Leishman stain is a high-grade reagent supplied by Micromaster. It is available in the form of a dark green powdered solid. It is based on a methanolic mixture of "polychromed" methylene blue (i.e. demethylated into various azures) and eosin. Bright light and heat oxidize the stain, especially when in aqueous solution and will cause precipitation of insoluble precipitates. Leishman stain should be kept in a tightly stoppered light opaque (e.g. amber) container in a cool dark place. It is stable if stored according to the recommended conditions. If exposed to excessive heat or in case of burning, it can generate hazardous decomposition products like carbon monoxide, carbon dioxide, hydrogen bromide and nitrogen oxides. Leishman stain is incompatible with oxidising agents.

• CAS No. 12627-53-1
• Quantity provided: 100 g/pack
• Molecular formula: C₆H₅NO₅
• Molecular weight: 171.038 g/mol

Leishman stain is used in microbiology for staining blood smears. It is normally used to differentiate and identify leucocytes, malaria parasites, and trypanosomas. It is one of the best stains used to observe peripheral blood smear under the microscope. Leishman stain generally shows the brilliant violet color of the nucleus and the neutrophil granules for which differential count becomes convenient and makes the quality of staining better than the stains that are simple methylene blue and Eosin based which does not produce enough contrast between the cytoplasm and the nucleus.