Macromolecular Interactions: Light Scattering

Abstract

Static light scattering (SLS) is a spectroscopic technique for determination of molar masses (molecular weights) and radii of gyration for macromolecules in solution. Dynamic light scattering (DLS) measurement allows determination of translational diffusion coefficient and hydrodynamic radius. Measurement of molar mass from SLS experiment determines the oligomeric state and thus provides association stoichiometry for biological macromolecules such as native and modified proteins and their complexes, nucleic acids as well as phospholipid vesicles, viruses or drug delivering nanoparticles. Both static and DLS are routinely used to assess monodispersity (homogeneity with respect to molar mass or size) of protein stocks prepared for structural studies. Both homo- and hetero-association of proteins can be detected and quantitatively characterized from light scattering measurements performed at various concentrations.