Enantioseparation of a-substituted proline analogs with macrocyclic glycopeptide-based chiral stationary phases immobilized on superficially porous particles of silica applying liquid chromatography with ultraviolet and mass spectrometric detection

• DOI: 10.1016/j.chroma.2023.463997
• Publication Date: 2023-04-14T23:39:36Z
• Authors: Dániel Tanács; Róbert Berkecz; Daniel W. Armstrong; Antal Péter; István Ilisz
• Keywords: Teicoplanin; Van Deemter equation

In this study, the liquid chromatography-based direct enantioseparation of stereoisomers α-substituted proline analogs has been investigated utilizing chiral stationary phases with UV and/or mass spectrometric (MS) detection. Macrocyclic antibiotics, such as vancomycin, teicoplanin, modified and teicoplanin aglycone, all covalently immobilized to 2.7 μm superficially porous silica particles have applied phases. Mobile mixtures methanol acetonitrile different additives (polar-ionic mode) were optimized during method development. Best separations achieved mobile 100% MeOH containing either 20 mM acetic acid or triethylammonium acetate. Special attention was given applicability MS-compatible Acetic found be advantageous a phase additive for MS Enantioselective chromatographic behaviors are interpreted based on explored correlations between analytes' structural features those For thermodynamic characterization, studied in temperature range 5-50 °C. Generally, retention selectivity decreased increasing temperature, most cases, enthalpy-driven enantiorecognition observed, but entropic contributions also present. Unexpectedly, unusual shapes van Deemter curves registered kinetic evaluations. General trends could observed enantiomeric elution orders: S < R VancoShell NicoShell, opposite TeicoShell TagShell columns.