Layers ligand-exchange chromatography

Macherey-Nagel, and HPTLC-Chir, Merck, Germany) for ligand-exchange chromatography. The chiral layer on the latter plates is combined with a so-called concentrating zone. ... 

Fig.l Classes of chiral organic compounds resolved (a) by ligand-exchange chromatography on Chiral and HPTLC Chir plates and (b) on MCTA layers. 

Chemically modified layers CHIRalplate Enantiomer separation based on ligand exchange chromatography Chiral amino acids, a-hydroxy-carboxyhc acids and other compounds which can form chelate complexes with Cu(II) ions... 

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. 

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. 

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. 

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