Authors:Monika Waksmundzka-Hajnos, Mieczyslaw Hajnos, Ryszard Świeboda, and Anna Hawrył
Experimental results for the wicking process in a solid thin porous layer by liquids of different polarity with defined surface free energy components and viscosity has been considered theoretically. The method was used for determination of the solid surface free energy of the adsorbents used in thin layer chromatography. Experiments were performed on commercial glass plates precoated with silica, CN-silica, diol-silica, NH
-silica, and silanized silica with
-alkanes, diiodomethane, water, and formamide as mobile phases. Surface free energy components determined for investigated adsorbents were used for characterization and comparison of their surface properties.
Authors:Tadeusz Dzido, Rafał Majewski, Beata Polak, Władysław Gołkiewicz, and Edward Soczewiński
A commercially available horizontal DS chamber has been applied to the planar electrochromatographic (PEC) separation of a dye mixture and of the enantiomers of dl-phenylalanine on non-polar stationary phases with ethanol-buffer or acetonitrile-buffer as mobile phases. The mobile phase was driven electroosmotically by applying a 50–250 V cm
field along a 10-cm RP18 TLC plate. Use of a counter-plate to the chromatographic plate enables elimination of problems associated with excessive delivery of mobile phase to the chromatographic adsorbent layer. Compared with conventional TLC separations the efficiency of electrochromatography was higher and the development time shorter.