Microanalysis of proteins and peptides. I. Enhancement of the fluorescence intensity of dansyl amino acids and dansyl proteins in aqueous media and its application to assay of amino acids and proteins.

Abstract

The fluorescence of dansyl amino acids and dansyl proteins in aqueous media was found to be greatly enhanced by addition of cycloheptaamylose. This finding was successfully applied for improvement of the assay procedure of amino acids and proteins. Dansyl amino acids of 50 picomoles per ml in final concentration was estimated. Interaction of cycloheptaamylose with dansyl amino acids was thermodynamically studied. The entropies and the enthalpies were found to vary with polarities of the dansyl amino acid.