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C6277

Sigma-Aldrich

Congo Red

certified by the Biological Stain Commission, BioXtra

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Synonym(s):
Congo Red 4B, Cosmos Red, Cotton Red B, Cotton Red C, Direct Red 28, Direct Red R, Direct Red Y
Empirical Formula (Hill Notation):
C32H22N6Na2O6S2
CAS Number:
Molecular Weight:
696.66
Colour Index Number:
22120
Beilstein/REAXYS Number:
3894858
EC Number:
MDL number:
PubChem Substance ID:

grade

certified by the Biological Stain Commission

Quality Level

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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1 of 4

This Item
C6767S4261S4136
Congo Red certified by the Biological Stain Commission, BioXtra

C6277

Congo Red

Congo Red Dye content ≥35 %

C6767

Congo Red

Sudan IV certified by the Biological Stain Commission, BioXtra

S4261

Sudan IV

Sudan III BioXtra, certified by the Biological Stain Commission

S4136

Sudan III

application(s)

diagnostic assay manufacturing
hematology
histology

application(s)

diagnostic assay manufacturing
hematology
histology

application(s)

diagnostic assay manufacturing
hematology
histology

application(s)

diagnostic assay manufacturing
hematology
histology

solubility

H2O: 10 mg/mL

solubility

H2O: 1 mg/mL

solubility

-

solubility

toluene: 1 mg/mL, clear, red

form

powder

form

powder

form

powder

form

powder

storage temp.

room temp

storage temp.

room temp

storage temp.

room temp

storage temp.

room temp

composition

Dye content, ≥85%

composition

Dye content, ≥35%

composition

Dye content, ≥80%

composition

Dye content, ≥80%

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

signalword

Danger

Hazard Classifications

Carc. 1B - Repr. 2

Storage Class

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

wgk_germany

WGK 3

ppe

Eyeshields, Gloves, type P3 (EN 143) respirator cartridges


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Efficient imaging of amyloid deposits in Drosophila models of human amyloidoses.
Berg I, et al.
Nature Protocols, 5, 935-935 (2010)
Alejandro Llanos-Chea et al.
Journal of pediatric gastroenterology and nutrition, 68(4), 509-516 (2018-11-13)
Enteric bacterial pathogens cause diarrheal disease and mortality at significant rates throughout the world, particularly in children younger than 5 years. Our ability to combat bacterial pathogens has been hindered by antibiotic resistance, a lack of effective vaccines, and accurate
Kinetic study and equilibrium isotherm analysis of Congo Red adsorption by clay materials.
Vimonses V, et al.
Chemical Engineering Journal, 148, 354-364 (2009)
Use of Congo red-polysaccharide interactions in enumeration and characterization of cellulolytic bacteria from the bovine rumen.
Teather RM and Wood PJ
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Long-term treatment of thalidomide ameliorates amyloid-like pathology through inhibition of ?-secretase in a mouse model of Alzheimer's disease.
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