Separations of amino acid enantiomers

Erank H, G. J. Nicholson and E. Bayer, Rapid gas cliromatographic separation of amino acid enantiomers with a novel cliiral stationary phase , J. Chromatogr. Sci. 15 174-176(1977). 

Separation of Amino Acid Enantiomers after Derivatization with Or/ho-Phthaldialdehyde (OPA) and a Unichiral Tliiol Compound... 

S Einarsson, B Josefsson, P Moller, D Sanchez. Separation of amino acid enantiomers and chiral amines using precolumn derivatization with (+)-l-(9-fluorenyl)ethyl chlo-roformate and reversed phase liquid chromatography. Anal Chem 59, 1191, 1987. 

Ilisz, I., Berkecz, R., and Peter, A., HPLC separation of amino acid enantiomers and small peptides on macrocyclic antibiotic-based chiral stationary phases a review, J. Sep. ScL, 29, 1305, 2006. 

CSPs and chiral mobile phase additives have also been used in the separation of amino acid enantiomers. Another technique that should be mentioned is an analysis system employing column-switching. D-and L- amino acids are first isolated as the racemic mixture by reverse-phase HPLC. The isolated fractions are introduced to a second column (a CSP or a mobile phase containing a chiral selector) for separation of enantiomers. Long et al. (2001) applied this technique to the determination of D- and L-Asp in cell culture medium, within cells and in rat blood. 

Naobumi, O. and Hajimu, K., HPLC separation of amino acid enantiomers on urea derivatives of L-valine bonded to silica gel, J. Chromatogr., 285, 198, 1984. 

Analytical Properties Separation of amino acid enantiomers most effective of the L-valine urea derivatives depends on hydrogen bond interactions usually prepared on LiChro-sorb (10 pm) hexane plus isopropanol modifier has been used as the liquid phase Reference 4... 

Enantioselective metal chelation is a technique that has been applied to the separation of amino acid enantiomers. In the method, a transition metal-amino acid complex, such as copper(II)-aspartame, in which the full coordination of the complex has not been reached, is added to the buffer. The amino acid enantiomers are able to form ternary diastereomeric complexes with the metal-amino acid additive if there are differences in stability between the two complexes, enantioselective recognition can be achieved. 

The observation of enantioselective binding properties of polysaccharides dates back to the early SOs. At this time Kotake [95] and Dalgliesh [96] achieved thin layer chromatographic separation of amino acid enantiomers on cellulose carriers. However, the poor chiral recognition capacity of native polysaccharides hampered further developments. 

In 1960, a patent was granted for the separation of D,L-prollne on a lactose column (56). Davankov s laboratory was the first to report separation of amino acid Isomers on polymeric resins derlvatlzed with optically active amino acids (57). However, separation of amino acid enantiomers by these techniques has been hampered by long separation times (ca. 10 hr) and the difficulty In synthesizing supports of sufficient quality for modern HPLC (spherical particles, small size, uniform chemical modification). Separation of amino acid Isomers on a column consisting of silica bonded with L-amlno acids and complexed with copper (II) has been reported by Gubltz and Jellenz (42). Short analysis times for separation of mixtures of single D,L-amlno acids were reported (ca. 30 min), but complex mixtures have not been separated. 

H. Bruckner and M. Wachsmann, Design of chiral monochloro-S-trizine reagents for the liquid chromatographic separation of amino acid enantiomers,/. Chromatogr. A., 2003, 998, 73-82. 

Lin, J.M. Nakagama, T. Uchiyama, K. Hobo, T. Capillary electrochromatographic separation of amino acid enantiomers using on-column prepared molecularly imprinted polymer. J. Pharmaceut. Biomed. Anal. 1997,15, 1351-1358. 

Existing separations of amino acid enantiomers, using commercially available stationary phases such as L-valine / r/-butylamide bound to polydimethylsiloxane (Chirasil-Val Figure 1) (7d), L-valine-5-l-(a-phenylethyl) amide bound to... 

Disz I, Berkeez R, Peter A. Application of chiral derivatizing agents in the high-performance liquid chromatographic separation of amino acid enantiomers a review. J Pharm Biomed Anal 2007 47 1—15. 

Most amino acids have a chiral center at the alpha position, resulting in L- and D-enantiomers. High-performance liquid chromatography is the most widely used technique for the separation of amino acid enantiomers. For that purpose, various chiral deiivatizing reagents and chiral stationary phases are frequently used. The following topics are t)rpical examples of the LC separation and determination of amino acid enantiomers. 

Chiari M, Desperati V, Manera E, LongM R (1998) Combinatorial synthesis of highly selective cyclohexapeptides for separation of amino acid enantiomers by capillary electrophoresis. Anal Chem 70 4967-4973... 

Dzygiel, P., Wieczorek, R, Jonsson, J. A., Milewska, M., and Kafarski, P. (1999). Separation of amino acid enantiomers using supported Uquid membrane extraction with chiral phosphates and phosphonates. Tetrahedron 55, 9923. 

Bertrand M, Chabin A, Brack A, Westall F, Separation of amino acid enantiomers via chiral derivatization and non-chiral gas chromatography. J. Chromatogr. A 2008 1180 131-137. 

De Vault, GL. and Sepaniak, M.J., Two-dimensional capillary eleclrophoresis-thin layer chromatography separations of amino acid enantiomers using electrofilament transfer, J. Micro. Sep., 12 419, 2000. 

Separation of Amino Acid Enantiomers on the Commercial Chiral... 

SEPARATION OF AMINO ACID ENANTIOMERS ON THE COMMERCIAL CHIRAL PLATES... 

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