Name of the dye

Methylene Blue

Reactive Blue-250

Formula

C₁₆H₁₈ClN₃S

C₂₇H₂₃N₅Na₄O₂₀S₆

Molecular weight

319.85 g/mol

1021.9 g/mol

Chemical structure

Structural category

Thiazine dye

Azo dye

Dye type

Cationic

Anionic