Fluorescence of Oligomers that Contain Catechin or Epicatechin

Abstract

Steady state and time resolved fluorescence of monodisperse oligomers of catechin and epicatechin is useful for the study of proanthocyanidins. The quantum yields for fluorescence have been used to measure the number average degree of polymerization of oligomeric procyanidins. The method requires calibration with a known sample. Quenching of the fluorescence by small molecules can be complex because the mechanisms may involve a mixture of static and dynamic quenching. The anisotropy of the fluorescence of a series of oligomers in viscous media reveals the existence of electronic energy migration in these molecules. Analysis of the time dependence of the decay of the fluorescence from dimers has been used to assess the relative populations of the two rotational isomers at the interflavan bond.