夫西地酸有关物质的色谱-质谱结构鉴定

Structural identification of the related substances of fusidic acid by LC-MS

采用色谱-质谱联用技术鉴定夫西地酸的有关物质。采用Agilent Extend-C18色谱柱(150 mm×4.6 mm,3.5μm),以甲醇-乙腈-水-甲酸为流动相梯度洗脱,对夫西地酸有关物质进行分离;采用电喷雾正离子化-飞行时间质谱法(ESI-TOF/MS)测定各有关物质的相对分子质量和元素组成,三重四极杆串联质谱(ESI-MS/MS)测定子离子特征,解析鉴定有关物质的结构。在所建立的条件下,夫西地酸及其有关物质分离良好,检测并鉴定出19个主要有关物质,其中11个为欧洲药典规定的已知有关物质,8个为未知有关物质。色谱-质谱联用技术能有效地分离鉴定夫西地酸中的有关物质,为其存储条件和质量控制提供参考依据。

To identify the related substances of fusidic acid by LC-MS,separation was performed on an Agilent Extend-C18 column（ 150 mm × 4. 6 mm,3. 5 μm） by linear gradient elution with a mobile phase consisting of methanol,acetonitrile and formic acid. Electrospray positive ionization high resolution TOF/MS was used for the determination of the accurate mass and elemental composition of parent ions of the related substances; triple quadrupole tandem mass was employed for the mass spectra determination of the product. The structures of the related substances were then figured out through the elucidation of the fragment ions. Fusidic acid and its related substances were adequately separated under the established HPLC conditions. Nineteen major related substances of fusidic acid were detected and speculated by hyphenated techniques. Eleven of them were recorded in European Pharmacopoeia,while the others have not been previously reported. The established LC-MS method is effective for the separation and identification of the related substances of fusidic acid and the results are useful for its storage conditions and quality assurance.