STAINING, PRACTICAL AND THEORETICAL 



Technique: 



1. Tissues should be fixed in i% aqueous picric acid or in 

 absolute alcohol, and Celloidin sections should be employed. 



2. Stain for ten minutes in the safranin solution; then wash 

 thoroughly in water. 



3. Stain for ten to fifteen minutes in Solution B. 



4. Wash thoroughly in distilled water. 



5. Clear in Bergamot oil: then mount in Clearmount. 



Results: 



Collagen fibres are stained blue, while nuclei are red. 



SCARLET R - ETHYLENE GLYCOL 



An improved technique for staining fat, etc. in animal tissues, 

 its chief advantages being: [a) Excellent differentiation without 

 loss of stain out of the lipid particles, {b) A stable solution which 

 does not dissolve lipid materials, (c) Sections are not shrunken 

 but remain pliable, {d) More intense staining of fat. 



Solutions required: 



A. Ethylene glycol, pure, anhydrous. 



B. Scarlet R . . . . . . . . i gm. 



Ethylene Glycol, pure, anhydrous. . 100 ml. 



Heat the ethylene glycol to 100-110° C. on 

 a hot plate or in an oven, or over the bunsen 

 flame, taking care that it does not catch fire; 

 then add the stain and stir until all or most of 

 it is dissolved. Filter when cold. 



C. Ethylene glycol, pure, anhydrous. . 85 ml. 

 Distilled water . . . . . . 15 ml. 



D. Ehrlich or Delafield haematoxylin. 



Technique: 



1. Fix material in 10% formalin and cut frozen sections. 



2. Wash sections in water for two minutes or longer to remove 

 the formalin. 



3. Dehydrate the sections by agitating gently in pure anhydrous 

 ethylene glycol for three to five minutes. 



398 



