UV法和HPLC法测定北虫草中虫草素含量的方法比较

Comparison of UV and HPLC Methods for the Determination of the Content of Cordycepin in Cordyceps Militaris

目的:探讨UV法和HPLC法测定北虫草中虫草素含量的方法的可行性。方法:应用超声水提法获得北虫草提取液,UV法检测波长为260 nm,HPLC法采用ZOXBAX SB-C18色谱柱,水-甲醇(85∶15)为流动相,波长同UV法。结果:(1)紫外扫描和DAD三维图谱显示北虫草水提取液为混合物。(2)HPLC色谱图显示,在260 nm波长下不仅有虫草素峰,还有其他8个峰,提示有多种物质在这一波长下有吸收。(3)应用UV法测得的虫草素的含量是HPLC法的4～6倍。结论:北虫草水提取液为混合物,文献[11]介绍的UV法专属性差,不可直接用于该提取液中虫草素含量的测定,可选择专属性强的HPLC法。

Objective： To study the feasibility of UV and HPLC methods for the determination of the cordycepin content in Cordyceps militaris. Methods： Cordyecps militaris water extract was obtained by ultrasonic extraction,ZOXBAX SB-CI8 column was selected in HPLC. Water-methanol（85：15）was used as the mobile phase.The detection wavelength of 260 nm was used in UV and HPLC. Results： 1. The UV scan results and DAD 3D chromatogram showed that Cordyceps militaris water extract was a mixture.2. There were another eight peaks at 260 nm in the HPLC chromatogram,in addition to the cordycepin peak,indicating that many substances exist in above wavelength absorption. 3. The cordycepin content determinated by UV was 4-6 times than that did by HPLC. Conclusion： Cordyceps militaris water extract was a mixed solution. As the specificity of UV introduced by the article was poor, it could not be directly used to measure the content of cordycepin in the extract. And yet HPLC may be chosen owing to high specificity.