ACS Nano 12, 10957–10967 (2018)

Regenerative medicine approaches to treat spinal cord injuries (SCI) rely on engineered biomaterials that aim to reproduce the conductivity and mechanical properties of the native tissue, while promoting nerve regeneration. Various soft conductive hydrogels have been fabricated to this aim, but most are composed of a mesh of conductive polymers embedded in non-conductive hydrogels. This results in sub-optimal conductivity and risk of component leaching on swelling under physiological conditions.

Now Zhou et al. synthesize a highly conductive microporous soft hydrogel made of polypyrrole cross-linked and doped with tannic acid. When implanted in a mouse model of SCI, the material easily adheres to spinal cord tissue, restoring the interrupted electric signals in the area of a lesion and promoting neurogenesis. Cell infiltration in the micropores of the hydrogel contributes to tissue regeneration, and the anti-inflammatory characteristics of tannic acid prevent inflammation. Animals implanted with the conductive hydrogel display improved recovery of motor skills over the course of 6 weeks.