Analytical Method for Intermembrane Transfer and Flip-flop of Phospholipids by Small-angle Neutron Scattering

Small-angle neutron scattering (SANS) is a technique used for submicron-scale structural analysis of soft matter and can also be used to evaluate dynamics by taking advantage of the large difference in the scattering length between hydrogen and deuterium. The author’s group has succeeded in determining the rates of intervesicular transfer and transbilayer transfer (flip-flop) of phospholipids in vesicles using this method for the first time and has clarified the differences in these rates depending on the type of phospholipids, as well as the lipid transport activity of phospholipid transfer proteins and the induction of phospholipid flip-flop by transmembrane peptides. This technique is now being implemented by many SANS users. This comprehensive paper presents details and examples of this technique.