Fig. 2.

Detachment of hydrogel structures from ITO electrodes. (A) SEM micrograph showing heparin-based hydrogel structures patterned on top of ITO electrodes. (B) Applying reductive potential (−1.8 V for 60 s) to selected electrodes resulted in detachment of hydrogel elements while hydrogel on unactivated electrode (bottom right) remained attached. (C) Ferricyanide cyclic voltammetry was used to verify the assembly and desorption of silane molecules and hydrogel elements. The redox peaks shown with bare ITO electrode disappeared upon silane modification and hydrogel patterning, but reappeared after electrical stimulation of an electrode. The resumption of interfacial electron transfer pointed to removal of the hydrogel/silane layer.