Description: Congo Red (Direct Red 28) is an azo dye. It binding been used as a diagnostic test for the presence of amyloid in tissue sections. Target: Others. Smiles: Nc(c1ccccc1c(S([O-])(=O)=O)c1)c1N=Nc(cc1)ccc1-c(cc1)ccc1N=Nc(cc(c1ccccc11)S([O-])(=O)=O)c1N.[Na+].[Na+]. References: Amornvit J, et al. A novel...

Sodium salt of benzidinediazo-bis-1-naphtylamine-4-sulfonic acid. CR is water soluble, yielding a red colloidal solution. It is used to stain cytoplasm and erythrocyte stain in histology.