Bouin's solution lyses red blood cells and is excellent for which stain and preservation of soft delicate textures?

• A. Trichrome stain
• B. Gram stain
• C. Hematoxylin and eosin
• D. PAS stain

Answer: (A)

Bouin's solution is a picric acid–containing fixative that rapidly preserves tissue while lysing red blood cells. This combination helps keep soft, delicate textures intact and reduces blood masking, which is exactly what you want when you’re trying to differentiate subtle tissue components. Trichrome staining is designed to distinguish different tissue elements—collagen, muscle, and cytoplasm—by producing distinct colors (for example, collagen blue/green, muscle and cytoplasm pink/red). The excellent preservation and clearing of red cells provided by Bouin’s fixative gives crisp, clear separation of these components, making the trichrome stain especially effective.