• Molecular biology grade

 • RNase, DNase and Protease free

X-Gal (5-Bromo-4-Chloro-3-Indolyl-β-D-galactopyranoside) is a β-galactosidase chromogenic substrate. In the presence of ß-galactosidase, X-Gal is hydrolyzed and yields a blue precipitate.
X-Gal is used for the identification and selection of galactosidase producing bacteria (bacteria Lac+); they produce blue colonies on agar medium. X-Gal is used at a 40 m g/ml concentration. It is soluble in dimethylformamide.