Which technique is best for quantifying membrane lipid mobility?
Measuring lipid mobility in living membranes requires optical methods sensitive to diffusion rather than biochemical detection DNA proteins. Fluorescence recovery after photobleaching FRAP uses laser bleaching fluorescent analogs like NBD phosphatidylcholine Bodipy sphingomyelin in defined micron spot monitoring influx unbleached fluorophores over seconds to minutes. Analysis half recovery time yields diffusion coefficient and mobile fraction distinguishing freely diffusing from cytoskeleton anchored immobile pools. Alternative approaches single particle tracking trajectories mean squared disp
Ref: Axelrod et al., Biophys J 1976, FRAP principle measuring lipid diffusion. Lippincott-Schwartz.
