Diffusion of self-propelled Janus tracer in polymeric environment

Nairhita Samanta; Rohit Goswami; Rajarshi Chakrabarti

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arXiv · 1704.06207

Diffusion of self-propelled Janus tracer in polymeric environment

Nairhita Samanta·Rohit Goswami·Rajarshi Chakrabarti

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Abstract

Artificially synthesized Janus particles have tremendous prospective as in-vivo drug-delivery agents due to the possibility of self-propulsion by external stimuli. Here we report the first ever computational study of translational and rotational motion of self-propelled Janus tracers in a het- erogeneous polymeric environment. The presence of polymers makes the translational mean square displacement (MSD) of the Janus tracer to grow very slowly as compared to that of a free Janus tracer, but surprisingly the mean square angular displacement (MSAD) is significantly increased as observed in a recent experiment. Moreover, with the increasing propulsion velocity, MSAD grows even faster. However, when the repulsive polymers are replaced with polymers with sticky zones, MSD and MSAD both show sharp decline.

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Nairhita Samanta, Rohit Goswami, Rajarshi Chakrabarti. 2017-04-20. Diffusion of self-propelled Janus tracer in polymeric environment. https://arxiv.org/abs/1704.06207

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