Abstract
The retention behavior of phenolic compounds was carried out by use of diol precoated plates and non‐aqueous solutions (mixtures of dichloromethane and propan‐2‐ol, methanol and diisopropyl ether, methanol and ethyl acetate) and aqueous solutions (mixtures of methanol and water). The relationships of retention vs. concentration of eluent were presented as plots of R M vs. logarithm of concentration of a more polar component for non‐aqueous solutions and R M vs. concentration of methanol in aqueous solution. Optimal conditions of separation of investigated compounds were chosen on the basis of correlation plots R M non‐aqueous system vs. R M aqueous system. On the basis of correlation lines and statistical parameters, optimal two‐dimensional thin‐layer chromatography conditions were chosen and applied in the separation of investigated plant extracts (Herba bursae pastoris, Herba polygoni hydropiperis, Herba polygoni avicularis, and Flos verbasci).