Fluid Dynamics Seminar

Monday, Nov 2, 2009, 4:00 PM
Cullimore Lecture Hall, Room 611
New Jersey Institute of Technology


Manipulating Single Polymer Chains and Single Particles in Flow

Chalres Schroeder


Department of Chemical and Biomolecular Engineering, University of Illinois, Urbana-Champaign



Single molecule and single particle techniques offer a powerful approach to investigate complex physical and biological processes. In this work, we discuss two studies in polymer dynamics facilitated by single molecule fluorescence microscopy and Brownian dynamics simulations of polymer chains. In the first study, the phenomenon of polymer conformation hysteresis is discussed and explored using experiments and simulations. In addition, we discuss the characteristic periodic motion of polymer chains in simple shear flow. The discussion of polymer chain dynamics will conclude with new directions for single molecule polymer studies, including extension of experimental studies to a new class of flexible polymer chains. In the second part of the talk, we present a novel method of trapping arbitrary particles, single cells or molecules. The ability to trap individual particles or cells has revolutionized many fields of science during the last two decades. Here, we describe an alternative trapping method, the hydrodynamic trap, which is based on the sole action of hydrodynamic forces in a microfluidic device. This technique offers a new venue for observation of biological or colloidal materials without surface immobilization, eliminates potentially perturbative optical, magnetic and electric fields, and provides the capability to change surrounding medium conditions of the trapped object.