Chiral ligand-exchange CE assays for separation of amino acid enantiomers and determination of enzyme kinetic constant

✍ Scribed by Li Qi; Juan Qiao; Gengliang Yang; Yi Chen

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 275 KB
• Volume: 30
• Category: Article
• ISSN: 0173-0835
• DOI: 10.1002/elps.200800623

✦ Synopsis

Abstract

This paper deals with studies on the use of Zn(II)‐L‐ornithine complex as a chiral selecting system for the enantioseparation and UV detection of amino acids (AAs) by using the principle of ligand‐exchange CE. Successful enantioseparation of three pairs of label‐free aromatic AAs and four pairs of labeled AA enantiomers have been achieved with a buffer of 100.0 mM boric acid, 5.0 mM ammonium acetate, 3.0 mM ZnSO~4~ and 6.0 mM L‐Orn at pH 8.2. This new method was shown to be applicable to the quantitative analysis of D‐ and L‐aromatic AAs, with a linear range between 12.5 and 800.0 μg/mL, and a correlation coefficient above 0.99. Thus this assay, which is facile and relatively rapid, allows us to measure the enzyme catalytic activity in the incubation of D,L‐AAs with D‐AA oxidase. Using this new method, we can determine the enzyme kinetic constant, lending insight into potential enzyme mechanism.