Small-angle scattering from homogenous and heterogeneous lipid bilayers

Advances in colloid and interface science have stimulated a renewed interest in the study of lipid-water systems. At the same time, much progress has been made in regards to the analysis of small-angle X-ray and neutron scattering data. The popularity of small-angle scattering for the study of biologically relevant materials stems from the fact that it provides detailed information on the size, shape, and conformation of molecular assemblies in solution. Additionally, neutron scattering has the capability to accentuate, or nullify, the scattering from individual parts of a macromolecular complex with its unique ability to distinguish between hydrogen and its isotope deuterium. As a result, structural biophysics has taken advantage of recent developments in small-angle scattering to accurately determine the structure of lipid bilayers in both the transverse and lateral directions. An example is the joint refinement of X-ray and neutron scattering data, which has been used to improve the values of lipid areas that are commonly used in molecular dynamics simulations. Advances in neutron scattering theory have also made possible the determination of the membrane's in-plane organization by enabling the detection and characterization of nanoscopic domains.