EOSINE YELLOW STAIN SOLUTION 2% W/V

Eosine Yellow Stain Solution 2% w/v is a staining solution for microscopic examination of biological specimens. It is often used as a counterstain to haematoxylin. It can also be of use in the monochrome staining of microorganisms.
Eosin is an acid dye that stains basic or eosinophilic cellular components, especially proteins with amino acid residues such as arginine and lysine. This reaction produces the characteristic pink to dark-red colour. It can also stain structures such as cytoplasm, collagen and muscle fibres. This helps to differentiate the various elements on microscopic examination.
It is an orange-red solution having a specific gravity of about 1.01 g per millilitre at 20°C. It meets the necessary suitability test for microscopy staining.
Proper specimen preparation is critical for obtaining consistent staining. Cell films should be fixed as soon as possible to preserve morphology. In the case of methanol fixation, the methanol must be essentially anhydrous, as water can influence the appearance of stained films. Slides must also be carefully cleaned to ensure that detergent residues do not interfere with red blood cell staining. Thick films may require careful staining to prevent excess stain residue or interference from lysed cell material.

Used as a staining solution and counterstain for microscopy, highlighting cellular proteins, cytoplasm, collagen, and muscle fibres in contrasting pink-red shades.