Figure 2.
The digital camera image displays the formation of a three-dimensional polymer layer on a cylindrical core hydrogel substrate (substrate dimensions: 4mm diameter, 4.8 cm height). A 15wt% PEGDA575, 0.04wt% fluorescein-acrylate core hydrogel substrate, swollen with 2.5 X 10−2 M glucose, (shown in yellow) was partially immersed into a precursor solution containing 3.1 X 10−6 M GOX, 2.5 X 10−4 M Fe+2, 10mM MES pH=4.5, 0.005wt% rhodamine-B acrylate, 15wt% PEGDA700 for 60 seconds. The uniform three-dimensional intact coating (shown in red) remained attached to the hydrogel after agitation in water for 24 hours and incubation in water for 16 weeks.