Hematoxylin is extracted from logwood (Haematoxylon campechianum L.). Hematoxylin oxidates to hematein and binds with metal ions (mordants). Hematein turns into insoluble nuclear color. Positively charged hematein-mordant complex then binds with negatively charged phosphate ions of the DNA’s nucleus, creating characteristic blue coloration. There are various hematoxylin solutions, such as histological staining reagents (Hematoxylin H, Hematoxylin M, Hematoxylin ML, Hematoxylin G1, Hematoxylin G2, Hematoxylin G3, Hematoxylin PTA, Hematoxylin W kit) and cytology reagents (Hematoxylin G1, Hematoxylin G2, Hematoxylin G3, Hematoxylin HP). Although each of the listed reagents has a specific use, each provides excellent results of staining nuclear membrane, nucleoplasm and nucleolus.