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saf·ra·nin O(saf'ră-nin), [C.I. 50240]
A mixture of dimethyl- and trimethylphenosafranin chloride, a basic red dye that exhibits orange metachromasia; used in histology as a nuclear stain, in microbiology as a counterstain in the Gram method, and to demonstrate enterochromaffin.
safranin, safranin O
A histological stain used in microscopy to highlight cell nuclei by counterstaining them red. It is used for many purposes, including the gram staining of body fluid specimens.