Apex X-Gal is manufactured under the industry's most stringent quality control procedures to assure lot-to-lot consistency for reproducible results in your laboratory. Apex X-Gal (5-Bromo-4-chloro-3-indolyl-b-D-galactopyranoside) is a chromogenic substrate for b-galactosidase that turns blueupon hydrolysis. It is commonly used for blue/white screening of recombinants when using vectors that support alpha complementation of b-galactosidase. Formula: C14H15BrClNO6, Molecular Weight: 408.6, Purity: >99% by HPLC, Solubility 2% in DMF (N-N' dimethyl formamide), Structure confirmed using 1H-NMR. Store at 4ºC; protect from light and humidity. For long term storage: -20ºC. C.A.S. R.N. [7240-90-6]