Enantioseparations of amino acids by capillary array electrophoresis with 532 nm laser induced fluorescence detection

• Separation of amino acid enantiomers by a 532 nm CAE-LIF scanner is presented.
• CDs were studied and β-CD was effective for these enantiomers.
• Additives were investigated and diamine was helpful for these enantiomers.
• Optimum is 100 mM Tris–borate buffer (pH 10), 2 mM β-CD and 10 mM hexamethylenediamine.
• Determination of the enantiomeric excess of nonracemic alanine is demonstrated.

Capillary array electrophoresis (CAE) is a promising technique for multiple enantiomeric separations. Carboxytetramethylrhodamine succinimidyl ester (TAMRA SE), a rhodamine-core fluorescent probe, has rarely been applied as an original precolumn derivatization reagent for chiral amino acid (AA) analysis so far. For these purposes, high-throughput enantiomeric separations of 12 TAMRA SE-AAs by a home-made 532 nm CAE-LIF scanner are presented. The effect of cyclodextrins (CDs) and a variety of organic modifiers was quickly investigated. Baseline separations were achieved in 100 mM Tris–borate buffer (pH 10.0) containing 2 mM β-CD and 10 mM hexamethylenediamine (HDA). Multiple determination of the enantiomeric excess (ee) in non-racemic mixtures of alanine is successfully presented.