关键词: font-size:medium, ">注射用盐酸头孢吡肟； 聚合物； 高效凝胶色谱法； 液质联用； 头孢类抗生素

Abstract: Objective： To infer the structures of the polymers in cefepime hydrochloride for injection by high performance gel chromatography coupled with mass spectrometry. Methods： TSK gel G2000SWxl column was used， with 5 mM ammonium formate solution-acetonitrile（95∶5) as the mobile phase， flow rate of 0.8 mL·min-1， detection wavelength of 254 nm， and column temperature of 25 ℃. Mass spectrometry data of various polymers was obtained in positive ion mode， and the structures of polymers were analyzed based on the mass spectrometry fragmentation rules and degradation reaction rules of cephalosporin polymers. Results： The chemical structures of four polymers were inferred. Two of them were dimers， and other two were trimers， which were reported for the first time. Conclusion： The chemical structures of the polymers in cefepime hydrochloride for injection can be quickly inferred using high performance gel chromatography combined with mass spectrometry technology， which can provide guidance for the isolation and identification of polymers in other cephalosporins and their quality improvement.

Key words: font-size:medium, ">Cefotaxime hydrochloride for injection； Polymers； High performance gel chromatography； Liquid chromatography-mass spectrometry； Cephalosporins