Stains are used in microscopy to help view bacteria, which are normally colorless and hard to see in their natural state even with a microscope.
Methylene Blue is a popular alkaline stain used to view microscopic life in brilliant color. It helps make cells show up against their background, where their shape can help you determine what they are (their morphology).
It's attraction to acid makes it particularly useful for viewing animal cells since these cell nuclei contain deoxyribonucleic acid (DNA). It’s also used in aquariums to guard against fungal infections in fish.
Eosin Y Stain is a reversible, fluorescent red, acidic dye, commonly used in hospital histology labs. Eosin's most important medical uses are in blood and bone-marrow testing, including the PAP smear. It can also test for protein in plant, animal and blood specimens. This stain is a valid substitute for Congo Red or Neutral Red and is frequently used as a counter-stain to Haematoxylin in H&E staining.
Both employ the same process, as follows:
For best results, follow the sequence below: