Indigo carmine

analytical standard

Indigo-5,5′-disulfonic acid disodium salt, Indigocarmine, Acid Blue 74
Empirical Formula (Hill Notation):
CAS Number:
Molecular Weight:
Colour Index Number:
Beilstein/REAXYS Number:
EC Number:
MDL number:
PubChem Substance ID:
E Number:


analytical standard

Quality Level


≥97.0% (HPLC)



shelf life

limited shelf life, expiry date on the label


HPLC: suitable
gas chromatography (GC): suitable

Featured Industry

Cleaning Products
Food and Beverages
Personal Care



SMILES string




InChI key


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General description

Indigo carmine (IC), a synthetic indigoid dye, belongs to the class of food dyes used to impart colorless foodstuffs a more characteristic appearance as well as to change the original color, texture of the food products and maintain natural color during processing and storage of food products.
This product is provided by Sigma-Aldrich, as a neat standard for the precise quality control of food products. In the European Union, E numbers are used as codes for food color additives. E numbers 100-199 include not only artificial food colors derived from petroleum, but also natural additives originating from sources such as vegetables, insects or mixtures made from natural foodstuffs. IC is widely used in a variety of food products including fruit juices, bread, smoked fish, sweets, tomatoes, catsup, dairy, skim milk products, etc.


Refer to the product′s Certificate of Analysis for more information on a suitable instrument technique. Contact Technical Service for further support.
Indigo carmine may be used as a test material to investigate its interaction with the calf thymus DNA in physiological buffer (pH 7.4) with the use of ethidium bromide (EB) dye as a fluorescence probe by spectroscopic studies. It may be used as an analytical reagent for spectrophotometric determination of pantoprazole sodium sesquihydrate (PNT) in pure form and dosage forms using a bromide-bromide mixture. IC may also be used as an analytical reference standard for the quantification of the analyte in food products using microemulsion electrokinetic chromatography (MEEKC).


Bottomless glass bottle. Contents are inside inserted fused cone.


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Signal Word


Hazard Statements


NONH for all modes of transport

WGK Germany


Certificate of Analysis

Certificate of Origin

Spectroscopic studies of DNA interactions with food colorant indigo carmine with the use of ethidium bromide as a fluorescence probe
Ma Y, et al.
Journal of Agricultural and Food Chemistry, 60(43), 10867-10875 (2012)
Determination of food colorants by microemulsion electrokinetic chromatography
Huang Y-H, et al.
Electrophoresis, 26(4-5), 867-877 (2005)
Sensitive spectrophotometric methods for the determination of pantoprazole sodium in pharmaceuticals using bromate-bromide, methyl orange and indigo carmine as reagents
Basavaiah K and Kumar ARU
Indian Journal of Chemical Technology, 14, 611-615 (2007)
Tsuneo Oyama
Digestive endoscopy : official journal of the Japan Gastroenterological Endoscopy Society, 25 Suppl 1, 7-12 (2013-03-27)
The indication of endoscopic submucosal dissection for Barrett's esophageal adenocarcinoma (BEA) is superficial BEA without lymph node metastasis. The characteristic endoscopic findings of superficial BEA are elevation, depression, and color change. Indigocarmine spreading is useful for the diagnosis of lateral...
Christian Gómez-Solís et al.
Journal of hazardous materials, 217-218, 194-199 (2012-04-03)
Indigo carmine and methylene blue dyes in aqueous solution were photodegraded using SiC-TiO(2) catalysts prepared by sol-gel method. After thermal treatment at 450°C, SiC-TiO(2) catalysts prepared in this work showed the presence of SiC and TiO(2) anatase phase. Those compounds...
Separation of Tartrazine; Amaranth; Indigo carmine; New Coccine; Sunset Yellow FCF; Allura Red AC; Fast Green FCF; Erioglaucine disodium salt; Erythrosin B sodium salt; Phloxine B; Rose bengal
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