Energy transfer in biflavinyl compounds as studied with fluorescence depolarization

Light absorption, fluorescence and fluorescence anisotropy measurements were performed on two different, dimeric flavin models and on the parent isoalloxazine derivative, either dissolved in chloroform or in the rigid matrix polymethylmetacry- late (PMMA). The optical results in fluid solution and the fluorescence depolarization in PMMA could be well explained by a different intramolecular equilibrium orientation of the flavin constituents. The rate constant for radiationless energy transfer among the flavins within the dimers followed directly from an analysis of the anisotropy decay.