A mass spectrometer compatible, reverse-phase high-performance liquid chromatography method capable to resolve twenty-six impurities and degradation products (DPs) in Ertapenem (ERT) has been developed. Eight dimer impurities (m/z 951) and two dehydrated dimers (m/z 933) were baseline resolved. Out of eight dimers, four dimers are reported the first time. The impurities and DPs were identified using LC–MS/MS. The chromatographic separation was achieved on X-Terra RP 18 (150 × 4.6 mm, 3.5 µm) column using gradient elution. The separation was dependent on the pH of the mobile phase, optimum separation was achieved using the mobile phase of pH 8. Mobile phase-A comprised of a mixture of ammonium formate buffer (pH 8.0), water and acetonitrile in a ratio of 40:60:01; v/v/v. Mobile phase-B comprised of a mixture of ammonium formate buffer (pH 8.0), acetonitrile and methanol in a ratio of 40:50:10; v/v/v. The flow rate was 1.0 mL min−1 and column was maintained at 40 °C. Considering the fragility of ERT and demand of faster analysis method, the method was further transformed on rapid resolution column with a run time of 10 min. The later method also produced the same kind of selectivity with enhanced sensitivity.

中文翻译：

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厄他培南杂质分布的高效 HPLC-MS 方法

已开发出一种与质谱仪兼容的反相高效液相色谱方法，能够解析厄他培南 (ERT) 中的 26 种杂质和降解产物 (DP)。八种二聚体杂质 (m/z 951) 和两种脱水二聚体 (m/z 933) 得到基线分离。在八个二聚体中，四个二聚体首次被报道。杂质和 DP 使用 LC-MS/MS 进行鉴定。使用梯度洗脱在 X-Terra RP 18（150 × 4.6 mm，3.5 µm）色谱柱上实现色谱分离。分离取决于流动相的 pH 值，使用 pH 值为 8 的流动相可实现最佳分离。流动相 A 由甲酸铵缓冲液 (pH 8.0)、水和乙腈的混合物组成，比例为 40： 60:01; v/v/v。流动相-B 由甲酸铵缓冲液 (pH 8.0) 的混合物组成，乙腈和甲醇的比例为40:50:10；v/v/v。流速为 1.0 mL min-1，色谱柱温度保持在 40 °C。考虑到 ERT 的脆弱性和对更快分析方法的需求，该方法在运行时间为 10 分钟的快速分离柱上进一步转换。后一种方法也产生了具有增强灵敏度的相同选择性。