Correlation of Migration Distance of Peptides in High-Performance Thin-Layer Chromatography and Pressurized Planar Electrochromatography Systems

Abstract

In a series of our previous papers we have investigated the influence of various variables on retention/migration of peptides in various high-performance thin-layer chromatography (HPTLC) and pressurized planar electrochromatography (PPEC) systems. Here we present a correlation of the selectivity of peptide separation in similar, as well as in various HPTLC and PPEC systems investigated before. Our results show that the selectivity in similar HPTLC and PPEC systems is quite different. This results from the share of electrophoresis in separation of solutes by PPEC. The results suggest that combination of HPTLC and PPEC, with properly selected separation conditions (the same, or even better-different for each technique), may be used for efficient two-dimensional separation of peptides. The best separation can be obtained if PPEC is carried out in two opposite directions (toward the cathode and the anode) simultaneously.

High Performance (High Pressure) Layer Electrochromatography Separation Technique: Equipment and Preliminary Results

“…The quite serious problem is that an attempt to avoid tailing of solute zones (e.g., by lowering pH of the mobile phase, addition of salts, buffers, ion-pairing reagents) very often leads to the reduction of EOF. 23 It is worth mentioning that commercially available chromatographic plates with a silica-based nonpolar adsorbent layer provide extensive interactions of solutes with free silanols, 24 , 25 contrary to HPLC adsorbents, which are designed to minimize such interactions. This only aggravates the problem.…”

“…As the mobile phase composition influences EOF, retention, and electrophoretic mobility of solutes at the same time, it is rather hard to optimize it to obtain satisfying results of separation of complex mixtures. The quite serious problem is that an attempt to avoid tailing of solute zones (e.g., by lowering pH of the mobile phase, addition of salts, buffers, ion-pairing reagents) very often leads to the reduction of EOF . It is worth mentioning that commercially available chromatographic plates with a silica-based nonpolar adsorbent layer provide extensive interactions of solutes with free silanols, , contrary to HPLC adsorbents, which are designed to minimize such interactions.…”