Seminário: Hydrodynamics of poroelastic hydrogels: theory and biomicrofluidic applications

Resumo: Hydrogels are polymer networks swollen by an aqueous solvent. For their softness, porosity and biocompatibility, they are finding exciting applications in many fields, e.g., as sensor and actuator, and as cell scaffolds in tissue engineering. Two aspects of hydrogel mechanics have been studied separately in the past. The first is the swelling of gels in a quiescent solvent bath triggered by an environmental stimulus such as a change in temperature or pH, and the second is the solvent flow around and into a gel, driven by an external pressure gradient or moving boundary. As both aspects coexist and indeed interact with each other in emerging applications, we have developed a poroelasticity model that integrates these two aspects into a single framework.

In this talk, I will first describe the theoretical model, and then demonstrate how the coupling between swelling and flow gives rise to novel physics in simple flows. In particular, we use finite elements to solve for flow through gels containing biological cells modeled as hyperelastic inclusions. In geometries that occur frequently in microfluidic cell cultures, we examine how the perfusion engenders interstitial flow in the gels that displaces and deforms the embedded cells. This provides a tool to design the geometry and flow conditions to achieve optimal flow and stress fields inside the hydrogels and around the cells.

CV: James J. Feng received his B.S. (1985) and M.S. (1988) degrees from Peking University in Beijing, and his Ph.D. (1995) from the University of Minnesota, all in Fluid Mechanics. After a postdoctoral stint at the University of California, Santa Barbara, he was appointed an associate professor in 1998 at the Levich Institute for Physicochemical Hydrodynamics in New York City. In 2004, he moved to the University of British Columbia (UBC) in Vancouver, Canada, with a joint appointment in Chemical and Biological Engineering and Mathematics. He is a fellow of the American Physical Society, and a recipient of the CAIMS Research Prize (Canadian Applied and Industrial Mathematics Society). His current research covers multiphase and interfacial fluid dynamics, and biomechanics of cells and tissues.

Serviço de Comunicação Institucional
secin@lncc.br