Congo red

A brownish-red powder, C₃₂H₂₂N₆Na₂O₆S₂, used in medicine and as a dye, indicator, and biological stain.

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Congo red

(Elements & Compounds) a brownish-red soluble powder, used as a dye, a diagnostic indicator, a biological stain, and a chemical indicator. Formula: C32H22N6O6S2Na2

Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

Con′go red′

a water-soluble powder, C₃₂H₂₂O₆N₆S₂Na₂, used chiefly as a dye, biological stain, and chemical indicator.

[1880–85]

ThesaurusAntonymsRelated WordsSynonymsLegend:

Noun

congo red - a red-brown azo dye especially as a chemical pH indicator (congo red is red in basic and blue in acidic solutions)

solution - a homogeneous mixture of two or more substances; frequently (but not necessarily) a liquid solution; "he used a solution of peroxide and water"

acid-base indicator - an indicator that changes color on going from acidic to basic solutions

azo dye - any dye containing one or more azo groups

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References in periodicals archive

Congo red staining for amyloid and IgG subclass was negative.

Henoch-Schonlein purpura nephritis associated with monoclonal gammopathy of renal significance: a case report

A phenotypic method was used, according to Freeman et al., (13) by the Congo red agar (CRA) medium.

Frequency of icaA and icaD determinants and biofilm formation among coagulase-negative staphylococci associated with nasal carriage in neonatal intensive care units

Most of these are phenotypic methods which include Congo red assay (CRA), Air liquid interface (ALI), tissue culture plate (TCP) method and Microtiter plate assay (MTPA).

Assessment of biofilm formation by pseudomonas aeruginosa and hydrodynamic evaluation of microtiter plate assay

Subsequently, Congo red and crystal violet dyes were applied; and it was observed under the polarized light that areas with amorphous matter accumulation rendered 'apple green reflections with Congo red (Figure 4).

Localized Breast Amyloidosis

Pathology returned as a benign polypoid mucosa containing deposits consistent with amyloid, but with negative Congo red staining for amyloidosis.

An unusual case of persistent dysphagia

The presence of amyloid was confirmed by Congo red staining, showing apple-green birefringence under polarized light, as well as by a Thioflavin S stain under fluorescence microscopy, which was positive (Figure 3).

Primary localized ureteral amyloidosis mimicking urothelial carcinoma

Biofilm formation and dispersion studies, Congo red agar assay

In-vitro Growth Inhibition and Biofilm Dispersion of Caries causing Streptococcus mutans by the Natural Extracts of Soil Streptomyces

The microtitration plate method was optimized using computational fluid dynamics and compared with the Congo red assay.

Role of Intracellular Adhesion icaAD and agr genes in Biofilm Formation in Clinical S. aureus Isolates and Assessment of Two Phenotypic Methods

This study proved selective adsorption of cationic methylene blue (MB) and anionic Congo red (CR) in PA / CFO nanocomposites [13].

Synthesis of Fe3O4 Magnetic Nanoparticles and Investigation of Removal Capacity

Histopathology with Congo red showed positive green-apple birefringence under polarized light, consistent with amyloid deposition and a diagnosis of amyloidosis of the urinary bladder (Fig.

Images in urology: Localized primary amyloidosis of the urinary bladder

After staining with Congo red, the sample showed diffuse amyloid apple-green deposits when viewed under polarized light (Fig.

Primary systemic amyloidosis with skin and cardiac involvement: a case report