MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



Technique: 



1. Sections are placed on slides and flooded with the phloro- 

 glucinol solution which is allowed to act for about five minutes. 



2. Pour off excess phloroglucinol and cover sections with a few 

 drops of concentrated hydrochloric acid, cover with a coverslip 

 and examine under the microscope. 



Result: 



Lignified tissues are stained red. 



POLYVINYL LACTOPHENOL 



For embedding brittle specimens of wood for sectioning. 



It is claimed that this technique has given successful results 



with wood dating back to the Roman era 



In addition to softening the wood for cutting, this technique also 

 clears the specimen and allows cell walls, which may have been 

 blackened through carbonization, to become clear and translucent, 

 thereby facilitating identification under the microscope. 



Solution required: 

 Polyvinyl Lactophenol. 

 Technique: 



1. Immerse blocks of wood cubed in the usual manner, in 

 polyvinyl alcohol, and warm gently for thirty minutes. 



2. Drain, and allow to cool for twenty-four hours. 



3. Cut sections from blocks with a very sharp razor. 



Results: 



The wood has lost its brittleness and has acquired a soft pliable 

 rubber-like nature. 



Reference: Levy, J. F. L. (1953), Nature, 171, 984. 



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