Use of the fluorescence quantum yield for the determination of the number-average molecular weight of polymers of epicatechin with 4β→8 interflavin bonds

Abstract

Excitation at 280 nm produces a structureless emission band with a maximum at 321-324 nm for dilute solutions of catechin, epicatechin, and their oligomers in l,4-dioxane or water. The fluorescence quantum yield, Q, has been measured in these two solvents for five dimers, a trimer, a tetramer, a pentamer, a hexamer, and a polymer in which the monomer units are catechin and/or epicatechin. In a homologous series of monodisperse oligomers in which epicatechin units are connected by interOavan bonds with 4β→8 stereochemistry Q, is found to be inversely proportional to the degree of polymerization. Measurement of Q for a polydisperse sample of this polymer yields the number-average degree of polymerization.

Citation

Cho, D.; Mattice, W.L.; Porter, L.J.; Hemingway, Richard W. 1989. Use of the fluorescence quantum yield for the determination of the number-average molecular weight of polymers of epicatechin with 4β→8 interflavin bonds. Polymer 30:1955-1958