CAS No. 7240-90-6
Batch:
Purity:99.91
Chemical Structure
Check the
X-GAL
product page for in-depth specifications, including solubility, stock solutions, MOA, and working concentrations.
| IUPAC Name | (2S,3R,4S,5R,6R)-2-[(5-bromo-4-chloro-1H-indol-3-yl)oxy]-6-(hydroxymethyl)oxane-3,4,5-triol | |
|---|---|---|
| CAS Number | 7240-90-6 | |
| Molecular Formula |
C14H15BrClNO6 |
|
| Molecular Weight (MW) | 408.63 | |
| SMILES | C1=CC(=C(C2=C1NC=C2OC3C(C(C(C(O3)CO)O)O)O)Cl)Br | |
| InChIKey | OPIFSICVWOWJMJ-AEOCFKNESA-N |
X-Gal (BCIG) is a chromogenic substrate for β-galactosidase. Cleavage of X-Gal by β-galactosidase yields galactose and an insoluble 5-bromo-4-chloro-3-hydroxyindole intermediate, which dimerizes and oxidizes to form an intense blue precipitate. This reaction enables visual monitoring of gene expression, detection of lacZ reporter activity, and blue-white selection of recombinant bacterial colonies during molecular cloning procedures. [1]
Batch:
All in vitro solubility values are batch-tested experimental data (non-literature values).
| Solvent | Solubility & Note |
|---|---|
| DMF | 100 mg/mL |
| DMSO |
82 mg/mL
(200.67 mM)
(Moisture-contaminated DMSO may reduce solubility. Use fresh, anhydrous DMSO. The recommended stock concentration is 10 mM in DMSO.) |
| Water | Insoluble |
Q: Why does a DMSO stock precipitate in media/saline?
A: It is caused by unheated aqueous media (supersaturation), local solvent shock, or incorrect mixing sequence.
How to fix it?
- Preheat media/saline to 37°C.
- Mix rapidly (pipette/vortex) upon addition.
- For complex mixes, always add the aqueous phase last.
- Re-dissolve minor precipitates with a 37°C water bath and sonication (≤30 min).
Note: Technical data last updated: Sep 1, 2026.