title: A Comparative Study of Enantioseparations of Nα-Fmoc Proteinogenic Amino Acids on Quinine-Based Zwitterionic and Anion Exchanger-Type Chiral Stationary Phases under Hydro-Organic Liquid and Subcritical Fluid Chromatographic Conditions.
abstract: The focus of this contribution is a comparative investigation of enantioseparations of 19Nα-Fmoc proteinogenic amino acids onQuinine-based zwitterionic and anion-exchanger type chiral stationary phases employing hydro-organic and polar-ionic liquid and subcritical fluid chromatographic conditions. Effects of mobile phase composition (including additives, e.g., water, basis and acids) and nature of chiral selectors on the chromatographic performances were studied at different chromatographic modes. Thermodynamic parameters of the temperature dependent enantioseparation results were calculated in the temperature range 5-50 °C applying plots of lnα versus 1/T. The differences in standard enthalpy and standard entropy for a given pair of enantiomers were calculated and served as a basis for comparisons. Elution sequence in all cases was determined, where a general rule could be observed, both in liquid and subcritical fluid chromatographic mode the d-enantiomers eluted before the L ones. In both modes, the principles of ion exchange chromatography apply.
authors.affiliation: Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm tér 7, H-6720 Szeged, Hungary. gyula.lajko@pharm.u-szeged.hu.|Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary. gyula.lajko@pharm.u-szeged.hu.
authors.forename: Gyula
authors.initials: G
authors.lastname: Lajkó
authors.affiliation: Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm tér 7, H-6720 Szeged, Hungary. grecso.nora@pharm.u-szeged.hu.|Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary. grecso.nora@pharm.u-szeged.hu.
authors.forename: Nóra
authors.initials: N
authors.lastname: Grecsó
authors.affiliation: Institute of Medical Chemistry, University of Szeged, Dóm tér 8, H-6720 Szeged, Hungary. toth.gabor@med.u-szeged.hu.
authors.forename: Gábor
authors.initials: G
authors.lastname: Tóth
authors.affiliation: Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary. ferenc.fulop@pharm.u-szeged.hu.
authors.forename: Ferenc
authors.initials: F
authors.lastname: Fülöp
authors.affiliation: Department of Analytical Chemistry, University of Vienna, Währinger Strasse 38, 1090 Vienna, Austria. wolfgang.lindner@univie.ac.at.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Lindner
authors.affiliation: Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm tér 7, H-6720 Szeged, Hungary. apeter@chem.u-szeged.hu.
authors.forename: Antal
authors.initials: A
authors.lastname: Péter
authors.affiliation: Department of Inorganic and Analytical Chemistry, University of Szeged, Dóm tér 7, H-6720 Szeged, Hungary. ilisz@chem.u-szeged.hu.
authors.forename: István
authors.initials: I
authors.lastname: Ilisz
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D002852:Chromatography, Ion Exchange / Q000379:methods*; D005449:Fluorenes / Q000737:chemistry*; D015394:Molecular Structure; D011803:Quinine / Q000737:chemistry*; D012997:Solvents; D013237:Stereoisomerism; D013696:Temperature
chemical_list: D000596:Amino Acids; D005449:Fluorenes; C016456:N(alpha)-fluorenylmethyloxycarbonylamino acids; D012997:Solvents; D011803:Quinine
keywords: Nα-Fmoc-protected proteinogenic amino acids; enantiomer separation; hydro-organic liquid chromatography; subcritical fluid chromatography; temperature effect; weak anion-exchange chiral stationary phase; zwitterionic chiral stationary phase