Signage staining that highlights nuclei, cytoplasm and collagen fibers by selectively collecting dyes to get an idea of the general topography of a tissue.
Implementation time, about three minutes for fast HES, seven minutes for direct HES, 35 minutes with dewaxing for standard HES.
Trichromic method that successively act three dyes.
An aqueous solution of hematoxylin (nuclear), an aqueous solution of eosin (cytoplasmic) and an alcoholic solution of saffron (collagen). Nuclear staining is progressive. After hematoxylin (Meyer), a rapid differentiation in a saturated lithium carbonate solution (lithium water) or simply running water is carried out in order to blue the nuclei and facilitate the fixing of dyes.
Cytoplasmic staining is regressive. After eosin, the excess is rinsed with running water, a differentiation is carried out in successive baths of ethanol to absolute ethanol. The passages in ethanol prepare the action of saffron which diffuses throughout the fabric thanks to an absorption phenomenon.
At the end of coloring, the slides must be immersed in a solvent bath (toluene, xylene) for assembly. Under no circumstances should they be allowed to air dry because dyes may precipitate in the fabric.