MATRIX-ASSISTED-LASER-DESORPTION IONIZATI ON OF GINSENOSIDES/

Molecular weight of 8 ginsenosides and the component of total saponion s in American ginseng have been determined by matrix-assisted laser de sorption/ionization mass spectrometry (MALDI-MS). The average error of the molecular weight of each ginsenoside was found less than 0.05%. T he results demonstrate that MALDI-MS is a very simple and useful metho d to measure the molecular weight of some high polar, thermal unstable small molecules with high sensitivity and reproducibility.