Medical Dictionary

Congo red

noun \ˌkäŋ-(ˌ)gō-ˈred\

Medical Definition of CONGO RED

:  an azo dye C32H22N6Na2O6S2 that is red in alkaline and blue in acid solution and that is used in a number of diagnostic tests and especially for the detection of amyloidosis since the injected dye tends to be retained by abnormal amyloid deposits

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