Isolation of milligram quantities of sanguinarine and chelerithrine from the roots of Chelidonium majus L. by zonal micropreparative TLC

By use of pH 6.0 acetate buffer a mixture of Chelidonium majus L, alkaloids has been separated, on a classical silica column, into two groups, tertiar y and quaternary alkaloids, The relationships between R-F and the concentra tion of methanol in the acetate buffer suggested it was possible, by gradie nt elution in which the concentration of methanol in the pH 6.0 aqueous ace tate buffer was increased, to separate the quaternary alkaloids further int o fractions containing 2 or 3 alkaloids, These fractions were then separate d by micropreparative zonal thin-layer chromatography Sanguinarine and chel erithrine of high purity were obtained.