AUTOMATED MULTIPLE DEVELOPMENT THIN-LAYER CHROMATOGRAPHY OF SOME PLANT-EXTRACTS

The separation of ten plant extracts using automated multiple developm ent thin-layer chromatography (AMD-TLC) is described. Alcoholic extrac ts were obtained from Cinchona succirubra, Aesculus hippocastanum, Ber beris vulgaris, Artemisia abrotanum, Carduus marianus, Thuja occidenta lis, Baptisia tinctoria, Paulinia cupana, Lycopus europaeus and Echina cea augustifolia. The separation was performed on silica plates (Sil G -50 UV 254 (Macherey-Nagel), 10 x 20 cm). AMD was achieved in 25 steps using methanol, ethyl acetate, toluene, 1,2-dichloroethane, 25% ammon ia solution and anhydrous formic acid as modifiers. The chromatograms were evaluated with a Shimadzu CS-9000 dual-wavelength flying-spot sca nner. Better separations were obtained using AMD than isocratic elutio n.