Thermodynamics of Binding of Aromatic Amino Acids to α-, β- and γ-cyclodextrins

Abstract

AbstractThe thermodynamics of the binding of aromatic amino acids, i.e., tryptophan, phenylalanine and tyrosine to α-, β- and γ-cyclodextrin were investigated by microcalorimetry. Heat was evolved following the interaction of tryptophan and tyrosine with α- and β-cyclodextrins but not with γ-cyclodextrin.Phenylalanine only appeared to react with γ-cyclodextrin. Human serum albumin contains these amino acids but the heat evolves following interaction with α and β-cyclodextrins was much lower than that evolved with the individual amino acids. No heat was evolved following the interaction of γ-cyclodextrin with the albumin.