Biopolymer gels and ions

PMSE 189

Ferenc Horkay, horkay@helix.nih.gov, Laboratory of Integrative and Medical Biophysics, National Institutes of Health, NICHD, 13 South Drive, Bethesda, MD 20892
In biological systems structure formation is the result of a complex interplay between different factors that depends on the interactions between the ions and the charged macromolecules. Understanding of the interaction of polyelectrolytes with ions could help to clarify the basic physics of ion binding as well as the mechanism of various biological processes. The complexity of the phase behavior of biopolymer systems and the large number of components make necessary to investigate the structure and physical properties on all length scales from atomic level up to the macroscopic level. In the present work we report small angle neutron scattering measurements and osmotic swelling pressure measurements for synthetic and biopolymer gels. It is demonstrated that combination of scattering and osmotic measurements reveals the effect of ions on the characteristic length scales that govern the osmotic concentration fluctuations, and yields valuable structural information on both molecular and supermolecular levels.