title: Direct chiral resolution of malic acid in apple juice by ligand-exchange capillary electrophoresis using copper(II)-L-tartaric acid as a chiral selector.
abstract: Chiral resolution of native DL-malic acid was achieved by ligand-exchange capillary electrophoresis using copper(II)-L-tartrate as a chiral selector. Factors affecting chiral resolution, migration time, and peak area of malic acid were studied. The running conditions for optimum separation of malic acid were found to be 1 mM copper(II) sulfate-1 mM L-tartrate (pH 5.1) with an effective voltage of -20 kV at 30 degrees C, using direct detection at 280 nm, and resolution (Rs) of racemic malic acid was approximately 4. With this system, D- and L-malic acids in apple juice were analyzed successfully.
authors.affiliation: Toyama Institute of Health, Japan. lee07664@nifty.ne.jp
authors.forename: S
authors.initials: S
authors.lastname: Kodama
authors.forename: A
authors.initials: A
authors.lastname: Yamamoto
authors.forename: A
authors.initials: A
authors.lastname: Matsunaga
authors.forename: T
authors.initials: T
authors.lastname: Soga
authors.forename: K
authors.initials: K
authors.lastname: Hayakawa
mesh_terms: D001628:Beverages / Q000032:analysis*; D003300:Copper / Q000737:chemistry; D019075:Electrophoresis, Capillary / Q000379:methods*; D005638:Fruit; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D008293:Malates / Q000032:analysis* / Q000737:chemistry; D013237:Stereoisomerism; D013644:Tartrates / Q000737:chemistry; D013696:Temperature
chemical_list: D007202:Indicators and Reagents; D008293:Malates; D013644:Tartrates; D003300:Copper; C030298:malic acid; C029768:tartaric acid