Purple-β-D-Gal is a chromogenic β-galactosidase substrate. Intracellular enzymatic hydrolysis of Purple-β-D-Gal generates free indoxyl molecules, which undergo in situ oxidation and subsequent dimerization to produce chromogenic, water-insoluble, indigo precipitates. Purple-β-D-Gal can be used for the detection of β-galactosidase activity.IC50 & Target:β-galactosidase