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Related to toluidine blue: methylene blue, toluidine blue dye
an antiheparin compound, used also as a biological stain. Called also tolonium chloride.
toluidine blue test
a screening test for mucopolysaccharidosis, e.g. Hurler's syndrome; filter paper impregnated with toluidine blue turns blue when moistened with urine containing excessive amounts of chondroitin sulfuric acid.