The determination of some amino acids by conventional and hot plate chromatography

Thin-layer chromatography of DNS amino acids derivatives in systems with silica gel and silanized silica gel plates

Investigations into separation selectivity of High-Performance Thin-layer chromatography (HPTLC) of dansyl (DNS) derivatives of amino acids in silica gel (Silica gel 60 F254s plates) and silanized silica gel (RP-18 W plates) systems are presented. The results have been obtained for mobile phases containing different concentrations of acetonitrile (ACN) in formic acid (FA) water solution (final concentration of FA in the mobile phase was equal to 265 mmol/dm3). The data obtained show differences in separation selectivity of the solutes between employment of HPTLC silica gel and RP-18 W systems.

Pressurized planar electrochromatography of DNS amino acids derivatives in silica gel and silanized silica gel systems with formic acid addition to the water mobile phase

Pressurized planar electrochromatography (PPEC) of dansyl (DNS) derivatives of amino acids in normal- and reversed-phase systems is presented. The results have been obtained for mobile phases with different acetonitrile (ACN) concentrations (0–85%). The data obtained show differences in separation selectivity between high-performance thin-layer chromatography (HPTLC) and PPEC systems. These differences originate from the electrophoretic effect which is involved in the PPEC system, contrary to the HPTLC one.