Display Settings:


Send to:

Choose Destination
We are sorry, but NCBI web applications do not support your browser and may not function properly. More information
Talanta. 2007 Apr 30;72(2):587-93. doi: 10.1016/j.talanta.2006.11.027. Epub 2006 Dec 28.

Application of 1-alkyl-3-methylimidazolium-based ionic liquids as background electrolyte in capillary zone electrophoresis for the simultaneous determination of five anthraquinones in Rhubarb.

Author information

  • 1Department of Chemistry, Lanzhou University, Lanzhou, China; State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China.


A capillary zone electrophoresis method using only 1-alkyl-3-methylimidazolium-based ionic liquids as background electrolyte for the simultaneous determination of five anthraquinone derivatives including aloe-emodin, emodin, chrysophanol, physcion and rhein in Rhubarb species was described. Ion association constants, K(ass), between anthraquinone anions and imidazolium cations were determined by analyzing the electrophoretic mobility change of anthraquinone anions using a non-linear least-squares method and factors contributing to ion associability were systematically clarified. For method optimization, several parameters such as ionic liquids concentration, background electrolyte pH and applied voltage, on the separation were evaluated and the optimum conditions were obtained as follows: 90mM 1-butyl-3-methylimidazolium tetrafluoroborate (pH 11.0) with an applied voltage of 20kV. Under these conditions, the method has been successfully applied to the determination of anthraquinones in extracts of two kinds of Rhubarb plants (R. palmatum and R. hotaoense) within 12min. The method proposed herein was shown to be much simpler than the previously reported methods.

PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Write to the Help Desk