Chiral separation of phenylalanine and  tryptophan by capillary electrophoresis using  a mixture of β-CD and chiral ionic liquid ([TBA]  [L-ASP]) as selectors.
In this paper, a simple, effective and green capillary electrophoresis separation and detection method was developed for the quantification of underivatized amino acids (dl-phenylalanine; dl-tryptophan) using β-Cyclodextrin and chiral ionic liquid ([TBA] [l-ASP]) as selectors. Separation parameters such as buffer concentrations, pH, β-CD and chiral ionic liquid concentrations and separation voltage were investigated for the enantioseparation in order to achieve the maximum possible resolution. A good separation was achieved in a background electrolyte composed of 15 mm sodium tetraborate, 5 mm β-CD and 4 mm chiral ionic liquid at pH 9.5, and an applied voltage of 10 kV. Under optimum conditions, linearity was achieved within concentration ranges from 0.08 to 10 µg/mL for the analytes with correlation coefficients from 0.9956 to 0.9998, and the analytes were separated in less than 6 min with efficiencies up to 970,000 plates/m. The proposed method was successfully applied to the determination of amino acid enantiomers in compound amino acids injections, such as 18AA-I, 18AA-II and 3AA.
Wu
W
Yujiao
Wang
W
Guoyan
Zhao
Z
Wenyan
Zhang
Z
Hongfen
Jing
J
Huanwang
Chen
C
Anjia
D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods*; D052578:Ionic Liquids / Q000737:chemistry; D010649:Phenylalanine / Q000737:chemistry* / Q000302:isolation & purification; D013237:Stereoisomerism; D014364:Tryptophan / Q000737:chemistry* / Q000302:isolation & purification; D047392:beta-Cyclodextrins / Q000737:chemistry
D052578:Ionic Liquids; D047392:beta-Cyclodextrins; D010649:Phenylalanine; D014364:Tryptophan; C031215:betadex