目的 建立银杏叶中银杏内酯 A,B,C和白果内酯的定性定量分析方法。方法 银杏叶以 2 0 %乙醇超声提取 ,乙酸乙酯萃取 ,再经酸性氧化铝 -活性炭 -硅藻土混合柱层析 ,在 10 0℃以双 -三甲基硅烷三氟乙酰胺硅烷化 6 0min后 ,用 HP- 5 MS毛细管色谱柱 ,柱温从 180℃程序升温至 30 0℃。采用选择离子监测 (SIM)方式 ,以峰值最高的碎片离子作为监视离子进行定量分析。结果 银杏内酯 A,B,C和白果内酯的保留时间分别为 13.7,14.3,15 .3和 6 .8min,特征 (监视 )离子 (m/ z)分别为 5 37,6 2 5 ,713及 45 5 (2 99) ;平均回收率分别为 10 2 .0 %,99.4%,96 .0 %和 96 .3%,RSD分别为 0 .5 4%,2 .40 %,1.98%和 2 .43%。结论 本方法操作简便、重现性好、专属性强、准确可靠 ,可作为银杏萜内酯的定性定量分析方法。

Object To develop a capillary GC-MS analytical method for identification and deter-mination of ginkg olide A, B, C and bilobalide (GA, GB, GC and BB) in Ginkgo biloba L. leaves. Methods The leave samples were extracted in ultrasonic bath with ethanol-water (20∶ 80) . The extract was purifiedby liquid-liquid extraction with ethylacetate followed by solid-phase extraction on a column mixed with acid Al₂O₃ , active carbon and celite. The terpenes were trimethylsilylated by BSTFA (with 1% TMCS)for 60 min at 100 ℃ and determined by GC-MS with HP-5 MS capillary column in the selected-ionmonitoring mode. The intense fragmentions were chosen as monito ringions for quantitative analysis.Cholesterol was used as an internal standard. Column temperature gradient: initial temperature 180℃ ,maintained 1 min, and then increased a t 20℃ /min to 260℃ , and finally a t 2℃ /min up to 300℃ , maintained2 min. Results The retention times of GA, GB, GC and BB were 13. 7, 14. 3, 15. 3 and 6. 8 min,the major fragmentationions (monitoring) were at m/z 537, 625, 713 and 455 (299) , the average recoveriesof GA, GB, GC and BB were 102. 0% , 99. 4% , 96. 0% , 96. 3% , RSD were 0. 54% , 2. 40% , 1. 98%and 2. 43% , respectively. Conclusion This method is repeatable, specific, accurate and easy to operate.It is adoptable for quality and quantity analysis of terpene lactones from G. biloba leaves.

浙江省中医药管理局青年科研基金(1999年)资助项目;浙江省分析测试基金资助项目(00021)