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Evaluation of Blob Theory for the Diffusion of DNA in Nanochannels.

ABSTRACT: We have measured the diffusivity of ?-DNA molecules in approximately square nanochannels with effective sizes ranging from 117 nm to 260 nm at moderate ionic strength. The experimental results do not agree with the non-draining scaling predicted by blob theory. Rather, the data are consistent with the predictions of previous simulations of the Kirkwood diffusivity of a discrete wormlike chain model, without the need for any fitting parameters.

SUBMITTER: Gupta D

PROVIDER: S-EPMC5868977 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Evaluation of Blob Theory for the Diffusion of DNA in Nanochannels.

Gupta Damini D Bhandari Aditya Bikram AB Dorfman Kevin D KD

Macromolecules 20180220 5

We have measured the diffusivity of λ-DNA molecules in approximately square nanochannels with effective sizes ranging from 117 nm to 260 nm at moderate ionic strength. The experimental results do not agree with the non-draining scaling predicted by blob theory. Rather, the data are consistent with the predictions of previous simulations of the Kirkwood diffusivity of a discrete wormlike chain model, without the need for any fitting parameters. ...[more]

PMID: 29599567

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