Which staining technique is shown in the image?

• A. Feulgen
• B. Hematoxylin and Eosin
• C. Periodic acid–Schiff
• D. Wright

Answer: (A)

The image shows magenta-stained nuclei, which is the hallmark of the Feulgen reaction. This staining is DNA-specific: after acid hydrolysis, the deoxyribose in DNA forms aldehyde groups that react with Schiff reagent to produce a magenta color. Because it targets DNA, nuclei alone glow in that distinctive hue, providing precise visualization of nuclear material without staining most cytoplasmic components.

Other stains have broader targets and produce different color patterns. Hematoxylin and eosin yields blue-purple nuclei with pink cytoplasm, not the pure magenta nuclear stain seen here. PAS highlights carbohydrates and glycoproteins in magenta but often emphasizes cytoplasmic and extracellular structures like basement membranes, not just nuclei. Wright stain colors blood cells in a range of hues depending on cell type and granules, not producing the uniform magenta nuclei characteristic of Feulgen.