Abstract: The ionic liquid dispersive liquid phase microextraction(ILDLPME) was developed and its mechanism was investigated; ILDLPME coupled with high performance liquid chromatography(HPLC) was introduced for the determination and evaluation of five kinds of low abundance phenylpropionic acid compounds of Rhizoma typhonii from different origins. The main parameters affecting the performance of ILDLPME were optimized. Under the optimized parameters, the linear ranges were 1.28×10^-3-2.60 μg/mL for caffeic acid, 1.28×10^-4-2.60 μg/mL for p-hydroxycinnamic acid and ferulic acid, 1.28×10^-3-4.00 μg/mL for cinnamic acid and p-methoxycinnamic acid, respectively; the limits of detection were 0.13, 0.01, 0.01, 0.13 and 0.13 ng/mL, respectively; the intra and inter RSD were less than 9.7%, the mean recoveries of analytes in traditional Chinese medicines were between 86.9% and 112.6%, the enrichment factors were in the range of 56.0-159.3 for ILDLPME. By analysis and comparison the UV spectra of phenylpropionic acids before and after ILDLPME, the extraction mechanism of the charge transfer superamolecule of carboxyl-ionic liquid(CTSMCIL) was proposed. CTSMCIL-HPLC provide dependably theoretic foundation and experimental evidence for establishing quality control method in Rhizoma typhonii.

Key words: Ionic liquid dispersive liquid phase microextraction(ILDLPME), Charge transfer superamolecule of ionic liquid(CTSMCIL), Enrichment factor, Rhizoma typhonii, Phenylpropionic acid compounds