Changes

β-D-galactopyranoside, C19H21O9Na, MW 416.35,  MDL Number MFCD03458481.

β-D-galactopyranoside, C19H21O9Na, MW 416.35,  MDL Number MFCD03458481.

S-Gal®, sodium salt is a patented water-soluble, autoclavable chromogenic substrate for β-galactosidase that is designed to replace X-Gal in blue-white selection of recombinant bacterial colonies with the lac+ phenotype. Caution: For black color development to occur, ferric ion must be present. Although we recommend ferric ammonium citrate (500 mg/L of media), other ferric compounds can be used to provide this requirement, depending upon your particular system.  From [https://www.sigmaaldrich.com/catalog/product/sigma/s7313?lang=en&region=US Sigma-Aldrich site].

S-Gal®, sodium salt is a patented water-soluble, autoclavable chromogenic substrate for β-galactosidase that is designed to replace X-Gal in blue-white selection of recombinant bacterial colonies with the lac+ phenotype. Caution: For black color development to occur, ferric ion must be present. Although we recommend ferric ammonium citrate (500 mg/L of media), other ferric compounds can be used to provide this requirement, depending upon your particular system.  From [https://www.sigmaaldrich.com/US/en/product/sigma/s7313 Sigma-Aldrich site].