Continuous electro-growth of a hierarchically structured hydrogel on a non-conductive surface

Abstract

Designing hydrogels with hierarchically ordered structures is of significance for biomimetic applications through simulating natural biological soft tissues. Due to the soft and fragile features of hydrogels, it is challenging to create complex structures that can be orientation-modulated in a facile and continuous manner. In this study, we developed a novel method to electro-assemble natural polymeric hydrogels on a non-conductive surface, eliminating the harsh pH changes near the electrode during electrodeposition. Under optimal circumstances, charged polymeric chains were packed densely in a continuous manner and aligned parallel to the non-conductive surface. The oriented hydrogels could be peeled off from the non-conductive surface, and they demonstrated excellent mechanical properties. We also found that electric field intensity had a profound effect on the microstructure of the hydrogel. By programming the electric signals, we could construct complex structured hydrogels with regulated orientation, which have potential applications in biomimetic material design.