Fig. 3.

Normalized plateau modulus, $G_p^{\prime }\left(\gamma \right)/G_p^{\prime }\left({\gamma }_o\right)$, of DNAns networks as a function of strain, $\gamma$, in the elastic plateau regime ($\omega =63$ rad/s, T = 20°C) for $f=3$ (orange triangles) and 4 (blue diamonds) at [DNAns] of $\left(500\pm 10\right)$ and $\left(490\pm 10\right)$ $\mathrm{\mu }$M, respectively. Solid lines are fits of $\exp \left[{\left(\gamma /\gamma *\right)}^2\right]$ for ($\gamma \le {\gamma }_m$), where ${\gamma }_m$ (vertical dash-dot line) is the strain that maximizes $G_p^{\prime }$ and $\gamma *$ is the characteristic strain scale for stiffening. (Inset) Same plots for $f=5$ at [DNAns] of $\left(300\pm 10\right)$ $\mathrm{\mu }$M (light green) and $\left(550\pm 30\right)$ $\mathrm{\mu }$M (dark green) and for $f=6$ at [DNAns] of $\left(350\pm 20\right)$ $\mathrm{\mu }$M (pink) and $\left(550\pm 30\right)$ $\mathrm{\mu }$M (dark red). The solid black line denotes $\exp \left({\left(\gamma /1.1\right)}^2\right)$, which captures the nonlinear elasticity of the two lower-concentration $f=5$ and $f=6$ networks.