Quantitative determination of ginsenosides by high-performance liquid chromatography-tandem mass spectrometry.

An HPLC-MS/MS method was developed for the quantitative determination of ginsenosides, which are the marker compounds for herbal products containing Panax ginseng (Korean or Chinese ginseng) and P. quinquefolius (American ginseng). Samples were extracted with BondElut C18 HF extraction columns and the concentrations of seven major ginsenosides (Rb1, Rb2, Rc, Rd, Re, Rf, and Rg1) were determined by reversed-phase HPLC-MS/MS employing a quadrupole-ion trap mass spectrometer. Both positive and negative electrospray ionisation techniques were evaluated. Positive ionisation spectra of these compounds gave strong sodium adduct molecular and sodium adduct dimer ions. Negative ionisation yielded the molecular ion primarily and was, therefore, used for analysis: quantitative determination was based on the most abundant product ions for each ginsenoside. The method was used to extract and analyse commercial samples of P. ginseng and P. quinquefolius.