Figure 5.
Probe partition coefficients do not show abrupt transitions along a ρ-trajectory. Partition coefficient Kp between Ld and Lo phases for: (A) the fluorescence probe BODIPY-PC in bSM/DOPC/POPC/chol, and (B) the spin-label probe 16PC in DSPC/DOPC/POPC/chol. Within the ρ-window where domain size exhibits an abrupt increase (shaded regions), changes in Kp are gradual. Also shown in (A) are: (upper-left inset) the fluorescence intensity (symbols) and fit to a partitioning model (solid line) of Bodipy-PC along a thermodynamic tieline at ρ = 0, and (lower-right inset) fluorescence micrograph revealing the partitioning of Bodipy-PC in a GUV at ρ = 0.9 (scale bars, 5 μm, temperature 23°C). For details, see the Supporting Material.