Science Fair Project Encyclopedia
Congo red
Congo red is the sodium salt of benzidinediazo-bis-1-naphtylamine-4-sulfonic acid. It is a secondary diazo dye. Congo red is water soluble, yielding a red colloidal solution. It is used for the dyeing of cotton, despite its sensitivity to light and acids. In biochemistry and histology, congo red is used to stain microscopic preparates, especially as a cytoplasm and erythrocyte stain. Green birefringence of congo red stained preparates under polarized light is indicative for the presence of amyloid fibrils.
Due to a color change from red to blue at pH 3.0-5.2, congo red can be used as a pH indicator.
10-26-2009 08:16:03
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details