title: Chiral ligand-exchange separation and determination of malic acid enantiomers in apple juice by open-tubular capillary electrochromatography.
abstract: This study describes the application of an open tubular capillary column for chiral ligand-exchange separation and determination of malic acid enantiomers in apple juice by open-tubular capillary electrochromatography (OT-CEC). The open tubular column was prepared by in-situ grafting polymerization of 3-chloro-2-hydroxypropyl methacrylate (HPMA-Cl) and followed by L-Histidine (L-His) modification. L-His was used as a chiral ligand-exchange selector and copper (II) as a central ion. The electrochromatographic characterization of the open tubular column was performed with the use of thiourea as an electroosmotic flow (EOF) marker. Factors affecting electrochromatographic enantioseparation of malic acid were also studied. The running buffer conditions for optimum enantioseparation of malic acid were found to be ACN/5.0mM CuSO4, 20.0mM (NH4)2SO4 (60/40%, v/v) adjusted to pH 3.0. The separation and determination of the enantiomers of malic acid in the apple juice solution diluted 10- to 40-folds were successfully achieved.
authors.affiliation: Department of Food Engineering, Bingöl University, Bingöl, Turkey. Electronic address: aydoganc@hacettepe.edu.tr.
authors.forename: Cemil
authors.initials: C
authors.lastname: Aydoğan
authors.affiliation: Department of Chemistry, Biochemistry Division, Hacettepe University, Ankara, Turkey.
authors.forename: Veyis
authors.initials: V
authors.lastname: Karakoç
authors.affiliation: Department of Chemistry, Biochemistry Division, Hacettepe University, Ankara, Turkey.
authors.forename: Adil
authors.initials: A
authors.lastname: Denizli
mesh_terms: D053801:Capillary Electrochromatography / Q000379:methods*; D000067030:Fruit and Vegetable Juices / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D008024:Ligands; D008293:Malates / Q000737:chemistry*; D027845:Malus / Q000737:chemistry*; D008689:Methacrylates / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D008024:Ligands; D008293:Malates; D008689:Methacrylates; C030298:malic acid
keywords: Apple juice; Chiral separation; Cosmetics; Food analysis; Ligand-exchange; Malic acid; Open-tubular capillary electrochromatography