Direct chiral resolution of malic acid in apple juice by ligand-exchange capillary electrophoresis using copper(II)-L-tartaric acid as a chiral selector

Electrophoresis. 2001 Sep;22(15):3286-90. doi: 10.1002/1522-2683(200109)22:15<3286::AID-ELPS3286>3.0.CO;2-J.

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.

MeSH terms

  • Beverages / analysis*
  • Copper* / chemistry
  • Electrophoresis, Capillary / methods*
  • Fruit*
  • Hydrogen-Ion Concentration
  • Indicators and Reagents
  • Malates / analysis*
  • Malates / chemistry
  • Stereoisomerism
  • Tartrates* / chemistry
  • Temperature

Substances

  • Indicators and Reagents
  • Malates
  • Tartrates
  • Copper
  • malic acid
  • tartaric acid