Interaction of amino acids, N-acetylamino acid esters, thymine and adenine with sephadex LH-20 GEL.

N-Acctyl aromatic amino acid esters, tryptophan, adenine and thymine show
strong retention in Sephadex LH-20 gel in an aqueous phase. The decreased retention
in 6 M urea. the absence of retention in absolute methanol and the increased retention
at higher temperatures in the aqueous phase indicate that hydrophobic interaction is
responsible for the observed retention of the amino acids and their esters in the gel.
Adenine was found to be retained by polar interaction in the gel. The increased retention
of the solutes in the presence of different electrolytes suggests that the lyotropic
effect is more important than the ionic strength effect. The relevance of the results
obtained with amino acids and esters to the conformational aspects of proteins in
aqueous solution is discussed.