Hollande's solution is a modification of Bouin's and uses which compound to stabilize red blood cells?

• A. Copper acetate
• B. Sodium acetate
• C. Calcium chloride
• D. Magnesium sulfate

Answer: (A)

Hollande's solution is a modification of Bouin's fixative that adds a copper salt to stabilize red blood cells during fixation. Bouin's fixative, which contains picric acid, formaldehyde, and acetic acid, preserves tissues well but can cause red blood cells to lyse or distort because of the acetic acid and the fixative environment. Introducing copper acetate provides a stabilizing effect on red blood cell membranes, helping to maintain their morphology and improving subsequent staining. The other salts listed don’t provide this specific stabilization effect in the Hollande formulation, so copper acetate is the essential component for preserving RBCs.