Gladstone Institutes Histology and Light Microscopy Core Massons Trichrome Protocol Massons trichrome is a three colour staining protocol used to identify cells and surrounding connective tissues. Often a Weigert nuclear counterstain is added. Most MT protocols produce red keratin and muscle, green collagen and bone, light red to pink cytoplasm and black cell nuclei. An iron haematoxylin (weigerts) is used to stain the nuclei, then the Briebrich scarlet (an acid dye) attaches to the acidophilic parts of the tissue, the phopho acid then removes the scarlet from the collagen leaving it open to staining with light green, or alternatively, aniline blue. Pretreatment of the dewaxed sections in Bouins or aqueous saturated picric acid increases the vibrancy and crispness of the colors in the resulting slide. Tissue: Formalin fixed paraffin embedded tissue or cryosections (with less resolution and quality), sectioned at 2-10m Controls: Skin, lung, intestine, stomach Solutions: Bouins Solution American Mastertech FXBOUGAL Or saturated (1.2%) aqueous picric acid Biebrich scarlet-acid fuchsin Stable for 6 months Biebrich scarlet 2.7g Acid fuchsin 0.3g diH 2 O 300ml Glacial acetic acid 3ml Phosphomolybdic - Phosphotungstic acid Stable for 6 months 26 Dec 2012 Massons Trichrome Page 1 of 4