Author: vjohn at nsf18 Date: 7/8/98 9:19 AM Priority: Normal TO: adthomas Subject: 9815482 Hillier - Abstract Message Contents Abstract Proposal No: 9815482 Proposal Type: SGER Principal Investigator: Andrew Hillier Affiliation: University of Virginia This grant is awarded through the Separations and Purification Program sub-element of the Interfacial, Transport and Separations Program of the Chemical and Transport Systems Division. The principal investigator is Dr. Andrew Hillier at the University of Virginia. The research is directed towards the development of a class of adaptive materials whose binding characteristics respond to changes in their local environment. These materials are particularly attractive in chemical separation as their environmental sensitivity can be used as either a signal of analyte binding or as a means of actively controlling chemical affinity. Specifically, a series of supramolecular compounds will be constructed based on macrocylces of cation-selective polyethers and anion-selective polyammoniums that are tethered to redox-active metallocenes or optically-responsive diazobenzenes. The chemical affinity of the macrocycle will be tuned by varying its chemical composition and ring size to adjust selectivity for small, inorganic ions ranging from halides to transition metals. The impact of optically electrochemically-induced switching of the binding behavior in these materials will be investigated. The separation characteristics of these macromolecules will be examined in aqueous solutions while incorporated into liquid and bilayer lipid membranes. This work provides a novel class of materials with highly controllable chemical binding behavior and a switching mechanism that can be externally triggered to actively control membrane-based separation processes and design novel chemical sensing techniques. The work will lead to the discovery and implementation of new materials that provide a specifically controlled local environment for manipulation of chemical affinity and transport properties.
