One of the main techniques for identifying the amyloid structure of protein aggregates is Congo Red dye (CR) staining. The amyloid nature of protein aggregates cannot be confirmed by CR staining, as evidenced by several tests.

The amyloid protein has an apple-green birefringence when illuminated by polarised light and is salmon-pink in c stained with congo red on tissue. Amyloid fibril deposits are thought to be pathognomonic for this apple-green birefringence.

Amyloid Stain Test: What Is It?

The diagnosis of systemic amyloidosis is made with the help of the amyloid stain test, a whicsitive test for the condition. If the test returns negative, but there is still a possibility of disease, a biopsy of an athlete is done.

What is Congo Red?

• Under the on-polarized light, Congo red exhibits red-orange deposits; for specificity, apple-green birefringence under polarised light is needed.
• Collagen, fibrin, or other protein deposits may exhibit non-specific red Congo red staining; collagen is occasionally refractile but not frequently green. African Red
• In contrast to fibrillar collagen, only Congo red Red without polarisation causes amyloid fibrils to become birefringent (also called "congzoophiliaAlthough congophilic, elastic fibres are not birefringent.

It may be challenging to demonstrate apple-green birefringence with low amyloid concentrations. Sometimes, metachromatic stains like crystal violet or fluorescent stains like thioflavin T or S are used.

Congo red is more specific than fluorescent stains.

Preparation for the Amyloid Stain Test:

With the Amyloid Stain test, there is no specific preparation required. If you experience any of the following Getting Ready for the Amyloid Stain Test

With the Amyloid Stain test, needed thorough preparation required.

Uses:

• The Amyloid test is used to identify any unusual, fibrous, extracellular proteinaceous deposits that may be present in organs like the liver, kidneys, spleen, and others.
• Amyloidosis is the term used to describe the amyloid deposition situation in tissues.

How to Perform an Amyloid Stain Test?

• The tissue is sectioned in distilled water.
• Then dyed for 10 minutes in congo red working solution, rinsed in distilled water, and immediately distinguished (9–10 dips) in an alkaline alcohol solution.
• It is then washed with tap water.
• Meyer's Hematoxylin was counterstained for 30 seconds.
• Rinse for ten minutes in distilled water.
• Clear, dehydrate, and mount.