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C6277

Sigma-Aldrich

Congo Red

certified by the Biological Stain Commission, BioXtra

Synonym(s):

Congo Red 4B, Cosmos Red, Cotton Red B, Cotton Red C, Direct Red 28, Direct Red R, Direct Red Y

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About This Item

Empirical Formula (Hill Notation):
C32H22N6Na2O6S2
CAS Number:
573-58-0
Molecular Weight:
696.66
Colour Index Number:
22120
Beilstein:
3894858
EC Number:
209-358-4
MDL number:
MFCD00004028
UNSPSC Code:
12171500
PubChem Substance ID:
24892852

grade

certified by the Biological Stain Commission

Quality Level

200

product line

BioXtra

form

powder

composition

Dye content, ≥85%

mp

>360 °C (lit.)

solubility

H2O: 10 mg/mL

application(s)

diagnostic assay manufacturing
hematology
histology

storage temp.

room temp

SMILES string

[Na+].[Na+].Nc1c(cc(c2ccccc12)S([O-])(=O)=O)\N=N\c3ccc(cc3)-c4ccc(cc4)\N=N\c5cc(c6ccccc6c5N)S([O-])(=O)=O

InChI

1S/C32H24N6O6S2.2Na/c33-31-25-7-3-1-5-23(25)29(45(39,40)41)17-27(31)37-35-21-13-9-19(10-14-21)20-11-15-22(16-12-20)36-38-28-18-30(46(42,43)44)24-6-2-4-8-26(24)32(28)34;;/h1-18H,33-34H2,(H,39,40,41)(H,42,43,44);;/q;2*+1/p-2/b37-35+,38-36+;;

InChI key

IQFVPQOLBLOTPF-HKXUKFGYSA-L

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Application

Congo red has been used for the staining of β amyloid peptides.

Biochem/physiol Actions

Congo red is a benzidine-based anionic diazo dye. It is a histological dye which binds to many amyloid proteins and is used for the quantification of amyloid β-peptide aggregation. Congo red also interacts with β-D-glucans, polysaccharides containing continuous β-(1→4)-linked D-glucopyranosyl units and some hemicellulosic galactoglucomannans.

Suitability

Certified for use as a counterstain for alum based hematoxylin and in the Highman or the Churukian modification of Puchtler′s amyloid stain.

Pictograms

Health hazard
GHS08

Signal Word

Danger

Hazard Statements

H350 - H361d

Hazard Classifications

Carc. 1B - Repr. 2

Storage Class Code

6.1C - Combustible, acute toxic Cat.3 / toxic compounds or compounds which causing chronic effects

WGK

WGK 3

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Regulatory Listings

Regulatory Listings are mainly provided for chemical products. Only limited information can be provided here for non-chemical products. No entry means none of the components are listed. It is the user’s obligation to ensure the safe and legal use of the product.

EU REACH SVHC Candidate List

CAS No.

EU REACH Annex XVII (Restriction List)

CAS No.

Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

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