Visualization of amyloids is important in certain neurodegenerative pathologies such as Alzeimer's disease, Creutzfeld-Jakob disease or Bovine spongiform encephalopathy.

Highman's Congo Red staining is based on 3 reagents, including a red congo solution and an alkaline solution as a differentiation medium to prevent non-specific staining of cellular substances.

Using alkaline alcoholic solvents, as in this technique, has the effect of suppressing electrochemical staining of other tissue components. The use of an alkaline solution improves the hydrogen bonding and thus improves the selectivity for amyloid. The amyloid deposits appear green under polarized light.

Here are some examples of colorations obtained with Highgo (in white light) staining with Congo red:

• Amyloid, elastin fibers, keratin and eosinophilic granules: Orange - Red
• Nuclei: Blue