ANALYSIS OF TAXOL AND RELATED TAXANES FROM TAXUS-CANADENSIS USING LIQUID-CHROMATOGRAPHY COMBINED WITH MASS-SPECTROMETRY OR TANDEM MASS-SPECTROMETRY

A liquid chromatography/mass spectrometry (LC/MS) method using nebuliz er-assisted electrospray (ionspray) is described for the analysis of t axol and related taxane analogs in plant extracts from Taxus canadensi s. The method used a reverse-phase liquid chromatography gradient elut ion which was entirely compatible with the operation of ionspray ioniz ation. Abundant protonated molecules with limited fragmentation were o btained using this ionization technique, and provided adequate sensiti vity for monitoring taxol in crude resin extracts. The LC/MS method wa s evaluated for the analysis of taxol present at levels of 0.2% in res in extracts. Using selected-ion monitoring, the method provided detect ion limits of 50 ng/mL. In addition, other taxane analogs were identif ied in crude resin extracts using liquid chromatography combined with tandem mass spectrometry. Parent-ion scans for a fragment ion characte ristic of the taxane nucleus provided the necessary selectivity and se nsitivity for the identification of potentially active diterpenes in c omplex extracts.