毛细管气相色谱法测定中药蝉花中角鲨烯的含量

Determination of squalene in Cordyceps cicadae by capillary gas chromatography

目的：建立毛细管气相色谱法测定蝉花中角鲨烯的含量,确定蝉花中角鲨烯含量测定的最佳溶剂。方法：采用毛细管气相色谱法研究了8种不同提取溶剂对蝉花中角鲨烯含量的影响。色谱条件：HP-5毛细管色谱柱（柱长30 m,内径0.32mm,涂布厚度0.25μm,Agilent Technologies）;FID检测器,载气为N2,纯度99.999%,空气流速300 mL·min^-1,氢气流速30mL·min^-1,程序升温（初始温度180℃,以20℃·min^-1升温至210℃,保持3 min,然后以20℃·min^-1升温至250℃,保持5 min,最后以5℃·min^-1升温至280℃,保持5 min）;分流进样（10∶1）;进样口温度为280℃,检测口温度为290℃。结果：角鲨烯的检测浓度在42.90～171.6μg·mL^-1范围内线性关系良好（r=0.9999）,方法精密度良好（RSD=1.1%）,加标回收率为99.08%～100.7%,平均回收率（n=9）为99.70%。正己烷是蝉花中角鲨烯含量测定的最好溶剂,角鲨烯的含量为（74.36±0.24）μg·g^-1。结论：经方法学验证本方法可用于蝉花角鲨烯的含量测定。

Objective： To determine the content of squalene in Cordyceps cicadae and the optimum solvent for determination by capillary gas chromatography（ GC）. Methods： GC method was applied to determine the influence of 8different extraction solvents on the content of squalene. Chromatography conditions included the HP- 5 capillary column（ 250 mm × 0. 32 mm,0. 25 μm） with FID detector,the nitrogen carrier gas（ purity 99. 999%）,the air velocity of flow at 300 mL · min^-1,and the hydrogen at 30 mL·min^-1. The programmed temperature was started at180 ℃,then increased to 210 ℃ at a rate of 20 ℃ ·min^-1,and kept for 3 min,then increased to 250 ℃ at a rate of 20 ℃ ·min^-1,kept for 5 min,and finally increased to 280 ℃ at a rate of 5 ℃·min^-1 held for 5 min. The split injection was adopted with the split ratio 10∶ 1,the injector temperature at 280 ℃,and the detector temperature at290 ℃. Results： The results showed that a good linear relationship for the mass concentration of squalene from42. 90 μg·mL^-1 to 171. 6 μg·mL^-1 with the correlation coefficient of 0. 9999. The recovery rates of squalene in Cordyceps cicadae were 99. 08%- 100. 7%,and their average value（ n = 9） was 99. 70%. n- hexane was the best solvent for determination of squalene content in Cordyceps cicadae,by which,the content of squalene extracted with n- hexane was（ 74. 36 ± 0. 24） μg·g^-1 in Cordyceps cicadae. Conclusion： By the methodology the method is suitable for the determination of squalene in Cordyceps cicadae.