Wire-templated electrodeposition of vessel-like structured chitosan hydrogel by using a pulsed electrical signal

Herein, by performing the templated electrodepsotion process with the oscillating electrical signal stimulation, a vessel-like structured chitosan hydrogel (diameter about 0.4 mm) was successfully prepared in the absence of salt condition. Experimental results demonstrated that the hydrogel growth (e.g. thickness) is linearly correlated to the imposed charge transfer and can be well quantified by using a theoretical moving front model. Morpgological observations indicated the heterogeneous multilayer structure was spatially and temporally controlled by an externally employed electrical signal sequence while the channel structure could be determined by the shaped electrode. Moreover, the oscillating ON/OFF cycles were proved to strongly affect the film structure, leading to a more compact hydrogel coating with lower water content, higher crystallinity, complex layer architecture and relative strong mechanical property that can be facilely peeled off as a free-standing hollow tube. Importantly, all the experiments were conducted under sorts and mild of conditions that allowed the additional enhancing materials to be added in to further improve the mechanical and/or biological properties. Thus, this work spurs a very promising self-assembly technology for the multi-functional hydrogel coating construction and artificial blood vessel regeneration.