X-GAL (5-bromo-4-chloro-3-indolyl-β-D-galactoside), consisting of galactose linked to a substituted indole, is a histochemical substrate for β-galactosidase. This substrate yields a blue precipitate upon hydrolysis, making it suitable for use in immunoblotting or immunocytochemical assays., and thus is widely used a chromogenic β-galactosidase substrate. β-galactosidase cleaves X-gal and produce an insoluble blue compound, which is detectable. X-gal is often used in molecular biology to test for the presence of an enzyme, β-galactosidase. It is also used to detect activity of this enzyme in histochemistry and bacteriology. X-gal is one of many indoxyl glycosides and esters that yield insoluble blue compounds similar to indigo dye as a result of enzyme-catalyzed hydrolysis.

纯度：≥98%

CAS：7240-90-6