2D-LC-IT-TOF/MS联用Cef-SEC法鉴定注射用头孢硫脒中高分子杂质

Determining the polymers in Cefathiamidine for injection by Cef-SEC two-dimensional UPLC-IT TOF MS method

目的:建立高效分子排阻色谱法(Cef-SEC)测定头孢硫脒中的聚合物,并用应用在线脱盐-高效液相色谱-离子阱-飞行时间质谱对其聚合物进行结构鉴定。方法:采用WT-Cef-SEC(7.8 mm×30.0 cm,5μm)色谱柱;流动相为5 mmol·L-1磷酸盐缓冲液-乙腈(95∶5);进样量为20μL;检测波长为254 nm;ESI电离源,正离子扫描;主成分自身对照法计算聚合物的含量。结果:在该条件下头孢硫脒峰与聚合物峰分离良好;通过2D-LC-IT-TOF/MS推测出聚合物1为头孢硫脒二聚体,聚合物2为去乙酰头孢硫脒氧化杂质聚合体。结论:本方法适用于注射用头孢硫脒高分子杂质的测定,同时为β-内酰胺类抗生素中聚合物的分离、分析及产品质量提高提供了依据。

Objective:To establish a high performance size exclusion chromatography(Cef-SEC)method for determining the polymer in cefathiamidine and its structure identification.Method:The analysis was carried out by using a WT-Cef-SEC chromatography column(7.8 mm×30.0 cm,5μm);The mobile phase was 95 volumes of 5 mmol·L-1 ammonium acetate and 5 volumes of acetonitrile;The detection wavelength was 254 nm;The injection volume was 20μL.The ion source was ESI ionization source,the scan pattern was positive and the content of polymers was determined by main component selfcompare without calibration factor.Results:The polymers were completely separated from cefathiamidine.Polymer 1 was conjectured to be the dimer of cefathiamidine by 2D-LC-IT-TOF/MS.Polymer 2 was conjectured to be the dimer of deacetyl cefathiamidine oxidation.Conclusion:The method has provided basis for the separation and analysis ofβ-lactams polymers,and it can be used to improve the quality of product.