May–Grünwald stain

May–Grünwald stain is a histological stain used in histopathology and cytology for the visualization of cell structures, particularly blood cells. It is a Romanowsky stain, which is a class of artificial dyes used in biological staining. May–Grünwald stain is primarily used in the examination of blood smears and bone marrow specimens. It is named after its inventors, Gustav May and Paul Grünwald.

Composition

The May–Grünwald stain is composed of methylene blue and eosin in methanol. The methylene blue is a basic dye that stains acidic, or basophilic, components of the cells, such as the nuclei and some granules, blue. Eosin is an acidic dye that stains basic, or eosinophilic, components, such as cytoplasm, red or pink.

Procedure

The staining procedure involves fixing air-dried smears of the specimen in pure methanol, followed by staining with the May–Grünwald solution. After a specified time, the slides are then diluted with a buffered solution, which allows for the differentiation of the stain. The slides are then washed, dried, and can be examined under a microscope.

Applications

May–Grünwald stain is widely used in the examination of peripheral blood smears and bone marrow specimens. It allows for the differentiation of various types of blood cells, which is crucial in the diagnosis of diseases such as anemia, leukemia, and other blood disorders. It is also used in the study of the morphology of cells in other bodily fluids.

Advantages and Limitations

One of the main advantages of the May–Grünwald stain is its ability to provide clear differentiation of cell types based on their staining properties. However, the quality of the staining can be affected by the age of the methanol and the precise timing of the staining process. Moreover, interpretation of the results requires significant expertise in hematology.

See Also

• Giemsa stain
• Wright's stain
• Leishman stain
• Histology
• Cytology