Simultaneous determination of notoginsenoside R1 and ginsenosides Rg1, Re, Rb1 in dietary supplements by HPLC-DAD

Abstract

A method using solid phase extraction (SPE) and high performance liquid chromatography with diode array detector (HPLC-DAD) has been optimized for the simultaneous determination of notoginsenoside R1 and three ginsenosides Rg1, Re, Rb1 in solid, oil, and liquid dietary supplements. The substances were separated by an InertSustain C18 column (250 mm × 4.6 mm i.d.; particle size 5 μm) with a gradient program composed of acetonitrile and water. Linearities were in the range of 4.0 - 400 μg/mL with the coefficients of determination were more than 0.999. The limits of detection and limits of quantitation were 2.13 - 6.89 μg/g and 7.11 - 22.98 μg/g, respectively. The recovery values of the compounds were in the range of 87.2 - 103.5%. The precision study showed the intra-day relative standard deviation (RSD) of 1.41 - 2.91%, and inter-day RSD of 1.87 - 4.85%, which meet the AOAC International requirements. The method was applied to determine the content of notoginsenoside R1, ginsenoside Rg1, ginsenoside Re, and ginsenoside Rb1 in 20 dietary supplement samples containing Ginseng and Pseudoginseng.