Category
Chemical Primary Standard
CAS Number
531-55-5
Molecular Formula
C15H16ClN3S
Molecular Weight
305.83 g/mol
Synonym

Phenothiazin-5-ium, 3-(dimethylamino)-7-(methylamino)-, chloride;Azure B chloride

Keywords
Miscellaneous compounds
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Methylene blue (chemical name: 3-(Dimethylamino)-7-(methylamino)phenothiazin-5-ium chloride) is a synthetic phenothiazine dye. It appears as a deep blue crystalline solid and is widely used as a biological stain and redox indicator. In medicine, it is used to treat methemoglobinemia and as a diagnostic dye.