title: Separation of enantiomers of chiral weak acids with polysaccharide-based chiral columns and aqueous-organic mobile phases in high-performance liquid chromatography: Typical reversed-phase behavior?
abstract: When polysaccharide-based chiral columns are used in combination with aqueous-organic mobile phases for the separation of enantiomers in high-performance liquid chromatography the separation mode is commonly called "reversed-phase" in analogy to achiral separations. In several earlier and recent studies on neutral and basic chiral analytes it was shown by our and other groups that due to multiple type of interactions involved in selector-selectand binding and enantioselective recognition with polysaccharide derivatives, the above mentioned separation system may not always behave like a reversed-phase system. In the present study additional examples of non-reversed-phase behavior are described for the first time for weak acidic chiral analytes. In addition, the reversal of enantiomer elution order was observed again for the first time for several analytes based on water-content in the mobile phase.
authors.affiliation: Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, 0179 Tbilisi, Georgia.
authors.forename: Iza
authors.initials: I
authors.lastname: Matarashvili
authors.affiliation: Faculty of Chemistry, Georgian Technical University, Kostava Str. 77, 0102 Tbilisi, Georgia.
authors.forename: Darejan
authors.initials: D
authors.lastname: Ghughunishvili
authors.affiliation: Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, 0179 Tbilisi, Georgia.
authors.forename: Lali
authors.initials: L
authors.lastname: Chankvetadze
authors.affiliation: Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, 0179 Tbilisi, Georgia.
authors.forename: Nino
authors.initials: N
authors.lastname: Takaishvili
authors.affiliation: Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, 0179 Tbilisi, Georgia.
authors.forename: Tamar
authors.initials: T
authors.lastname: Khatiashvili
authors.affiliation: Faculty of Chemistry, Georgian Technical University, Kostava Str. 77, 0102 Tbilisi, Georgia.
authors.forename: Maia
authors.initials: M
authors.lastname: Tsintsadze
authors.affiliation: Phenomenex Inc., 411 Madrid Ave., Torrance, 90501 CA, USA.
authors.forename: Tivadar
authors.initials: T
authors.lastname: Farkas
authors.affiliation: Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, 0179 Tbilisi, Georgia. Electronic address: jpba_bezhan@yahoo.com.
authors.forename: Bezhan
authors.initials: B
authors.lastname: Chankvetadze
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000143:Acids / Q000737:chemistry* / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D056148:Chromatography, Reverse-Phase; D006586:Hexanes / Q000737:chemistry; D000432:Methanol / Q000737:chemistry; D009930:Organic Chemicals / Q000737:chemistry*; D004364:Pharmaceutical Preparations / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000097:Acetonitriles; D000143:Acids; D006586:Hexanes; D009930:Organic Chemicals; D004364:Pharmaceutical Preparations; D011134:Polysaccharides; C026385:n-hexane; D000432:Methanol; C032159:acetonitrile
keywords: Chiral HPLC; Enantioseparations; Polysaccharide-based chiral stationary phases; Reversal of enantiomer elution order