Kinetics of nanopore transport

Abstract

A nonlinear kinetic exclusion model is used to study osmosis and pressure driven flows through nearly single file pores such as antibiotic channels, aquaporins, zeolites and nanotubules. Two possible maxima in the steady state flux as a function of pore-solvent affinity are found. For small driving forces, the linear macroscopic osmotic and hydraulic permeabilities $P_{os}$ and $L_{p}$, are defined in terms of microscopic kinetic parameters. The dependences of the flux on activation energies, pore length and radius, and driving forces are explored and Arrhenius temperature dependences derived. Reasonable values for the physical parameters used in the analyses yield transport rates consistent with experimental measurements. Experimental consequences and interpretations are examined, and a straightforward extension to osmosis through disordered pores is given.