Azure B is effective for staining of chromosomes. It's a cationic dye, and component of the Romanowsky stain. Also, it is utilized for the localization of nucleic acids and staining of blood films. It is secure for the use and meets the industrial standard. The best and suitable dye is Azure B. Its alternative names are: Azure I, Methylene Azure, and Trimethylthionine chloride. The dye is used for staining semi-thin segments of the plant tissues, and for distinguishing DNA (blue-green) and cellular RNA (purplish). It is helpful in the methods such as NCCLS for blood smears and Nocht's for paraffin sections. We keep up with needful composition, chemical & physical properties, and safe packaging. One should prepare & use the solution on the same day.