Hydrodynamic and entropic effects on colloidal diffusion in corrugated channels.

ABSTRACT: In the absence of advection, confined diffusion characterizes transport in many natural and artificial devices, such as ionic channels, zeolites, and nanopores. While extensive theoretical and numerical studies on this subject have produced many important predictions, experimental verifications of the predictions are rare. Here, we experimentally measure colloidal diffusion times in microchannels with periodically varying width and contrast results with predictions from the Fick-Jacobs theory and Brownian dynamics simulation. While the theory and simulation correctly predict the entropic effect of the varying channel width, they fail to account for hydrodynamic effects, which include both an overall decrease and a spatial variation of diffusivity in channels. Neglecting such hydrodynamic e

SUBMITTER: Yang X 

PROVIDER: S-EPMC5594686 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature