Actively Controlled Transport with Molecular Assemblies

University Of Notre Dame, Notre Dame IN

Investigators

Abstract

Professor Paul W. Bohn of the University of Notre Dame is supported by the Chemical Measurement and Imaging Program in the Division of Chemistry to develop multifunctional nanoscale fluidic devices. The project investigates how devices can be constructed so that a single structure can simultaneously switch fluid flow, sense the presence of specific molecules and subsequently subject these molecules to treatment - perhaps remediation of an environmental pollutant or destruction of a harmful biomolecule circulating in the body. Electrical potentials applied to different regions of the device cause small volumes of fluid to move through specific channels for sensing and treatment. The projects seek to combine this electrically-activated fluid flow with electrochemical reactions and with sensitive methods of chemical sensing - based either on the luminescence of the molecules after electrochemical reaction or the interaction of high frequency excitations in metals with the surrounding fluid. One critical challenge in carrying out the electrochemical reactions is that they must occur far from ground potential, where such reactions routinely are carried out. Thus, the project aims to develop new ways to perform electrochemical transformations at arbitrarily large voltages. The second challenge is that because the structures are so small, only a tiny number of molecules may react at any given time. Thus, the project seeks to develop new highly sensitive methods of following electron transfer reactions that are applicable to ultrasmall samples, even to single molecules. The broader impact of this program on society is felt in three ways. First, the scientific work addresses the control and manipulation of fluid flow in miniature analytical devices, a problem of growing interest to the international scientific community. Second, the scientific work contributes to scientific human resource development through the involvement of a diverse range of students with participation from under-represented groups and women. The third area lies in helping students learn about the international dimension of science through a student exchange with one of the world's leading bioelectrochemistry laboratories at Cambridge University, Cambridge, UK.