title: Diffusion NMR studies of macromolecular complex formation, crowding and confinement in soft materials.
abstract: Label-free methods to obtain hydrodynamic size from diffusion measurements are desirable in environments that contain multiple macromolecular species at a high total concentration: one example is the crowded cellular environment. In complex, multi-species macromolecular environments - in this article, we feature aqueous systems involving polymers, surfactants and proteins - the link between dynamics and size is harder to unpack due to macromolecular crowding and confinement. In this review, we demonstrate that the pulsed-field gradient NMR technique, with its spectral separation of different chemical components, is ideal for studying the dynamics of the entire system simultaneously and without labelling, in a wide range of systems. The simultaneous measurement of the dynamics of multiple components allows for internal consistency checks and enables quantitative statements about the link between macromolecular dynamics, size, complex formation and crowding in soft materials.
authors.affiliation: Department of Physics and Physical Oceanography, Memorial University, St. John's, Newfoundland and Labrador, Canada.
authors.forename: Suliman
authors.initials: S
authors.lastname: Barhoum
authors.affiliation: Department of Physics and Physical Oceanography, Memorial University, St. John's, Newfoundland and Labrador, Canada.
authors.forename: Swomitra
authors.initials: S
authors.lastname: Palit
authors.affiliation: Department of Physics and Physical Oceanography, Memorial University, St. John's, Newfoundland and Labrador, Canada.
authors.forename: Anand
authors.initials: A
authors.lastname: Yethiraj
mesh_terms: D055592:Biophysical Phenomena; D004058:Diffusion; D005362:Ficoll / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D010455:Peptides / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry*; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D013501:Surface-Active Agents / Q000737:chemistry*; D014867:Water
chemical_list: D010455:Peptides; D011108:Polymers; D011506:Proteins; D013501:Surface-Active Agents; D014867:Water; D005362:Ficoll; D012967:Sodium Dodecyl Sulfate; D011092:Polyethylene Glycols
keywords: Complex formation; Confinement; Crowding; Pulsed-field gradient NMR; Soft materials