Table 1.
Comparison of USP method with UPLC and BP-HPLC methodsa
| Condition | USP method for impurities (vancomycin hydrochloride for injection) | BP method for related substances (vancomycin intravenous infusion) | OTR-UPLC purity method |
|---|---|---|---|
| Instrument | Specific instrument not provided | Specific instrument not provided | Waters Acquity UPLC system |
| Column | L1 (4.6 by 250 mm, 5 μm) | End-capped ODS silica gel (4.6 by 250 mm, 5 μm), e.g., Hypersil ODS | Waters BEH C18 (2.1 by 100 mm, 1.7 μm with Waters BEH C18 (2.1 by 5 mm, 1.7 μm) guard column |
| Temp | Does not state in method | Ambient | 35°C |
| Mobile phase A | 92:7:1 (pH 3.2 TEA buffer-acetonitrile-THF) | 92:7:1 (pH 3.2 TEA buffer-acetonitrile-THF) | 5 mM KH2PO4 (pH 3.2) |
| Mobile phase B | 70:29:1 (pH 3.2 TEA buffer-acetonitrile-THF) | 70:29:1 (pH 3.2 TEA buffer-acetonitrile-THF) | Acetonitrile |
| Gradient | See Table 2 | See Table 2 | Linear acetonitrile gradient (5 to 15%) over 4.0 min |
| Flow rate (ml/min) | 2.0 | 1.0 | 0.55 |
| Wavelength for detection (nm) | 280 | 280 | 230 |
| Injection vol (μl) | 20 | 20 | 5 |
| Criteria for impurities | For vancomycin B, NLT 80.0%; for any other impurity, NMT 9.0% | For each impurity, NMT 4.0%; total impurities, NMT 12.0%; disregard limit, area of vancomycin peak in lowest concentration solution | No criteriab |
a
Abbreviations: ODS, octadecylsilyl; TEA, triethylamine; THF, tetrahydrofuran; NLT, no less than; NMT, no more than.
b
The OTR-UPLC method is not associated with BP/USP monographs.