Van Gieson's microfuchsin is a histological staining solution used primarily to visualize collagen fibers in tissue sections. It stains collagen fibers intensely red, while other tissue structures and cells are generally not stained or take on a different color.

The Van Gieson stain is often used in combination with other stains, such as resorcinol-fuchsin to visualize elastic fibers and Weigert's hematoxylin or another hemalaun to stain cell nuclei. This combination allows differentiated visualization of various tissue components in tissue sections.

Applications for Van Gieson's picrofuchsin staining include the study of vessel wall damage, arteriosclerotic changes, fibrosis, inflammation, and various connective tissue diseases. Specific staining of collagen fibers allows pathologists to identify subtle changes in the structure and composition of connective tissue, which are important for diagnosing and understanding various diseases.