Figure 4.

FLIM-FRET phasor diagram depicting peak positions of the two-dimensional histogram of transformed donor fluorescence decay functions measured at every pixel of the GUV image. Upper part: fluorescence intensity images of CTxB-488 (donor) stained GUVs at different lipid compositions. GUVs are colabeled with DiD (acceptor). For D, two clusters appeared in the phasor diagram, corresponding to the L_o and L_d phase. The circular line depicts positions of monoexponential decays and position of the acceptor free decay, i.e., no FRET, is marked.