title: Chiral separation and determination of amino acids in real samples by LE-MEKC using Cu(II)-L-proline as chiral selector.
abstract: This work reports that Cu(II) complexes with l-proline were used as chiral additives for the enantioseparations and determination of three underivatized amino acids by ligand-exchange micellar electrokinetic chromatography (LE-MEKC). Sodium dodecylsulfate (SDS) was shown to be necessary for simultaneous separation of the enantiomeric amino acids. Separation parameters such as SDS concentrations, the Cu(II)-l-proline ratio, the concentration of the copper(II) complex at a specific Cu(II)-l-proline ratio, pH and separation voltage were investigated for the enantioseparation in order to achieve the maximum possible resolution. A good separation was achieved in the BGE composing of 10mM ammonium acetate, 10mM Cu(II) and 20mM l-proline and 30 mM SDS at pH 5.0, and an applied voltage of 15 kV performed. Under above-mentioned optimum conditions, linearity was achieved within concentration ranges of up to two orders of magnitudes for the investigated amino acids with the correlation coefficients ranging from 0.9917 to 0.9984. The proposed method has been successfully applied to the determination of amino acid enantiomers in human urine, compound amino acids injection, and amino acid oral liquid.
authors: College of Pharmacy, Shanxi Medical University, Taiyuan 030001, China. Electronic address: wuyujiaoabc@163.com.
authors: Yujiao
authors: Y
authors: Wu
authors: College of Pharmacy, Shanxi Medical University, Taiyuan 030001, China.
authors: Yuyao
authors: Y
authors: Zhai
authors: College of Pharmacy, Shanxi Medical University, Taiyuan 030001, China.
authors: Yu
authors: Y
authors: Zhang
authors: College of Pharmacy, Shanxi Medical University, Taiyuan 030001, China.
authors: Hongfen
authors: H
authors: Zhang
authors: College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China. Electronic address: hwjing@lzu.edu.cn.
authors: Huanwang
authors: H
authors: Jing
authors: College of Pharmacy, Shanxi Medical University, Taiyuan 030001, China. Electronic address: chenanjia888@163.com.
authors: Anjia
authors: A
authors: Chen
mesh_terms: D000596:Amino Acids / Q000737:chemistry / Q000302:isolation & purification* / Q000652:urine*; D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods*; D003300:Copper / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D016014:Linear Models; D011392:Proline / Q000737:chemistry*; D015203:Reproducibility of Results; D013237:Stereoisomerism
chemical_list: D000596:Amino Acids; D003300:Copper; D011392:Proline
keywords: Amino acids; Chiral separation; LE-MEKC; Real samples