FIGURE 5.

In vitro glucose detection on agarose hydrogel skin model. (A) Scheme of using grooved MNs for colorimetric glucose detection. (B) The required detection duration of the grooved MNs from 1% agarose hydrogel skin model containing different concentrations of glucose. (C) The colorimetric response of the grooved MN array on the skin phantom within 60 s application. The grooved MNs were tested on a series of agarose hydrogel containing glucose concentrations from 0.1, 0.25, 0.5, 1, to 2 wt%. The colors changes of glucose test strips in the solutions with the same glucose concentrations were compared with that obtained from grooved MNs. Scale bar = 5 mm