Acid fuchsin

A red acid dye used in histology and microbiology

Acid fuchsin is a red acid dye that is widely used in histology and microbiology for staining purposes. It is a member of the fuchsine family of dyes and is known for its ability to bind to tissue components, making it a valuable tool in the visualization of cellular structures.

Chemical properties

Acid fuchsin is a complex compound that belongs to the triphenylmethane dye family. It is characterized by its bright red color and its ability to form salts with acidic groups. The dye is soluble in water and alcohol, which makes it versatile for various staining techniques.

Applications in histology

In histology, acid fuchsin is commonly used in the Masson's trichrome stain, where it stains cytoplasm, muscle, and collagen fibers. This staining technique is particularly useful for distinguishing between different types of connective tissue.

Masson's trichrome stain

Masson's trichrome is a three-color staining protocol that uses acid fuchsin to provide contrast between muscle tissue and collagen. The dye binds to the cytoplasm and muscle fibers, giving them a red appearance, while other components are stained with different dyes to provide a full spectrum of colors.

Applications in microbiology

In microbiology, acid fuchsin is used in the Ziehl-Neelsen stain, a method for identifying acid-fast bacteria such as Mycobacterium tuberculosis. The dye penetrates the waxy cell wall of these bacteria, allowing them to be visualized under a microscope.

Ziehl-Neelsen stain

The Ziehl-Neelsen stain is a differential staining technique that uses acid fuchsin as a counterstain. After the primary stain, carbol fuchsin, is applied, acid fuchsin is used to provide contrast, highlighting the presence of acid-fast organisms against a blue or green background.

Safety and handling

As with many chemical dyes, acid fuchsin should be handled with care. It is important to use appropriate personal protective equipment (PPE) such as gloves and goggles when working with the dye to prevent skin and eye irritation. Proper disposal procedures should be followed to minimize environmental impact.

Related pages

• Histology
• Microbiology
• Staining (biology)
• Fuchsine

Gallery

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  Chemical structure of acid fuchsin