Eosin methylene blue (EMB, also known as "Levine's formulation") is a selective stain for Gram-negative bacteria.EMB contains dyes that are toxic to Gram-positive bacteria.
Eosin-methylene blue also known as Leishman stain is a Romanowsky-type dye, similar to Wright stain.Leishman stain is used in hematology and tropical medicine to differentiate and identify leukocytes, malarial parasites, and trypanosomes.