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Experimental evidence of weak excluded volume effects for nanochannel confined DNA.

ABSTRACT: We present experimental demonstration that weak excluded volume effects arise in DNA nanochannel confinement. In particular, by performing measurements of the variance in chain extension as a function of nanochannel dimension for effective channel size ranging from 305 nm to 453 nm, we show that the scaling of the variance in extension with channel size rejects the de Gennes scaling ?2X ~ D1/3 in favor of ?2X ~ D0 using uncertainty at the 95% confidence level. We also show how simulations and confinement spectroscopy can be combined to reduce molecular weight dispersity effects arising from shearing, photocleavage, and nonuniform staining of DNA.

SUBMITTER: Gupta D

PROVIDER: S-EPMC4671635 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Experimental evidence of weak excluded volume effects for nanochannel confined DNA.

Gupta Damini D Miller Jeremy J JJ Muralidhar Abhiram A Mahshid Sara S Reisner Walter W Dorfman Kevin D KD

ACS macro letters 20150702 7

We present experimental demonstration that weak excluded volume effects arise in DNA nanochannel confinement. In particular, by performing measurements of the variance in chain extension as a function of nanochannel dimension for effective channel size ranging from 305 nm to 453 nm, we show that the scaling of the variance in extension with channel size rejects the de Gennes scaling δ2X ~ D1/3 in favor of δ2X ~ D<s ...[more]

PMID: 26664782

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