Some Features of Non-Exchangeable Sorption of Tryptophan: The Role of Polar and π–π Interactions

The non-exchangeable sorption of tryptophan by the AV-17-2P anion exchanger from solutions of different compositions was studied. The sorption of the amino acid was shown to be independent of the nature of the accompanying component. This was explained by quantum-chemical modeling, which gave variants of attachment and energy characteristics of the bonds formed in the sorbent phase during non-exchangeable sorption of tryptophan by a highly basic anion exchanger in the salt form. The polar interactions play the major role, and π–π interactions produce an additional effect during the non-exchangeable sorption of amino acids on highly basic aromatic anion exchangers.