Erratum: “Distribution of distances between DNA barcode labels in nanochannels close to the persistence length” [J. Chem. Phys. 142, 064902 (2015)]

On page 7 of our manuscript,¹ we state an ionic strength of 24 mM based on TBE 0.5×. This estimate of the ionic strength does not include the residual salts from the nick labeling and repair reactions, which leads to an ionic strength of 103 mM.

The following items in our manuscript are affected by the change in the reported ionic strength:

• 1.On page 7, the text “To estimate $\xi$ for our experiments, we use D_eff = 40 nm as a representative channel size. The persistence length l_p = 58 nm and effective width $w=10$ nm were estimated from Dobrynin’s theory⁴⁰ and Stigter’s theory,⁴¹ respectively, in TBE 0.5× buffer ($I\approx 2.4\times 10^{-2}$ M). For the global persistence length, we take advantage of a recent calculation²² indicating that g = 190 nm for this value of $D_{\mathrm{\text{eff}}}∕l_p$. As a result, the experiments described here correspond to $\xi =47.7$. Repeating the calculation leads to $\xi$ = 47.7, 30.6, 24.9, 8.7, and 6.5 for the five different channels (in increasing order).” is replaced by “To estimate $\xi$ for our experiments, we use D_eff = 34.4 nm as a representative channel size. The persistence length l_p = 52 nm and effective width $w=5.6$ nm were estimated from Dobrynin’s theory⁴⁰ and Stigter’s theory,⁴¹ respectively, in TBE 0.5× buffer with the additional salts from the nick label and repair steps ($I\approx 103$ mM). For the global persistence length, we take advantage of a recent calculation²² indicating that g = 1455 nm for this value of $D_{\mathrm{\text{eff}}}∕l_p$. As a result, the experiments described here correspond to $\xi =5.95$. Repeating the calculation leads to $\xi$ = 5.95, 4.26, 3.64, 1.60, and 1.27 for the five different channels (in increasing order).”
• 2.In Sec. IV B, the statement “To make this comparison, we used the values of l_p = 58 nm and $w=10$ nm cited above.” is replaced by “To make this comparison, we used the values of l_p = 52 nm and $w=5.6$ nm cited above.”
• 3.Figure 9 of the original manuscript¹ is replaced with Fig. 1 of this erratum, and Fig. 10 of the original manuscript¹ is replaced with Fig. 2 of this erratum.

FIG. 1.

Comparison of experimental data (blue squares), the harmonic approximation (green circles, see Sec. IV C), and Odijk’s theories. (a) Fractional extension, where the solid line is Eq. (10). (b) Variance, where the solid line is Eq. (12) and the dashed line is Eq. (13). The data points for the experimental data and the harmonic approximation are the average value obtained over all bins; the standard error is smaller than the data points.

FIG. 2.

Comparison of (a) the average extension and (b) the variance about the average extension for a harmonic approximation about the minimum free energy (black squares) and the experimental data (blue circles). These data correspond to the 43 nm channel. Note that (b) is a log-log plot, so the deviation between the model and experimental data is larger than that in the linear plot of (a). Similar plots for the other channel sizes are included as the supplementary material.

These corrected figures and calculations of the Odijk parameter $\xi$ are quantitatively different than the original manuscript, but the conclusions drawn from the analysis are unchanged.

See supplementary material for corrected versions of Figs. 7 and 8 of the original manuscript.¹