| CAS No. | 501-94-0 |
| Molecular Formula | C8H10O2 |
| Molecular Weight | 138.16 g/mol |
| Category | Pharmacopoeial Impurity Standards / EP Impurities |
| Availability | In Stock |
Compared with other compounds in its class, the molecular weight of 138.16 g/mol gives Metoprolol EP Impurity G distinctive chromatographic separation conditions and mass-spectrometry parameter settings.
CATO supplies Metoprolol EP Impurity G (CAS 501-94-0), a pharmacopoeial impurity reference standard (molecular formula C8H10O2, MW 138.16 g/mol) used for the identification and quantification of trace impurities in APIs.
Based on its molecular formula C8H10O2, Metoprolol EP Impurity G contains a carboxylic acid group, a hydroxyl group, an ether linkage, an aromatic ring system; these features give the compound characteristic absorption bands in UV spectroscopy. The molecular weight of 138.16 g/mol is directly relevant to the identification of the molecular ion in mass spectrometry. The aromatic system may exhibit native fluorescence, enabling detection with a fluorescence detector (FLD).
This reference standard supports related-substances testing and method development in line with ICH Q3A/Q3B guidance on impurity control, and is suitable for system suitability testing and forced-degradation studies.
The assigned purity is verified by mass-balance and quantitative NMR (qNMR) approaches, with the expanded uncertainty reported at a 95% confidence level (k=2). Batch homogeneity and stability are independently assessed for every lot.
| Molecular Formula | C8H10O2 |
| Molecular Weight | 138.16 g/mol |
| Purity | >95% |
| Storage | Store at 2-8°C |
| Solubility (reference) | Soluble in methanol, acetonitrile, DMSO, water (slightly soluble) |
| Stability | May oxidize slowly on prolonged air exposure |
| Degree of Unsaturation (DBE) | 4.0 |
| UV Absorption | UV-absorbing |
| Structural Features | Aromatic ring present |
| CAS Registry Year (est.) | 1957 |