Separation of amino acids, their derivatives and enantiomers by impregnated TLC

The present state of TLC with respect to separation of amino acids, their d ifferent derivatives and their enantiomers by the technique of impregnation is discussed. The main approaches to impregnation viz. mixing of a suitabl e reagent with the adsorbent prior to plate-making, immersion of the untrea ted plate in the solution of impregnating reagent prior to development, and modification of the adsorbent, have been identified and discussed for each class of these compounds. The role of impregnation in resolving enantiomer s or in improving the separation of mixtures of amino acids or their deriva tives in terms of ion pairing, complex formation, ligand exchange or other steric interactions has been elaborated in each category. Copyright (C): 20 01 John Wiley & Sons, Ltd.