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Crowding-facilitated macromolecular transport in attractive micropost arrays.

ABSTRACT: Our study of DNA dynamics in weakly attractive nanofabricated post arrays revealed crowding enhances polymer transport, contrary to hindered transport in repulsive medium. The coupling of DNA diffusion and adsorption to the microposts results in more frequent cross-post hopping and increased long-term diffusivity with increased crowding density. We performed Langevin dynamics simulations and found maximum long-term diffusivity in post arrays with gap sizes comparable to the polymer radius of gyration. We found that macromolecular transport in weakly attractive post arrays is faster than in non-attractive dense medium. Furthermore, we employed hidden Markov analysis to determine the transition of macromolecular adsorption-desorption on posts and hopping between posts. The apparent free energy barriers are comparable to theoretical estimates determined from polymer conformational fluctuations.

SUBMITTER: Chien FT

PROVIDER: S-EPMC5430964 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Crowding-facilitated macromolecular transport in attractive micropost arrays.

Chien Fan-Tso FT Lin Po-Keng PK Chien Wei W Hung Cheng-Hsiang CH Yu Ming-Hung MH Chou Chia-Fu CF Chen Yeng-Long YL

Scientific reports 20170502 1

Our study of DNA dynamics in weakly attractive nanofabricated post arrays revealed crowding enhances polymer transport, contrary to hindered transport in repulsive medium. The coupling of DNA diffusion and adsorption to the microposts results in more frequent cross-post hopping and increased long-term diffusivity with increased crowding density. We performed Langevin dynamics simulations and found maximum long-term diffusivity in post arrays with gap sizes comparable to the polymer radius of gyr ...[more]

PMID: 28465594

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