STAINING, PRACTICAL AND THEORETICAL 



to 100*^ C. Filter the solution while it is still hot, and again after 

 it has been allowed to cool. 



2. Cut frozen sections, from formalin fixed material, and wash 

 them in water for about five minutes to remove excess formalin. 



3. Dehydrate the sections by agitating them gently with a camel 

 hair brush for three minutes in each of two changes of pure 

 anhydrous ethylene glycol. 



4. Transfer the sections to the staining solution for five to 

 seven minutes, agitating them gently at intervals. 



5. Differentiate by agitating the sections gently in 85% ethylene 

 glycol in water for two to five minutes, controlling by examining 

 under the microscope at intervals. 



6. Transfer to a large dish of distilled water for three to five 

 minutes. 



7. Float sections onto slides; drain and carefully blot away 

 excess water. 



8. Mount in glycerine jelly, Farrant or Aquamount. 



Note: Either ethylene or propylene glycol may be used; how- 

 ever, the former usually costs less than the latter. 



Reference: Chiflfelle, T. L. & Putt, F. A. (1951). 



PROPYL ALCOHOL, NORMAL (OR ISO) 

 For dehydrating and clearing tissues prior to embedding 



Technique: 



1 . Pieces of fixed tissue are placed directly into normal propyl 

 alcohol and left therein overnight. 



2. Transfer directly into a bath of paraffin wax M.P. 40° C. 



3. After infiltration of the 40° C. wax, transfer to a bath of 

 52-54° C. paraffin wax for a few minutes; then cast the block. 



Note: This method prevents hardening and distortion of tissue : 

 it is particularly recommended for scirrhous carcinoma, connec- 

 tive tissue, tumours, etc. 



5M 



