Effects of Varied Tyrosine Concentrations on FEEM and SFS of Constant Tryptophan concentration

Abstract

In recent years, the 3D fluorescence excitation emission spectrum has been widely applied into the analysis of the properties of soluble organic matter in water bodies, but there is very little research on the fluorescence properties of protein residues in water quality detection by Fluorescence Excitation Emission Matrix (FEEM), and synchronous fluorescence excitation emission spectra (SFS). The characteristics of luminescent of amino acids, including tryptophan, tyrosine and phenylalanine, where tryptophan and tyrosine fluorescence are relatively strongest, and the effects of tyrosine on the fluorescence properties of tryptophan are seldom discussed in different mixing ratios for both amino acids. The fluorescent peak positions and intensities of the three amino acids are related to the angle size of conjugate plane, N hybrids and hydroxyls on benzene rings. When the ratio of tyrosine to tryptophan content is less than 150:100, tryptophan will quench the fluorescent peak of the tyrosine. Constant tryptophan content, tyrosine at excitation wavelength of 228 nm, its concentration changes with the corresponding fluorescence intensity has a good linear relationship; however, at 276-278 nm of tyrosine, the varied concentrations and fluorescence intensities are opposite.