Nanoscale Modeling of Flow of Macromolecules Through Microfluidic Devices

University Of Wisconsin-Madison, Madison WI

Investigators

Abstract

Microfluidic devices are rapidly finding an increasing number of applications in biology, chemistry, and medicine, to name a few. These devices rely on the ability to control the flow and transport of fluids and macromolecules through micron and nanometer scale geometries. As the ability to manipulate and process materials at the sub-micron level advances, so will the demand to make a priori predictions of molecular behavior in flow processes on this scale. In the proposed work, a large-scale computational approach is adopted to model the transport of fluids containing long-chain molecules through microdevices of arbitrary geometry. One overall goal is to develop efficient Brownian dynamics methods for the molecular study of: (1) long-chain flexible molecules in flow, fully accounting for hydrodynamic, excluded volume and electrostatic interactions; (2) assemblages of semiflexible polymers, accounting for interparticle interactions that often dominate flow behavior; (3) hydrodynamic interaction effects on dynamics of chain molecules near solid surfaces; (4) coupling of nanoscale Brownian dynamics simulations and continuum fluid mechanics simulations (for self-consistent solution of complex problems). A general approach to multi-scale computational fluid dynamics will be developed, in which microstructural, nanoscale simulations are seamlessly and efficiently integrated into full scale flow simulations for design of microfluidic processes. Our goal is to develop the fundamentals for development of a general nanoscale process simulator, akin to those currently used in design of large-scale industrial processes. In this project, these advances will be applied to improve the understanding of polyelectrolytes in flow; to study the flow of DNA solutions through microchannels and near surfaces; to study the interaction between flow and nanostructure in geometries characteristic of microfluidic devices.