舒它西林的电喷雾-四极杆-飞行时间串联质谱裂解规律研究

为阐明药物舒它西林（氨苄西林/舒巴坦）的质谱裂解规律，采用电喷雾-四极杆-飞行时间串联质谱(ESI-Q-TOF-MS/MS)法在正离子模式下，对其离子碎片结构进行分析。通过质谱的高分辨能力及同位素氘代信息推断出舒它西林[M+H]⁺碎片离子断裂途径主要为氨苄西林部分的β-内酰胺环断裂，[M+Na]⁺裂解可观察到较多碎片离子峰，包括氨苄西林部分β-内酰胺环断裂、双酯连接处断裂和舒巴坦部分四元环断裂，此外有脱去CO₂、SO₂、CO等中性分子的峰出现。两种分析模式可为舒它西林的结构解析、体内代谢物质或环境中降解产物的研究提供快速鉴别理论依据。

Study on the Cleavage Rule of Sultamicillin by Electrospray Ionization-Quadrupole Time-of-Flight Mass Spectrometry

In order to clarify the fragmentation behaviors of Sultamicillin(ampicillin/sulbactam),Sultamicillin was investigated by the electrospray ionization-quadrupole-time of flight tandem(ESI-Q-TOF-MS/MS) mass spectrometry in positive ion mode.The fragmentation pathways were elucidated based on the high-resolution of mass spectrometer and isotope-labelling experiment.It was found that the protonated precursor ion + mainly fractured through β-lactam ring of Ampicillin.The + precursor ion provided more product ions fragmentation by the cleavage of β-lactam,diesters and four-member ring of Sulbactam part.In addition,the loss of neutral molecules such as CO2,SO2,CO was occurred readily.The fragmentation experiment of + and + precursor ions could provide theoretical knowledge for the rapid identification of structural analysis,metabolites in vivo and degradation products in the environment of Sultamicillin.