Nanoscopic Lipid Domains Characterized by Iscat Microscopy

Characterizing the lateral organization of lipid membranes is important for understanding the function of cell membranes. Several groups have reported submicron heterogeneity in model membranes, using techniques such as neutron scattering, x-ray scattering, FRET, or AFM. Here, we study these systems using iSCAT microscopy, a recently developed technique that images the differences in light scattering from different regions of a sample. This technique is capable of label-free detection of nanometer-scale lipid domains, and is compatible with fully hydrated, micron-scale membranes. This allows us to directly measure the membrane organization and dynamics, and to compare data from the same technique across widely different length scales.