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the act of spotting or staining something

the act of spotting or staining something

of Stain

The marking of biological material with a dye or other reagent for the purpose of identifying and quantitating components of tissues, cells or their extracts.

The act of impregnating a substance, especially a tissue under microscopic examinations, with pigments so as to distinguish the various structures of which it is composed. The principal s's used in microscopy are hematoxylin, carmin, ammonia carmin, picrocarmin, silver nitrate, gold chlorid, and the various anilin dyes (fuchsin, eosin, vesuvin, auramin, safranin, fluorescin, methylene blue, gentian violet, methyl violet, malachite green, etc.).