CA Index Name: 1H-Indole-5-sulfonic acid, 2-(1,3-dihydro-3-oxo-5-sulfo-2H-indol-2-ylidene)-2,3-dihydro-3-oxo-, sodium salt
Other Names: 1H-Indole-5-sulfonic acid, 2-(1,3-dihy-dro-3-oxo-5-sulfo-2H-indol-2-ylidene)-2,3-dihydro-3-oxo-, disodium salt; C.I. Acid Blue 74; [A2,2'-Biindoline]-5,50-disulfonic acid, 3,30-dioxo-, disodium salt; 12070 Blue; 1311 Blue; 5,5'-Indigodisulfonic acid disodium salt; A.F. Blue No. 2; Acid Blue 74; Acid Blue W; Acid Leather Blue IC; Airedale Blue IN; Amacid Brilliant Blue; Aniline Carmine Powder; Ariavit Indigo Carmine; Atul Indigo Carmine; Basovit Blue 665E; Blue 2; Bucacid Indigotine B; C.I. 73015; C.I. 75781; C.I. Food Blue 1; C.I. Natural Blue 2; Canacert Indigo Carmine; Carmine Blue; Cilefa Blue R; Cogilor Blue 511.11; Disodium 5,5'-indigodisul-fonate; Disodium 5,5'-indigotin disulfonate; Dolkwal Indigo Carmine; E 132; Edicol Supra Blue X; Eurocert Indigo Carmine 311811; FD & C Blue 2; FD & C Blue No. 2-307045; FD and C Blue 2; FD and C Blue No. 2; FD&C Blue No. 2; FD&C Blue No. 2-37006; Food Blue 1; Food Blue 2; Food Blue No. 1; Food Blue No. 2; Grape Blue A; HD Indigo Carmine; HD Indigo Carmine Supra; Hexacert Blue No. 2; Hexacol Indigo Carmine Supra; Indigo Carmine 307019; Indigo Carmine 36009; Indigo Carmine 37006; Indigo Carmine A; Indigo Carmine AC; Indigo Carmine BP; Indigo Carmine Conc. FQ; Indigo Carmine Powder; Indigo Carmine X; Indigo Extract; Indigo carmine; Indigo carmine NB; Indigotin; Indigotin (solubilized); Indigotine; Indigotine B; Indigotine Blue LZ; Indigotine Carmine; Indigotine Extra Pure A; Indigotine I; Indigotine IA; Indigotine Lake; Indigotine N; Indigotine disodium salt; Indocarmine F; Intense Blue; Japan Blue 2; Japan Food Blue No. 2; L Blue 5010; Maple Indigo Carmine; Mitsui Indigo Carmine; Necol Indigo Carmine; Neelicol Indigo Carmine; Sanei Indigo Carmine; Sepisperse Dry 1003; Sodium 5,5'-indigodisulfo-nate; Sodium 5,50-indigotindisulfonate; Soluble indigo; Soluble indigo blue; Sumitomo Wool Blue SBC; Usacert Blue No. 2; Usacert FD & C Blue No. 2-310118; Usacert FD and C Blue No. 2; WAS 35; Water Blue 177557; Water Blue 177558
Merck Index Number: 4944
Chemical / Dye Class: Indole
Molecular Formula: C16H8N2Na2O8S2
Molecular Weight: 466.35
Physical Form: Dark blue-purple powder, sensitive to light
Solubility: Soluble in water; slightly soluble in ethanol
Melting Point: > 250 °C
pH Range: 11.5-14.0
Color Change at pH: Blue (11.5) to yellow (14.0)
Absorption (λmax): 608 nm
Synthesis: Synthetic methods
Staining Applications: Cells; beverages; chewing gum; candies; drinks; frozen products; sweetener; tablets; dosage form; sunscreen; skin; hairs
Biological Applications: Detecting microorganisms; treating amyloidosis, testicular cancer; medical devices; drug delivery system
Industrial Applications: Color filters; display devices; inks; toners; lithographic printing plates; paints; photographic material; colored bubbles; toys
Safety / Toxicity: Acute toxicity; carcinogenicity; chromosome aberrations; chronic toxicity; cytotoxicity; genotoxicity; hypertension; hypotension; mutagenicity; nucleic acid damage
Certification / Approval: Certified by Biological Stain Commission (BSC); Approved by Food & Drugs Administration (FDA)