“…10 High-performance liquid chromatography (HPLC) for determination of five free anthraquinones is frequently used for quality control of Radix et Rhizoma Rhei according to the Chinese Pharmacopoeia and related literatures. 1,9,[11][12][13][14][15][16][17][18][19] Moreover, thin-layer chromatography (TLC), 20,21 capillary electrophoresis (CE), 22,23 ultra-performance liquid chromatography (UPLC), 6,24 UPLC-mass spectrometry (MS), 3 and high speed counter current chromatography (HSCCC) 25 also have been reported for determination of the main bioactive components in Radix et Rhizoma Rhei. However, all the analytical methods above for determining and quantifying Radix et Rhizoma Rhei suffer from the intrinsic limitations of chromatography-based methods, namely, the need of standard compounds for analyte identification or quantification and the relatively long analysis times.…”