Migration of semiflexible polymers in microcapillary flow
Institut für Festkörperforschung, Forschungszentrum Jülich - 52425 Jülich, Germany, EU
Accepted: 16 June 2010
The non-equilibrium structural and dynamical properties of a semiflexible polymer confined in a cylindrical microchannel and exposed to a Poiseuille flow is studied by mesoscale hydrodynamic simulations. For a polymer with a length half of its persistence length, large variations in orientation and conformations are found as a function of radial distance and flow strength. In particular, the polymer exhibits U-shaped conformations near the channel center. Hydrodynamic interactions lead to strong cross-streamline migration. Outward migration is governed by the polymer orientation and the corresponding anisotropy in its diffusivity. Strong tumbling motion is observed, with a tumbling time which exhibits the same dependence on Peclet number as a polymer in shear flow.
PACS: 47.61.-k – Micro- and nano- scale flow phenomena / 83.10.Rs – Computational simulation of molecular and particle dynamics / 87.15.-v – Biomolecules: structure and physical properties
© EPLA, 2010