Abstract: A comprehensive two-dimensional liquid chromatographic separation system based on the combination of an immobilized liposome chromatographic (ILC) column and an ODS column was developed for the separation of components in Ginkgo biloba, a traditional Chinese medicine. Two columns were coupled by a two-position, eight-port valve equipped with two storage loops, and the system was controlled by a computer. The effluent was detected both by a diode array detector and by an atmospheric pressure chemical ionization (APCI) mass spectrometer. Under the optimization separation conditions with the separation system, more than 41 components in the methanol extract of Ginkgo biloba were resolved. According to their UV and mass spectra, 13 of them were preliminarily identified as ginkgolide B, ginkgolide C, bilobalide, rutin, quercetin, quercetin-3-O-β-D-glucosyl (1-2)-α-L-rhamnoside, quercetin-3-O-β-D-glucoside, isorhamnetin, kaempferol-3-O-β-D-glucosyl (1-2)-α-L-rhamnoside, isohamnetin-3-O-β-D-rutinoside, kaempferol-3-O-β-D-glucoside, kaempferol, kaempferol-3-O-β-D-rutinoside.

Key words: Ginkgo biloba extracts, mass spectrometry, traditional Chinese medicines , comprehensive two-dimensional liquid chromatography