LC-MS法分析头孢硫脒降解产物

目的应用LC-MS技术快速鉴定头孢硫脒中的降解产物。方法根据头孢菌素的水解反应机制设计加速实验，确定头孢硫脒的2个主要降解产物为其水解产物；以1%冰醋酸溶液-乙腈(85∶15)为流动相，经C₁₈柱分离，通过电喷雾串联质谱，正离子检测，获得降解产物的相对分子质量信息和碎片信息，并辅助UV特征和色谱保留特征确定降解产物的结构。结果在所建立的条件下，头孢硫脒及其降解产物得到有效的分离，2个主要降解产物分别为去乙酰基头孢硫脒和头孢硫脒内酯。结论利用LC-MS技术可推测头孢菌素降解产物的结构，且本方法快速、灵敏、专属性高。

Identification of the degradation compounds of cefathiamidine by liquid chromatography-tandam mass spectrometry

AIM: To identify the degradation compounds of cefathiamidine by a liquid chromatography-tandam mass spectrometry (LC-MS). METHODS: According to the accelerated storage condition, two main degradation compounds of cefathiamindine were its hydrolytic products. Cefathiamidine was separated on a C18 column, with 1% acetate solution-acetonitrile (85 : 15) as mobile phase. The mass spectra and MS/MS spectra were obtained with set at the positive ion mode. Combined the UV spectra and the chromatography behavior, the structures of two degradation compounds were identified. RESULTS: The method can be used for the separation of the degradation compounds of cefathiamindine. The two major degradation compounds were desacetylcefathiamidine and cefathiamidine lactone. CONCLUSION: The method is rapid, sensitive and specific, and it is suitable for the identification of the degradation compounds of cephalosporin.