Sudan Black staining is used to demonstrate which tissue component?

• A. Adipose tissue
• B. Collagen
• C. Nuclei
• D. Muscle fibers

Answer: (A)

Sudan Black is a lipid-soluble dye, so it binds to lipids such as neutral fats and phospholipids, making lipid-rich areas dark. Adipose tissue, with adipocytes packed full of triglyceride droplets, is exactly what this stain highlights, allowing you to visualize fat more readily. Keep in mind that routine paraffin processing often removes lipids, so Sudan Black is typically used on frozen sections to demonstrate lipids effectively. Other structures are stained by different methods—collagen by special trichrome or picrosirius red, nuclei by hematoxylin, and muscle fibers by eosin-based stains—so the lipid-rich adipose tissue stands out with Sudan Black.