A technique to tocopherol (vitamin E) histochemical detection

A technique to detect tocopherol histochemically was proposed in basis on the following schedule: 1. toluidine blue and Schiff reagent negativity before a suitable oxidation; 2. performic acid-toluidine blue and performic acid-Schiff reagent positivity after fixing in formalin-CaCl2; 3. performic acid-toluidine blue and performic acid-Schiff reagent negativity after fixing in formalin-HgCl2; 4. ferric ferricyanide reaction positivity not influenced by the formalin-HgCl2 blockade. This technique tested on filter paper strips loaded with several lipids, steroids, vitamins, proteins, amino acids and ribonucleic acid shows that it is specific to tocopherols among the tested substances. Used on tissue sections this technique appears as very suitable to histochemical purposes.