What is the purpose of adding methylene blue to the specimen?

Methylene blue is commonly used as a staining agent in microscopy to enhance the visibility of cellular structures within a specimen. It binds to nucleic acids and certain proteins, allowing for better contrast against the background, which aids in identifying and distinguishing various cellular components. Additionally, methylene blue can help highlight live versus dead cells, as viable cells may retain the dye differently compared to non-viable ones. Overall, its primary purpose is to facilitate clearer observation and analysis of biological samples.