Journal of Chromatography A

A systematic investigation of high-performance liquid chromatographic (HPLC) conditions employing 27 cardenolide glycosides of Convallaria majalis showed that LiChrosorb RP-2 possesses the best separation efficiency for the “polar” glycosides whereas LiChrosorb RP-8 can be used for analysis of the “less polar” fraction. For crude extracts from Convallaria majalis the best results were obtained by coupling of a LiChrosorb RP-2 precolumn and two analytical columns (LiChrosorb RP-2 and LiChrosorb RP-8) in series in combination with stepwise gradient elution with acetonitrile-water. A comparison of the new method with the paper chromatographic technique currently used showed that the HPLC method gives much more information about the composition of these complex mixtures of cardiac glycosides. It also offers great advantages for the quantitative determination of single cardenolides in Convallaria majalis L.