DISPLACEMENT THIN-LAYER CHROMATOGRAPHY OF SOME ECDYSTEROIDS

The essential steps of displacement thin-layer chromatography and its applications for separation of ecdysteroids are outlined. Finding adeq uate conditions of displacement thin-layer chromatography for plant ec dysteroids is detailed including the optimisation of mobile phase comp osition, mobile phase flow rate, and preelution before displacement de velopment. Application of preelution before displacement chromatograph y has an importance in the case of planar chromatography, both explori ng and achieving the displacement separations by HPLC.