Resonance energy transfer study using a rhenium metal-ligand lipid conjugate as the donor in a model membrane

We measured steady state and time-resolved resonance energy transfer between donors and acceptors in model membranes. The donor was a long lifetime rhenium-lipid complex, which displayed a mean lifetime of 1 μs and lifetime components as long as 3 μs in the labeled DOPC membranes. The transfer efficiencies were found to be substantially larger than those predicted without consideration of lateral diffusion. The larger transfer efficiencies are consistent with a mutual lateral diffusion coefficient in the membrane near 2x10^-8 cm²/s. These results demonstrate that lateral diffusion in membranes can be detected with μs lipid probes. Copyright (C) 1999 Elsevier Science Ireland Ltd.