Self-subdiffusion in solutions of star-shaped crowders: non-monotonic effects of inter-particle interactions
We examine by extensive computer simulations the self-diffusion of anisotropic star-like particles in crowded two-dimensional solutions. We investigate the implications of the area coverage fraction ϕ of the crowders and the crowder–crowder adhesion properties on the regime of transient anomalous di...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2015-01-01
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| Series: | New Journal of Physics |
| Subjects: | |
| Online Access: | https://doi.org/10.1088/1367-2630/17/11/113028 |
| _version_ | 1797751120555147264 |
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| author | Jaeoh Shin Andrey G Cherstvy Ralf Metzler |
| author_facet | Jaeoh Shin Andrey G Cherstvy Ralf Metzler |
| author_sort | Jaeoh Shin |
| collection | DOAJ |
| description | We examine by extensive computer simulations the self-diffusion of anisotropic star-like particles in crowded two-dimensional solutions. We investigate the implications of the area coverage fraction ϕ of the crowders and the crowder–crowder adhesion properties on the regime of transient anomalous diffusion. We systematically compute the mean squared displacement (MSD) of the particles, their time averaged MSD, and the effective diffusion coefficient. The diffusion is ergodic in the limit of long traces, such that the mean time averaged MSD converges towards the ensemble averaged MSD, and features a small residual amplitude spread of the time averaged MSD from individual trajectories. At intermediate time scales, we quantify the anomalous diffusion in the system. Also, we show that the translational—but not rotational—diffusivity of the particles D is a nonmonotonic function of the attraction strength between them. Both diffusion coefficients decrease as the power law $D(\phi )\sim {(1-\phi /{\phi }^{\star })}^{2...2.4}$ with the area fraction ϕ occupied by the crowders and the critical value ${\phi }^{\star }.$ Our results might be applicable to rationalising the experimental observations of non-Brownian diffusion for a number of standard macromolecular crowders used in vitro to mimic the cytoplasmic conditions of living cells. |
| first_indexed | 2024-03-12T16:43:50Z |
| format | Article |
| id | doaj.art-b9e7f9f1b54e48428543ac9e485a4f28 |
| institution | Directory Open Access Journal |
| issn | 1367-2630 |
| language | English |
| last_indexed | 2024-03-12T16:43:50Z |
| publishDate | 2015-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | New Journal of Physics |
| spelling | doaj.art-b9e7f9f1b54e48428543ac9e485a4f282023-08-08T14:22:01ZengIOP PublishingNew Journal of Physics1367-26302015-01-01171111302810.1088/1367-2630/17/11/113028Self-subdiffusion in solutions of star-shaped crowders: non-monotonic effects of inter-particle interactionsJaeoh Shin0Andrey G Cherstvy1Ralf Metzler2Institute for Physics & Astronomy, University of Potsdam , 14476 Potsdam-Golm, Germany; Max Planck Institute for the Physics of Complex Systems , 01187 Dresden, GermanyInstitute for Physics & Astronomy, University of Potsdam , 14476 Potsdam-Golm, GermanyInstitute for Physics & Astronomy, University of Potsdam , 14476 Potsdam-Golm, Germany; Department of Physics, Tampere University of Technology , 33101 Tampere, FinlandWe examine by extensive computer simulations the self-diffusion of anisotropic star-like particles in crowded two-dimensional solutions. We investigate the implications of the area coverage fraction ϕ of the crowders and the crowder–crowder adhesion properties on the regime of transient anomalous diffusion. We systematically compute the mean squared displacement (MSD) of the particles, their time averaged MSD, and the effective diffusion coefficient. The diffusion is ergodic in the limit of long traces, such that the mean time averaged MSD converges towards the ensemble averaged MSD, and features a small residual amplitude spread of the time averaged MSD from individual trajectories. At intermediate time scales, we quantify the anomalous diffusion in the system. Also, we show that the translational—but not rotational—diffusivity of the particles D is a nonmonotonic function of the attraction strength between them. Both diffusion coefficients decrease as the power law $D(\phi )\sim {(1-\phi /{\phi }^{\star })}^{2...2.4}$ with the area fraction ϕ occupied by the crowders and the critical value ${\phi }^{\star }.$ Our results might be applicable to rationalising the experimental observations of non-Brownian diffusion for a number of standard macromolecular crowders used in vitro to mimic the cytoplasmic conditions of living cells.https://doi.org/10.1088/1367-2630/17/11/113028anomalous diffusioncrowded fluidsstochastic processes |
| spellingShingle | Jaeoh Shin Andrey G Cherstvy Ralf Metzler Self-subdiffusion in solutions of star-shaped crowders: non-monotonic effects of inter-particle interactions New Journal of Physics anomalous diffusion crowded fluids stochastic processes |
| title | Self-subdiffusion in solutions of star-shaped crowders: non-monotonic effects of inter-particle interactions |
| title_full | Self-subdiffusion in solutions of star-shaped crowders: non-monotonic effects of inter-particle interactions |
| title_fullStr | Self-subdiffusion in solutions of star-shaped crowders: non-monotonic effects of inter-particle interactions |
| title_full_unstemmed | Self-subdiffusion in solutions of star-shaped crowders: non-monotonic effects of inter-particle interactions |
| title_short | Self-subdiffusion in solutions of star-shaped crowders: non-monotonic effects of inter-particle interactions |
| title_sort | self subdiffusion in solutions of star shaped crowders non monotonic effects of inter particle interactions |
| topic | anomalous diffusion crowded fluids stochastic processes |
| url | https://doi.org/10.1088/1367-2630/17/11/113028 |
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