Separation of selected bile acids by TLC. III. Separation on various stationary phases

The aim of our study was to determine the optimum conditions of the separation of selected bile acids, such as cholic acid (C), glycocholic acid (GC), glycolithocholic acid (GLC), deoxycholic acid (DC), chenodeoxycholic acid (CDC), glycodeoxycholic acid (GDC), and lithocholic acid (LC) using thin-layer chromatography on aluminum plates which are precoated with silica gel 60 (E. Merck, #1.05553), silica gel 60F(254) (E. Merck, #1.05554), a mixture of silica gel 60 and Kieselguhr F-254 (E. Merck, #1.05567), as well as on glass plates which are precoated with silica gel 60F(254) (E. Merck, #1.05715) and on glass plates precoated with silica gel 60F254 with a concentrating zone (E. Merck, #1.11798) using n-hexane-ethyl acetate-acetic acid in various volume compositions as mobile phases. The retardation factor (R-f), and separation factors DeltaR(f) and R-s of each pair of examined bile acids were obtained. All bile acids have been successfully separated only on glass and aluminum plates precoated with silica gel by developing them with n-hexane-ethyl acetate-acetic acid in the following volume compositions: 20: 20: 5 and 22: 21 : 5 as the mobile phases.