Levich Institute Seminar Announcement, 11/30/2010
Tuesday, 11/30/2010
2:00 PM
Steinman Hall, Room #312
(Chemical Engineering Conference Room)

Professor Eric Shaqfeh
Stanford University
Department of Chemical Engineering

"The Margination of Platelets and Particles in the Blood Microvasculature"


ABSTRACT

Many dispersions of colloidal particles with application in materials processing, biological assays, or medicine, contain elongated particles (e.g. ellipsoidal disks, rods, etc.) Recently these particles have been used in drug delivery applications because of the inability of leukocytes to easily rid them from the circulation. Moreover such particles are useful at the nanoscale for application in cancer therapies, either for detection of tumor vasculature or for the delivery of anti-cancer agents to tumor endothelial cells. Thus, the study of anisotropic particulate flows with adhesion in microchannels especially in mixtures with vesicle flows (i.e. red blood cells) has taken on a particularly important set of engineering applications. In a different, but related context, hemostasis in the small vessels relies on naturally occurring blood particles such as platelets being concentrated near the external regions of the blood flow, i.e. near the vessel walls, and the process by which this occurs has not been understood heretofore, but depends critically on the hematocrit. We will demonstrate via computer simulation that the physical process of margination is a shear-induced diffusion process but in a highly nonNewtonian fluid, where the latter creates new scalings for the diffusivities. In fact, we demonstrate that this aspect of hemostasis depends critically on the properties of the red blood cell membranes through the rheological properties of the averaged fluid behavior.

BRIEF ACADEMIC/EMPLOYMENT HISTORY
  • Doctor of Philosophy, March, 1986 Chemical Engineering, Stanford University
  • Postdoctoral Research|Dept. of Applied Math. & Theor. Physics, Cambridge, Eng- land, 3/86|12/86
  • Member of Technical Sta.|AT&T Bell Laboratories, 1/87|1/90 Department: Lithography and Chemical Engineering, 11543
  • Assistant Professor|Dept. of Chemical Engineering, 1/90|1/95, Stanford University
  • Associate Professor (w/ tenure)|Dept. of Chemical Engineering, 1/1/95|8/31/99, Stanford University
  • Professor |Dept. of Chemical Engineering, 9/1/99|1/1/2001, Stanford University
  • Professor | Depts. of Chemical Engineering and Mechanical Engineering, Stanford University, 1/1/2001| present
  • Associate Chair | Dept. of Chemical Engineering, Stanford University, 9/1/2001| 1/1/2005
  • Professor | Institute of Computational and Mathematical Engineering, Stanford Uni- versity, 11/2004 | present

RECENT RESEARCH INTERESTS:

Professor Shaqfeh's research program includes the study of different areas associated with transport in complex fluids including: a) the occurrence of purely elastic instabilities in polymer flows, b) the micro-dynamics of polymer molecules, including DNA, in nonequilibrium transport, c) the flow behavior of fiber suspensions, d) the general microfluidic flow behavior of complex fluids and, most recently, e) the stability of compressible boundary layer flows. Our approach in these areas includes developing large scale simulations (including both Brownian dynamics and continuum simulation) of poorly understood phenomena and then couple these to detailed experiments to elucidate the important physics in a variety of processes.