Overall, the diffusion of the smaller lipid-like DiO probe is faster than that of the larger PBd22-PEO14-TMR probe, which would be expected due to the reduced free volume required for the smaller lipid probe to hop laterally between sites in the membrane matrix. The absolute fluorescence recovery of both the lipid and polymer probes also decreases with decreased membrane fluidity: this is likely caused by enhanced photobleaching of these probes in less fluid matrices, resulting in enhanced total bleaching withing the finite system size of a single GUV.