The kit supplies reagents for P.A.S. (Periodic Acid Schiff) staining. Schiff reagent is an aqueous-based, colorless solution used in combination with periodic acid to highlight aldehyde group. P.A.S. staining is mainly used to visualize the presence of glycogen but also glyco-proteins. Many tissues may result P.A.S positive, for example: the ground substance of connective tissues, cartilage, bones, mucous cells and glands, kidney structures, hypophysis basophil cells, thyroid colloid substance.