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Congo red

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noun Con·go red \ˈkäŋ-(ˌ)gō-\

Definition of Congo red

  1. :  an azo dye C32H22N6Na2O6S2 that is red in alkaline and blue in acid solution and that is used especially as an indicator and as a biological stain



Origin of congo red

Congo, territory in Africa


First Known Use: 1885


Medical Dictionary

Congo red

play
noun Con·go red \ˌkäŋ-(ˌ)gō-ˈred\

Medical Definition of Congo red

  1. :  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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