Stern-Volmer modeling of steady-state Forster energy transfer between dilute, freely diffusing membrane-bound fluorophores.

Two different metrics are used to assess Forster resonance energy transfer (FRET) between fluorophores in the steady state: (i) acceptor-quenching of donor fluorescence E (also known as transfer efficiency) and (ii) donor-excited acceptor fluorescence F(A) (Dex). While E is still more widely used, F(A) (Dex) has been gaining in popularity for practical reasons among experimentalists who study biomembranes. Here, for the special case of membrane-bound fluorophores, we present a substantial body of experimental evidence that justifies the use of simple Stern-Volmer expressions when modeling either FRET metric under dilute-probe conditions.

High-resolution mapping of phase behavior in a ternary lipid mixture: do lipid-raft phase boundaries depend on the sample preparation procedure?

For some time now, we have been using a fluorescence resonance energy transfer (FRET)-based strategy to conduct high-resolution studies of phase behavior in ternary lipid-raft membrane mixtures. Our FRET experiments can be carried out on ordinary, polydisperse multilamellar vesicle suspensions, so we are able to prepare our samples according to a procedure that was designed specifically to guard against artifactual phase separation. In some respects (i.