Bouin's solution

Bouin's solution is a histological fixative solution used in the preparation of tissue samples for examination under a microscope. Named after French histologist Pol Bouin, it is particularly effective for the fixation of delicate tissues and structures, such as the gastrointestinal tract and reproductive system.

Composition

Bouin's solution is composed of picric acid, formaldehyde, and acetic acid. The typical formulation includes 75 parts saturated aqueous picric acid, 25 parts formaldehyde (37-40%), and 5 parts glacial acetic acid. The solution is usually prepared fresh, as it can degrade over time, particularly if exposed to light or heat.

Use

In histology, Bouin's solution is used as a fixative, a substance that preserves the structure of the tissue being examined. It works by creating cross-links between proteins in the tissue, which stabilizes the structure and prevents degradation. Bouin's solution is particularly effective for tissues that are delicate or difficult to preserve, such as the gastrointestinal tract and reproductive system.

The tissue sample is typically immersed in Bouin's solution for a period of time, usually overnight. The solution penetrates the tissue and reacts with the proteins to form a stable, fixed sample that can be further processed and examined under a microscope.

Advantages and Disadvantages

One of the main advantages of Bouin's solution is its ability to preserve delicate tissues and structures. It also enhances the staining of certain tissue components, such as nuclei and connective tissue, making them easier to see under the microscope.

However, Bouin's solution has some disadvantages. It can cause shrinkage of the tissue, which can distort the structure. It can also be hazardous to handle, as it contains picric acid, which is a powerful explosive when dry. Therefore, care must be taken in its storage and disposal.

See Also

• Histology
• Fixative (histology)
• Picric acid
• Formaldehyde
• Acetic acid