Chemical Engineering Seminar

Abstract: Transport of nanoparticles affects applications ranging from targeted drug delivery to point-of-care diagnostics to processing of nanocomposite materials. In each of these applications, nanoparticles must be transported through a macromolecule-laden fluid to reach the desired target, whether a cancerous tumor, a membrane, or a polymer melt. For large particles, the surrounding medium is effectively homogeneous across the surface of the particle, so that the transport properties can be directly related to the bulk fluid properties. For nanoparticles, however, the particle size is comparable to the length scales of heterogeneities in the fluid so that the particle dynamics decouple from bulk properties and are poorly understood. Here, we combine microscopy and scattering experiments with molecular simulation to investigate how nanoparticles transport through polymer solutions, which serve as a tunable model of viscoelastic liquids, and examine how the dynamics of the nanoparticles are coupled to relaxations of the surrounding liquid. I will focus on our recent work probing transport through solutions of synthetic and natural polyelectrolytes, in which charges along the polymer backbone alter the polymer's structure and dynamics. The physics elucidated in these studies will grant better control over the transport and dispersion of nanoparticles through complex, heterogeneous materials.

Bio: Jacinta Conrad is a physical scientist studying transport and dynamics within soft, complex materials and matrices. Using a broad range of microscopy, rheology, scattering, and computational methods, her group seeks to understand how microscale particles, including colloids, nanoparticles, bacteria, viruses, and proteins, explore and/or transport through confined and crowded environments. Insights gained from fundamental studies of these non-equilibrium processes inform the design of materials for preventing fouling and corrosion, for remediating environmental damage, and for sensitively diagnosing disease. She earned an SB in Mathematics from the University of Chicago and MA and PhD degrees in Physics from Harvard. She worked as a postdoctoral associate in Materials Science and Engineering at the University of Illinois at Urbana-Champaign before starting her faculty position at the University of Houston (UH). Currently, she is the Frank M. Tiller Professor of Chemical & Biomolecular Engineering at UH, an Executive Editor at ACS Applied Nano Materials, and a Fellow of the American Association for the Advancement of Science (AAAS), the American Physical Society (APS), and the Society of Rheology.