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5-bromo-4-chloro-3-indolyl-β-D-glucuronide sodium salt (X-GlcA), a colorless substrate for β-glucuronidase enzyme, generates a blue color at the end of the reaction.
B 6124 (OTTO) 5-Bromo-4-chloro-3-indolyl β-D-glucuronide sodium salt, ≥98% Cas 129541-41-9 - used as a component in β-glucuronidase (GUS) assay buffer for histochemical GUS assay.