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 sizes ranging from 305 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 ∼ 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. (Figure Presented).
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© 2015 American Chemical Society.