Abstract
Oxidation with chromyl chloride in an anhydrous solvent followed by exposure to Schiff's reagent can be used for the demonstration of glycogen and mucins in tissue sections. The intensity of the reaction is weaker than in the periodic acid-Schiff technique and other substances besides glycogen and mucins generally fail to react. Acetylation and deacetylation abolish and restore the reaction respectively.
On prolonged exposure to chromyl chloride at room temperature a typical Feulgen nucleal reaction is obtained. Treatment with the following inorganic acid chlorides in carbon tetrachloride also results in Feulgen staining: sulfuryl chloride thionyl chloride and phosphoryl chloride. Current views concerning the mechanism of aldehyde group liberation in the Feulgen reaction are discussed in connection with these results.