TY  - JOUR
A1  - Cherstvy, Andrey G.
A1  - Chechkin, Aleksei V.
A1  - Metzler, Ralf
T1  - Particle invasion, survival, and non-ergodicity in 2D diffusion processes with space-dependent diffusivity
JF  - Soft matter
N2  - We study the thermal Markovian diffusion of tracer particles in a 2D medium with spatially varying diffusivity D(r), mimicking recently measured, heterogeneous maps of the apparent diffusion coefficient in biological cells. For this heterogeneous diffusion process (HDP) we analyse the mean squared displacement (MSD) of the tracer particles, the time averaged MSD, the spatial probability density function, and the first passage time dynamics from the cell boundary to the nucleus. Moreover we examine the non-ergodic properties of this process which are important for the correct physical interpretation of time averages of observables obtained from single particle tracking experiments. From extensive computer simulations of the 2D stochastic Langevin equation we present an in-depth study of this HDP. In particular, we find that the MSDs along the radial and azimuthal directions in a circular domain obey anomalous and Brownian scaling, respectively. We demonstrate that the time averaged MSD stays linear as a function of the lag time and the system thus reveals a weak ergodicity breaking. Our results will enable one to rationalise the diffusive motion of larger tracer particles such as viruses or submicron beads in biological cells.
KW  - anomalous diffusion
KW  - intracellular-transport
KW  - adenoassociated virus
KW  - infection pathway
KW  - escherichia-coli
KW  - endosomal escape
KW  - living cells
KW  - trafficking
KW  - cytoplasm
KW  - models
Y1  - 2014
U6  - https://doi.org/10.1039/c3sm52846d
SN  - 2046-2069
VL  - 2014
IS  - 10
SP  - 1591
EP  - 1601
PB  - Royal Society of Chemistry
ER  - 
TY  - GEN
A1  - Cherstvy, Andrey G.
A1  - Chechkin, Aleksei V.
A1  - Metzler, Ralf
T1  - Particle invasion, survival, and non-ergodicity in 2D diffusion processes with space-dependent diffusivity
N2  - We study the thermal Markovian diffusion of tracer particles in a 2D medium with spatially varying diffusivity D(r), mimicking recently measured, heterogeneous maps of the apparent diffusion coefficient in biological cells. For this heterogeneous diffusion process (HDP) we analyse the mean squared displacement (MSD) of the tracer particles, the time averaged MSD, the spatial probability density function, and the first passage time dynamics from the cell boundary to the nucleus. Moreover we examine the non-ergodic properties of this process which are important for the correct physical interpretation of time averages of observables obtained from single particle tracking experiments. From extensive computer simulations of the 2D stochastic Langevin equation we present an in-depth study of this HDP. In particular, we find that the MSDs along the radial and azimuthal directions in a circular domain obey anomalous and Brownian scaling, respectively. We demonstrate that the time averaged MSD stays linear as a function of the lag time and the system thus reveals a weak ergodicity breaking. Our results will enable one to rationalise the diffusive motion of larger tracer particles such as viruses or submicron beads in biological cells.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 168 
KW  - adenoassociated virus
KW  - anomalous diffusion
KW  - cytoplasm
KW  - endosomal escape
KW  - escherichia-coli
KW  - infection pathway
KW  - intracellular-transport
KW  - living cells
KW  - models
KW  - trafficking
Y1  - 2014
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-74021
IS  - 168
SP  - 1591
EP  - 1601
ER  -