Hui Yang, Xue Xiao, Xuesong Zhao, Yan Wu
This paper presents the intrinsic fluorescence spectra characteristics of tryptophan, tyrosine and phenyloalanine measured with 3D fluorescence spectrophotometer. Two strong fluorescence peaks of tryptophan locate at ex/ em=230/348nm and 280/348nm, three strong fluorescence peaks of tyrosine locate at ex/ em=202/304nm, ex/ em=220/304nm and 275/304nm, and two fluorescence peaks of phenyloalanine locate at ex/ em=210/280nm and ex/ em=260/280nm were found. The linear relationship of fluorescence intensity to solution concentration were also observed in condition of low solution concentration. The influence of pH of solution to the fluorescence intensity was also measured and discussed.