A dual staining method for neutral complex carbohydrates using alkaline phosphatase-labeled concanavalin a and periodic acid-Schiff

Summary A method has been developed for the dual staining of neutral complex carbohydrates in light microscopy. It combines an alkaline phosphatase-labeled concanavalin A-5-bromo-3-indolyl phosphate, p-toluidine salt (Con A-ALP-BIPT) method with periodic acid-Schiff (PAS) sequence. With the present dual staining method, it is possible to color -d-glucosyl and -d-mannosyl residues blue and 1,2-glycol groups of neutral complex carbohydrates magenta. The validity of this method has been confirmed with appropriate histochemical controls and enzyme digestions on test tissues.