青蒿素与氢氧化钠反应的动态紫外吸收光谱

Transient UV Absorption Spectra of Artemisinin Reacting with Sodium Hydroxide

采用ICCD动态光谱测量系统，准确地拍摄出了青蒿素自身的紫外吸收光谱，并对不同浓度的青蒿素与氢氧化钠反应的全过程进行了动态光谱实时测量，每幅光谱的曝光时间为0．1ms。实验结果显示，青蒿素自身有一明显的紫外吸收带，吸收峰值为212．52nm青蒿素极易与氢氧化钠反应，不同浓度的青蒿素与氢氧化钠反应的吸收光谱变化情况是相似的，只是变化发生的时刻有所不同。反应初首先出现一以288nm为峰值的新吸收带，随着反应的进行，在260nm处的吸收逐渐增强，反应的最终产物在200-350nm之间形成一稳定连续的强吸收带。此反应过程的动态光谱信息在国内外还未见有报道。其结果为了解青蒿素这一潜在抗癌药物与碱性物质反应的特性提供了实验依据，对正确使用青蒿素具有参考价值。

UV absorption spectrum of artemisinin and transient absorption spectra of various concentrations of artemisinin reacting with sodium hydroxide were measured by using an intensified spectroscopic detector ICCD. The exposure time of each spectrum was 0.1 ms. Results indicate that artemisinin has an obvious UV absorption band centered at 212.52 nm and can react with sodium hydroxide easily. All absorption spectra of different concentrations of artemisinin reacting with sodium hydroxide have the similar changes, but the moment at which the changes happened is different. After adding sodium hydroxide into artemisinin in ethanol solution, there was a new absorption band centered at 288 nm appearing firstly. As reaction went on, the intensity of another absorption band centered at 260 nm increased gradually. At the end of the reaction, a continuous absorption band from 200 to 350 ran with the peak at 245 nm formed finally. No other transient absorption spectral data are available on the reaction of artemisinin with sodium hydroxide currently. The new spectral information obtained in this experiment provides very important experimental basis for understanding the properties of artemisinin reacting with alkaline medium and is useful for correctly using of artemisinin as a potential anticancer drug.