▎ 摘　　要

Ginseng saponin Rg(3) has attracted much attention in the past decades due to its excellent antitumor activity. Rg(3) and related ginsenosides, as natural materials, have the potential to be the base and supporting materials for anticancer drugs. In the present study, infrared spectrum, mass spectrum, H-1 nuclear magnetic resonance spectrum, C-13 nuclear magnetic resonance spectra H-1-H-1 COSY, heteronuclear multiple-quantum coherence (HMQC) of loteprednol etabonate were applied and the results were interpreted. All the H-1 NMR and C-13 NMR chemical shifts were assigned by means of H-1-H-1 COSY\HMBC and HMQC. The molecular structure of ginsenoside Rg(3) has been elucidated. By using silver nanoparticles decorated graphene, the sensitive detection of Rg(3) was realized with electrochemical measurements. Electrochemical response was obtained in a wide range of concentration of ginseng saponin Rg(3) (0.2-1.4 mu mol/L) with the detection limit of 0.02 mu mol/L.