Enantioseparation of o-phthaldiadehyde derivatized amino acids using beta-CD-modified micellar electrokinetic chromatography in the mixed aqueous-organic media

A method for the enantioseparation of amino acids derivatized with o-phthal diadehyde (OPA) and N-acylated cysteine (AC) using beta -cyclodextrin (beta -CD)-modified micellar electrokinetic chromatography (MEKC) in the presenc e of organic modifier was developed. The effects of separation parameters, such as the pH Value of the buffer, the concentration of the buffer, beta - CD bile salt and organic modifiers, on the migration times and resolutions of chiral amino acids were investigated and the optimum experimental condit ions were 40 mmol l(-1) borax (pH 9.0), 60 mmol l(-1) sodium taurocholate ( STC), 30 mmol l(-1) beta -CD and 15% (v/v) of isopropanol (IPA). Using the proposed method, 11 pairs of OPA/AC-DL-amino acids were separated simultane ously with the resolution ranging from 1.038 to 3.367 in less than 19 min. (C) 2001 Elsevier Science B.V. All rights reserved.