Department of Chemistry, Zhejiang University, Hangzhou 310027, China.
Talanta. 2010 Jan 15;80(3):1292-7. doi: 10.1016/j.talanta.2009.09.027.
The application of ionic liquids based microwave-assisted extraction (ILMAE) was successfully developed for extracting three alkaloids N-nornuciferine, O-nornuciferine, and nuciferine from lotus leaf. Seven kinds of 1-alkyl-3-methylimidazolium with different cations and anions were investigated in this work and 1.0M 1-hexyl-3-methylimidazolium bromide ([C(6)MIM]Br) solution was selected as solvent. In addition, the microwave parameters including irradiation power, extraction time and solid-liquid ratio were optimized. Compared with the regular MAE and conventional heat-reflux extraction (HRE), the proposed approach exhibited higher efficiency (0.9-43.7% enhanced) and shorter extraction time (from 2h to 2min), which indicated ILMAE was an efficient, rapid and simple sample preparation technique. Moreover, the proposed method was validated by the linearity, reproducibility, and recovery experiments. Good linearity was observed with the regression coefficients (r(2)) between 0.9998 and 0.9999. The recoveries of all methods were in the range of 94.6% and 105.5% with RSD lower than 6.6%, which indicated that the proposed method was credible.
基于离子液体的微波辅助萃取（ILMAE）在从荷叶中提取三种生物碱 N-去甲荷叶碱、O-去甲荷叶碱和荷叶碱方面得到了成功应用。本工作考察了 7 种不同阳离子和阴离子的 1-烷基-3-甲基咪唑盐，并选择 1.0M 1-己基-3-甲基咪唑溴盐([C(6)MIM]Br)溶液作为溶剂。此外，还优化了微波参数，包括辐射功率、提取时间和固液比。与常规 MAE 和常规热回流提取（HRE）相比，该方法具有更高的效率（提高了 0.9-43.7%）和更短的提取时间（从 2 小时缩短至 2 分钟），表明 ILMAE 是一种高效、快速、简单的样品制备技术。此外，还通过线性、重现性和回收率实验对该方法进行了验证。所有方法的线性度均良好，相关系数（r(2)）在 0.9998 至 0.9999 之间。所有方法的回收率均在 94.6%至 105.5%范围内，RSD 低于 6.6%，表明该方法可靠。
