Congo Red *UltraPure grade* *CAS 573-58-0*
Congo red (CR) is the 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. Apple-green birefringence of CR stained preparates under polarized light is indicative for the presence of amyloid fibrils. Early diagnosis and classification of amyloid deposition and differentiation from other fibrillar deposits rely on routine CR-based histochemistry. This histology assay is widely used for the characterization of in vitro amyloid fibrils. In addition, CR is also used for fluorimetric examination of amyloid fibrils. Compared to CR in bright light CR fluorescence is simple to perform and more pronounced. Although not widely used, the CR fluorimetric method for detecting amyloid is simple to use with a high specificity and sensitivity, and may be applied successfully to frozen sections.
Calculators
Common stock solution preparation
Table 1. Volume of Water needed to reconstitute specific mass of Congo Red *UltraPure grade* *CAS 573-58-0* to given concentration. Note that volume is only for preparing stock solution. Refer to sample experimental protocol for appropriate experimental/physiological buffers.
0.1 mg | 0.5 mg | 1 mg | 5 mg | 10 mg | |
1 mM | 143.542 µL | 717.71 µL | 1.435 mL | 7.177 mL | 14.354 mL |
5 mM | 28.708 µL | 143.542 µL | 287.084 µL | 1.435 mL | 2.871 mL |
10 mM | 14.354 µL | 71.771 µL | 143.542 µL | 717.71 µL | 1.435 mL |
Molarity calculator
Enter any two values (mass, volume, concentration) to calculate the third.
Mass (Calculate) | Molecular weight | Volume (Calculate) | Concentration (Calculate) | Moles | ||||
/ | = | x | = |
Spectrum
Open in Advanced Spectrum Viewer
Product family
Name | Excitation (nm) | Emission (nm) |
Amplite® Red | 571 | 584 |
Nile Red *CAS 7385-67-3* | 559 | 635 |
LysoBrite™ Red | 576 | 596 |
Amylite™ Red | 485 | 671 |
References
View all 53 references: Citation Explorer
The effects of sodium sulfate, glycosaminoglycans, and Congo red on the structure, stability, and amyloid formation of an immunoglobulin light-chain protein
Authors: McLaughlin RW, De Stigter JK, Sikkink LA, Baden EM, Ramirez-Alvarado M.
Journal: Protein Sci (2006): 1710
Authors: McLaughlin RW, De Stigter JK, Sikkink LA, Baden EM, Ramirez-Alvarado M.
Journal: Protein Sci (2006): 1710
Acetylcholinesterase-amyloid-beta-peptide interaction: effect of Congo Red and the role of the Wnt pathway
Authors: Inestrosa NC, Alvarez A, Dinamarca MC, Perez-Acle T, Colombres M.
Journal: Curr Alzheimer Res (2005): 301
Authors: Inestrosa NC, Alvarez A, Dinamarca MC, Perez-Acle T, Colombres M.
Journal: Curr Alzheimer Res (2005): 301
Alzheimer's beta-amyloid: insights into fibril formation and structure from Congo red binding
Authors: Inouye H, Kirschner DA.
Journal: Subcell Biochem (2005): 203
Authors: Inouye H, Kirschner DA.
Journal: Subcell Biochem (2005): 203
Improved detection of amyloid in fat pad aspiration: an evaluation of Congo red stain by fluorescent microscopy
Authors: Giorgadze TA, Shiina N, Baloch ZW, Tomaszewski JE, Gupta PK.
Journal: Diagn Cytopathol (2004): 300
Authors: Giorgadze TA, Shiina N, Baloch ZW, Tomaszewski JE, Gupta PK.
Journal: Diagn Cytopathol (2004): 300
Congo red populates partially unfolded states of an amyloidogenic protein to enhance aggregation and amyloid fibril formation
Authors: Kim YS, R and olph TW, Manning MC, Stevens FJ, Carpenter JF.
Journal: J Biol Chem (2003): 10842
Authors: Kim YS, R and olph TW, Manning MC, Stevens FJ, Carpenter JF.
Journal: J Biol Chem (2003): 10842
Page updated on October 12, 2024