title: Fluorescence quenching studies on the interaction of riboflavin with tryptophan and its analytical application.
abstract: The ineraction between riboflavin (RBF) and tryptophan (Trp) was investigated using fluorescence spectroscopy and UV-vis absorption spectroscopy under physiological conditions. The fluorescence of Trp was quenched by RBF via dynamic quenching, which was analyzed using the Stern-Volmer relation. The value of the Forster distance R0 (2.31 nm) was obtained according to the Forster's theory of nonradiative energy transfer. Under physiological conditions, a linear relationship could be established between the quenched fluorescence intensity of Trp and the concentration of RBF in the range of 5.8 × 10(-7) -2.0 × 10(-5) mol/L. The detection limit was 1.8 × 10(-7) mol/L. The method was successfully applied to determine riboflavin concentrations in pharmaceutical samples.
authors.affiliation: School of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, China.
authors.forename: Pingping
authors.initials: P
authors.lastname: Li
authors.forename: Shaopu
authors.initials: S
authors.lastname: Liu
authors.forename: Xiaodan
authors.initials: X
authors.lastname: Wang
authors.forename: Zhengqing
authors.initials: Z
authors.lastname: Liu
authors.forename: Youqiu
authors.initials: Y
authors.lastname: He
mesh_terms: D005453:Fluorescence; D015394:Molecular Structure; D012256:Riboflavin / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D014364:Tryptophan / Q000737:chemistry*
chemical_list: D014364:Tryptophan; D012256:Riboflavin