TY - JOUR
A1 - Ghosh, Surya K.
A1 - Cherstvy, Andrey G.
A1 - Metzler, Ralf
ED - Metzler, Ralf
T1 - Non-universal tracer diffusion in crowded media of non-inert obstacles
JF - Physical Chemistry Chemical Physics
N2 - We study the diffusion of a tracer particle, which moves in continuum space between a lattice of excluded volume, immobile non-inert obstacles. In particular, we analyse how the strength of the tracer–obstacle interactions and the volume occupancy of the crowders alter the diffusive motion of the tracer. From the details of partitioning of the tracer diffusion modes between trapping states when bound to obstacles and bulk diffusion, we examine the degree of localisation of the tracer in the lattice of crowders. We study the properties of the tracer diffusion in terms of the ensemble and time averaged mean squared displacements, the trapping time distributions, the amplitude variation of the time averaged mean squared displacements, and the non-Gaussianity parameter of the diffusing tracer. We conclude that tracer–obstacle adsorption and binding triggers a transient anomalous diffusion. From a very narrow spread of recorded individual time averaged trajectories we exclude continuous type random walk processes as the underlying physical model of the tracer diffusion in our system. For moderate tracer–crowder attraction the motion is found to be fully ergodic, while at stronger attraction strength a transient disparity between ensemble and time averaged mean squared displacements occurs. We also put our results into perspective with findings from experimental single-particle tracking and simulations of the diffusion of tagged tracers in dense crowded suspensions. Our results have implications for the diffusion, transport, and spreading of chemical components in highly crowded environments inside living cells and other structured liquids.
KW - fluorescence correlation spectroscopy
KW - single-particle tracking
KW - anomalous diffusion
KW - living cells
KW - physiological consequences
KW - langevin equation
KW - infection pathway
KW - excluded volume
KW - brownian-motion
KW - random-walks
Y1 - 2014
SN - 1463-9076
VL - 3
IS - 17
SP - 1847
EP - 1858
PB - The Royal Society of Chemistry
CY - Cambridge
ER -
TY - GEN
A1 - Ghosh, Surya K.
A1 - Cherstvy, Andrey G.
A1 - Metzler, Ralf
T1 - Non-universal tracer diffusion in crowded media of non-inert obstacles
N2 - We study the diffusion of a tracer particle, which moves in continuum space between a lattice of excluded volume, immobile non-inert obstacles. In particular, we analyse how the strength of the tracer–obstacle interactions and the volume occupancy of the crowders alter the diffusive motion of the tracer. From the details of partitioning of the tracer diffusion modes between trapping states when bound to obstacles and bulk diffusion, we examine the degree of localisation of the tracer in the lattice of crowders. We study the properties of the tracer diffusion in terms of the ensemble and time averaged mean squared displacements, the trapping time distributions, the amplitude variation of the time averaged mean squared displacements, and the non-Gaussianity parameter of the diffusing tracer. We conclude that tracer–obstacle adsorption and binding triggers a transient anomalous diffusion. From a very narrow spread of recorded individual time averaged trajectories we exclude continuous type random walk processes as the underlying physical model of the tracer diffusion in our system. For moderate tracer–crowder attraction the motion is found to be fully ergodic, while at stronger attraction strength a transient disparity between ensemble and time averaged mean squared displacements occurs. We also put our results into perspective with findings from experimental single-particle tracking and simulations of the diffusion of tagged tracers in dense crowded suspensions. Our results have implications for the diffusion, transport, and spreading of chemical components in highly crowded environments inside living cells and other structured liquids.
T3 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 186
KW - escence correlation spectroscopy
KW - single-particle tracking
KW - anomalous diffusion
KW - living cells
KW - physiological consequences
KW - langevin equation
KW - infection pathway
KW - excluded volume
KW - brownian-motion
KW - random-walks
Y1 - 2014
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-77128
SP - 1847
EP - 1858
PB - The Royal Society of Chemistry
CY - Cambridge
ER -