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Abstract: A simple, reproducible and sensitive micellar electrokinetic chromatography (MEKC) method was developed for the separation and determination of 10 saponins from Panax notoginseng. Field-enhanced sample injection with reverse migrating micelles (FESI–RMM) was used for on-line concentration of the saponins. The effects of concentrations of sodium dodecyl sulfate (SDS) and organic modifier, the sample matrix, the injection time of water plug, the injection voltage and injection time of sample on the separation and stacking efficiency were investigated. The optimum buffer contained 10mM H3PO4, 140mM SDS, 20% acetonitrile and 15% 2-propanol and the pH of buffer was 2.4. The sample solution was diluted with 15mM SDS and injected for 15s with −8kV after injection of 2s water plug. Under the optimum conditions, the analytes were well separated with very high plate number (8.0×105–1.2×106 N/m); the limits of detection of the analytes were 1.7–6.3μg/mL. The high sensitivity permitted the determination of two minor saponins Rh1 (1.01mg/g) and Rg2 (0.62mg/g) in P. notoginseng, which were not determined in the literature. [Copyright &y& Elsevier]

The Chinese phytomedicinal formulation Sanqi Zongdai Pian, traditionally prepared from crude extracts from roots of Panax notoginseng (Araliaceae), contains highly polar dammarane saponins which were separated at a preparative scale using high-speed counter-current chromatography (HSCCC). In each operation, 283 mg methanolic extract of five tablets was separated and yielded pure 157, 17, 13 and 56 mg of ginsenoside-Rb1, notoginsenoside-R1, ginsenoside-Re and ginsenoside-Rg1, respectively, n-hexane–n-butanol–water (3:4:7, v/v/v) was used for the two-phase solvent system of the HSCCC separation. The chemical structures of three ginsenosides and one notoginsenoside were elaborated by means of electrospray ionization MS–MS and NMR analysis. [Copyright &y& Elsevier]