电喷雾离子化多级质谱对雷帕霉素及其类似物特征性碎片的分析

目的: 建立一种快速鉴别雷帕霉素及其类似物的方法。 方法: 采用电喷雾离子化源(ESI源);极性检出模式为负模式(MS^-),毛细管电压4 kV;干燥气(N₂)流速5.98 L·min^-1;干燥气温度300 ℃;雾化气压力137.93 kPa。 结果: 对雷帕霉素及其类似物的裂解途径进行分析归纳,在电喷雾离子化多级质谱条件下,它们的开环裂解主要发生在C²⁷-C²⁸,产生相应的特征碎片离子峰。 结论: 本法简便、灵敏,可应用于雷帕霉素及类似物的快速鉴别。

Objective: To develop a rapidaly method for the identification of rapamycin and its analoges. Methods: Electrospray ionization mass spectrometric method in negative mode was applied.Analysis was performed at the flow rate of dry gas 5.98 L·min^-1 with the temperature at 300 ℃ and the pressure of nebulizing gas 137.93 kPa.The capillary voltage was set at 4 kV. Results: The fragmentation patterns and structural assignments of these substances were discussed.Under the experimental conditions,the main fragmentation pathways started by primary splitting between C²⁷-C²⁸.Some specific fragment ions were appeared in the mass spectra. Conclusion: The method with simplicity and specificity and sensitivity has been established for the rapidly identification of rapamycin and its analoges.