拉曼光谱定性和定量检测青蒿素研究

青蒿素是从中药青蒿中提取的含有过氧基团的倍半萜内酯药物,具有良好的抗疟特性,是治疗疟疾的特效药。运用激光拉曼光谱分析了100~3 500 cm~(-1)光谱范围内青蒿素的声子振动特性。指出位于724cm~(-1)的拉曼峰为与青蒿素中过氧基团直接相关的一个特性声子振动模式,可用于检测过氧桥键的存在。位于1 734 cm~(-1)的拉曼峰为与青蒿素中内酯基团直接相关的一个特性声子振动模式,可用于进一步检测分析青蒿素。由于这两个特征拉曼峰对应于青蒿素分子中特征化学键的振动,而且在实验上较容易观察分析,因而它们可以很好的用于拉曼光谱法快速初步定性检测青蒿素。同时,通过分析比较不同纯度青蒿素样品中724和1 734 cm~(-1)处特征拉曼峰的平均散射信号强度比,拉曼光谱法可以用于定量检测青蒿素样品的纯度。与常用的高效液相色谱法相比,拉曼光谱法更快速方便,检测精度更高,而且可以检测青蒿素样品纯度的均匀性。拉曼光谱法定性和定量检测青蒿素纯度的功能对分析检测中药青蒿的品质也有重要意义。

Qualitative and Quantitative Studies on Artemisinin with Raman Spectroscopy

Artemisinin,one of the most powerful new generation antimalarial drugs,is an unique sesquiterpene lactone compound extracted from traditional Chinese drug Artemisa annua L,which contains specific endoperoxide bridge .In this study,the Raman scattering of artemisinin in the spectral range of 100～3 500 cm-1 has been investigated .The analysis suggests that the phonon mode at 724 cm-1 would be directly correlated with a representative vibrational mode of the ring containing endoperoxide bridge,thus it can be applied for Raman detection of endoperoxide bridge in artemisinin .The phonon mode at 1 734 cm-1 would be directly correlated with a representative vibrational mode of the lact one ring,thus can be applied for further identification of artemisinin with Raman spectroscopy .Also both of these two phonon modes can be easily observed by Raman experiment; therefore they are good representative phonon modes for quick qualitative analysis of artemisinin by Raman spectroscopy .In addition,by investigating the relative intensity ratio of the two representative phonon modes a t 724 and 1 734 cm-1,the Raman method can be applied for quantitative analysis of artemisinin purity .Compared with the commonly used high performance liquid chromatography method,the Raman method is much more powerful: it is f aster,more convenient,more accurate,and can be applied for the analysis of homogeneity of purity for artemisinin samples .Furthermore,the qualitative and quantitative analysis of artemisinin purity would be very helpful for quantitative analysis of the quality of Chinese drug Artemisa annua L with Raman spectros copy .