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arXiv · 1211.3031

Directed translocation of a flexible polymer through a cone-shaped channel

Narges Nikoofard·Hamidreza Khalilian·Hossein Fazli
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Abstract

Entropy-driven directed translocation of a flexible polymer through a cone-shaped channel is studied theoretically and using computer simulation. For a given length of the channel, the effective force of entropic origin acting on the polymer is calculated as a function of the apex angle of the channel. It is found that the translocation time is a non-monotonic function of the apex angle. By increasing the apex angle from zero, the translocation time shows a minimum and then a maximum. Also, it is found that regardless of the value of the apex angle, the translocation time is a uniformly decreasing function of the channel length. The results of the theory and the simulation are in good qualitative agreement.

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Narges Nikoofard, Hamidreza Khalilian, Hossein Fazli. 2012-11-13. Directed translocation of a flexible polymer through a cone-shaped channel. https://doi.org/10.1063/1.4818419

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