FRAP analysis of lipid diffusion

Intracellular transport is a fundamental process in biology and underlies all eukaryotic cell functions and survival. Intracellular cargo is often enclosed in a fluid lipid membrane. Intriguingly, alterations in membrane fluidity have been linked to aging and neurological disease, where dysfunctions in intracellular transport are also a common and early hallmark. Here, we use planar supported lipid bilayer to model membranes in cells, and we use Fluorescence Recovery After Photobleaching ( FRAP) to analyze lipid diffusion to assess membrane fluidity for a range of lipid compositions. These findings provide a foundation for investigating how altered membrane fluidity may impact intracellular transport and contribute to disease mechanisms.