Workshop on Membrane Science
August 17-18, 2004, APS, Argonne, Illinois
Scope
The emerging research topics in membrane science are truly interdisciplinary and represent the interfaces among materials chemistry, physics, molecular biology and medicine. For example, inorganic membranes, owing to their thermal, mechanical, and chemical stability, have been used in many industrial separation processes. Organic membranes are used for a variety of liquid and gas-phase separations and for the extraction of trace organic pollutants from water. The supramolecular architecture of biological systems is based on ultrathin and highly flexible bio-membranes. Most bio-membranes exhibit a universal construction principle: a self assembled bilayer of lipid molecules with many anchored macromolecules. The intent of this workshop is to bring the scientists from these various areas membrane science to identify the research frontiers where collaborative activities using the synchrotron radiation techniques are rewarding. Understanding chemical ordering, pattern formation, kinetics, and dynamics in organic and inorganic membran e structures , as well as the physical interactions between bio-membranes and supramolecules, their dynamics under stimuli, and the formation and structure of ion channels in these bio- membranes forms the basis for discussion at this workshop.
Fundamental understanding will be necessary to control the formation of membranes on all length scales (nano, micro, and macro) whether membranes are fabricated or self-assembled. It is even more challenging to create new types of membranes utilizing the insights obtained by studying biological structures. The new synthesis processes are driven by potential applications where the membrane properties and function are to be integrated from the atomic scale to the macro-scale, which span 7-8 orders of magnitude in length and time scales. The challenge for the workshop participants is to identify key problems where the application of xray analytical tools will enable significant progress in relating structure and function. They will demand high-resolution structure determination in one-, two-, and three-dimensions in the nano-, micro-, and macro-scales, element-specific mapping that are non-destructive and provide real-time information on the kinetics and dynamics in the membranes on multiple scales.Most widely used tools to study membrane structures at the Advanced Photon Source include wide-angle x-ray scattering (WAXS), small-angle x-ray scattering (SAXS), ultra small-angle x-ray scattering (USAXS), grazing-incidence small-angle x-ray scattering (GISAXS), x-ray reflectometry (XRR), x-ray photon correlation spectroscopy (XPCS), grazing-incidence x-ray diffraction (GIXD) and x-ray absorption spectroscopy (XAS). These techniques in the real-time domain give considerable insight into time evolution and molecular interactions in the systems.
The workshop included plenary talks on science overviews of the following topics:
- Structure and dynamics in organic and inorganic membrane systems for technological applications
- Structure and dynamics in synthetic and natural bio - membranes : lipid-lipid , lipid - protein, lipid - nucleic acid interactions, biotechnological applications.
