A hydrogel that could help repair damaged nerves

Injuries to peripheral nerves – tissues that transmit bioelectrical signals from the brain to the rest of the body – often result in chronic pain, neurologic disorders, paralysis or disability.

Now, researchers have developed a stretchable conductive hydrogel that could someday be used to repair these types of nerves when there's damage.

A common strategy, called autologous nerve transplantation, involves removing a section of peripheral nerve from elsewhere in the body and sewing it onto the ends of the severed one. However, the surgery does not always restore function, and multiple follow-up surgeries are sometimes needed. Artificial nerve grafts, in combination with supporting cells, have also been used, but it often takes a long time for nerves to fully recover.

Qun-Dong Shen, Chang-Chun Wang, Ze-Zhang Zhu and colleagues wanted to develop an effective, fast-acting treatment that could replace autologous nerve transplantation. For this purpose, they decided to explore conducting hydrogels – water-swollen, biocompatible polymers that can transmit bioelectrical signals.

The researchers prepared a tough but stretchable conductive hydrogel containing polyaniline and polyacrylamide. The crosslinked polymer had a 3-D microporous network that, once implanted, allowed nerve cells to enter and adhere, helping restore lost tissue.