MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



Technique: 



1. Any fixative may be employed, but if Bouin is chosen, remove 

 picric acid with a few drops of saturated lithium carbonate in the 

 70% alcohol of dehydration series. Should a fixative containing 

 mercuric chloride be chosen, then it will, of course, be necessary 

 to remove mercuric precipitate in the usual way. 



2. After fixation, wash, dehydrate, clear and embed in paraffin 

 wax. 



3. Cut sections no thicker than 7-5// and fix to slides, avoiding 

 the use of glycerine albumin, which will cloud the stain. 



4. De-wax with xylol ; then pass through absolute, 90% and 

 70% alcohol to water. 



5. Stain in the safranin solution for twenty-four hours. 



6. Rinse with water. 



7. Stain with the crystal violet for one to two minutes. 



8. Wash with water. 



9. Immerse in 50% alcohol for two minutes. 



10. Immerse in 95% alcohol for two minutes. 



11. Immerse in the fast green-orange 2 (Solution C) for five 

 minutes. 



12. Differentiate, examining under the microscope, until the 

 connective tissue is stained to the desired depth of green. 



13. Immerse in clove oil for ten minutes. 



14. Transfer to Orange 2 in clove oil for ten minutes. 



15. Differentiate, examining under the microscope at intervals, 

 until the desired depth of staining has been achieved. 



16. Immerse for ten minutes each in two changes of xylol. 



17. Mount in balsam. 



Results: 



Nuclei, red. Nucleoli, purple or purpHsh red. Nuclear mem- 

 brane, dark red. Cellular cytoplasm, pink to red, except in Henle's 

 loop (light green). Connective tissue, green. Elastic fibres, yellow. 

 Fibroblasts, green with purple nuclei. Muscle, reddish brown. 

 Erythrocytes, orange. Polymorphonuclears show purple nuclei. 



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