Els Fieremans, Dmitry S. Novikov, Jens H. Jensen and Joseph A. Helpern
This Monte Carlo study shows that the Kärger model (KM), although highly idealized, can accurately model the diffusion for a realistic tissue model at long times, provided that the compartment diffusivities are time independent and the permeability is sufficiently low such that the exchange between the compartments is barrier limited. The time dependence of the kurtosis allows one to determine the exchange time. The simulations show, however, that, for more permeable membranes, i.e. when the exchange becomes correlated with diffusion, the KM-derived exchange times are overestimated.