlich or Harris haematoxylin. 



B. Papanicolaou stain OG6 



Orange G . . . . . . 0-2 gm. 



Alcohol 95% 100 ml. 



Phosphotungstic acid . . . . 0-015 g^- 



C. Papanicolaou stain, EA36, recipe as solution page 341. 



Place in a flask, plug the neck lightly with 

 cotton- wool; then heat, on a waterbath until 

 dissolved. Cool, then filter. 



Technique: 



1 . Wet smears are fixed in a mixture of equal volumes of ether 

 and absolute alcohol for five to fifteen minutes. 



2. Rinse successively in 90%, 70% and 50% alcohols and dis- 

 tilled water. 



3. Stain in Ehrlich's haematoxylin for five to ten minutes. 



4. Rinse in distilled water; differentiate in 0-5% hydrochloric 

 acid. 



5. Rinse in distilled water; then leave for one minute in dilute 

 lithium carbonate solution (three drops saturated lithium carbon- 

 ate to 100 ml. distilled water). 



6. Rinse thoroughly in distilled water and wash successively in 

 50%. 70%. 95% alcohol. 



340 



