Thin-layer ligand-exchange

Thin-layer Ligand-exchange Chronutt raphy... 

In contrast, CSPs have achieved great repute in the chiral separation of enantiomers by chromatography and, today, are the tools of the choice of almost all analytical, biochemical, pharmaceutical, and pharmacological institutions and industries. The most important and useful CSPs are available in the form of open and tubular columns. However, some chiral capillaries and thin layer plates are also available for use in capillary electrophoresis and thin-layer chromatography. The chiral columns and capillaries are packed with several chiral selectors such as polysaccharides, cyclodextrins, antibiotics, Pirkle type, ligand exchangers, and crown ethers. 

Such cases can be encountered in the case of thin-layer chromatographic separation of amino acids, using copper complexes of long chain amino acids as chiral additives via a ligand exchange approach. The copper complexes of alkyl amino acid chiral additives are so strongly adsorbed on the RP stationary phase that they act as a chiral stationary phase [154-156]. 

K. Gunter, Thin layer chromatographic resolution via ligand exchange, /. Chromatogr. 448 (1988), 11. 

Ligand-exchange chromatography on cation-exchange materials has been used as a separation technique for PASHs, sulfides, polysulfides, and thiols in the petrol industry. The method is only partly suitable for thiols and disulfides, and the retention of compounds is only sufficient in individual cases for the clear separation of compounds. On the other hand, some substances showed small recoveries due to very strong binding to the stationary phases. Paper and thin-layer chromatography have been used as preexperimental qualitative tests in this field. 

Kaimai, T. and Matsunaga, A., Determination of sulfur compounds in high-hoihng petroleum destillates by ligand-exchange thin-layer chromatography. Anal. Chem., 50, 268-270, 1978. 

XII. THIN-LAYER ENANTIOMERIC RESOLUTION VIA LIGAND EXCHANGE... 

Gunther, K., Thin-layer chromatographic enantiomeric resolution via ligand exchange, J. Chromatogr, 448,11-30,1988. 

Gunther, K., Martens, J. and Schickedanz, M., Thin layer chromatographic enantiomer separation by using ligand exchange, Angew. Chem., 96, 514—515, 1984. 

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