Is Chromotrope 2R vegan?

Chromotrope 2R

Vegan

Chromotrope 2R is a synthetic azo dye used as a histological stain and acid-base indicator, classified as Acid Red 29 in the Colour Index. It is also known as Carmoisine 6R and is used in microscopy for staining connective tissue.

Also known as Acid Red 29, Carmoisine 6R
CAS number 4197-07-3
CI number CI 16570
Last reviewed 3 June 2026

Sources

Classifications are made to the best of our knowledge based on available scientific and regulatory sources. We cannot guarantee the accuracy of every entry, errors in the sources we draw from can always occur. This tool also cannot account for cross-contamination, which depends entirely on individual suppliers and producers. If you believe a classification is incorrect, you can report an issue.