Figure 5.

(a) Reflectance from the GNR-hydrogel with smoothing function, in pH 4.5 with $R_{\lambda }\left(\mathrm{pH}4.5\right)$; (b) reflectance from the GNR-hydrogel in (1) pH 3.0 with $R_{\lambda }\left(\mathrm{pH}3.0\right)$ and $R_{\lambda }\left(\mathrm{pH}4.5\right)$ and (2) 40 wt % glycerol at pH 4.5 with $R_{\lambda }$ (40 wt % glycerol, pH 4.5) and $R_{\lambda }\left(\mathrm{pH}4.5\right)$.