Methyl Green, also known as Double Green SF, is a basic dye, a green microcrystal or powder with metallic luster, molecular weight 608.78, molecular formula C27H35Cl4N3Zn.Methyl Green-Pyronin Stain (MGP) is a staining solution that stains the nucleus of the cells green or blue-green, and stains the plasma of the cells and the nucleus in the nucleus red or reddish-purple. nucleoli to red or reddish-purple. Methyl Green binds to DNA in the nucleus, thus staining the nucleus green or blue-green, and Pyronin binds to RNA in the cytoplasm or nucleolus, thus staining the cytoplasm and nucleolus red or reddish purple.

DNA nucleic acid and RNA nucleic acid staining solution (Methyl Green - Pyronin Staining Method) has been modified to be free of methanol, and stains the nucleus in tissue or cell staining, in which the methyl green has been purified to make it easier to stain, this staining solution can also be used with immunofluorescence staining or immunohistochemical staining, and 10 ml of the staining solution can stain up to 20 samples.