WASHINGTON — Injuries which damage your nerves can have lasting repercussions. Patients often deal with chronic pain, develop neurologic disorders, or even experience paralysis after their ordeal. While nerve transplants can sometimes work, they don’t always get the job done. Now, scientists have developed a new material which they say can help the body heal and recover nerve function.
Hydrogel is a water-swollen polymer which is compatible with the human body and can transmit bioelectrical signals. Researchers from Nanjing University in China say their new version of hydrogel is both stretchable and conductive, allowing surgeons to one day use this material in operations on injured patients.
The study focuses on peripheral nerves, which are nerve tissues that send electrical signals between the brain and the rest of the body. This system contains 43 pairs of motor and sensory nerves, controlling sensation, movement, and motor coordination. While they are vitally important, they are also extremely fragile and suffer damage easily.
Issues with surgery
In many accidents, peripheral nerves can be completely severed by deep cuts and other traumatic wounds. Researchers say the common strategy is to transplant other nerves which take the damaged one’s place. This procedure, an autologous nerve transplantation, takes a peripheral nerve from another part of the body and sews it to the ends of severed connections.
The problem with these operations is that a transplant doesn’t always restore the nerve function. Patients sometimes needs several follow-up surgeries to get the connections right. Artificial nerve grafts are also an option, but these products can take a long time to repair the damage as well.
Success with nerve damage in lab animals
To create a new solution, the Chinese team prepared a tough but stretchable hydrogel using polyaniline and polyacrylamide. Their polymer also had a 3D microporous network which allows nerve cells to enter the material and cling to it. The porous substance also helps the body restore lost tissue.
In the study, researchers showed that hydrogel can successfully send bioelectrical signals through the damaged sciatic nerve removed from a toad. The experiment also implants hydrogel into rats with sciatic nerve damage. After two weeks, the rats implanted with hydrogel recovered many of their bioelectrical signaling ability. This allowed them to walk better than rats without implants that are still dealing with nerve injuries.
“As hydrogels are more similar to nerve tissue, functional hydrogels have become a promising candidate for bioelectronics,” study authors write.
The study adds that irradiating this material with near-infrared light improves hydrogel’s ability to conduct electricity. Researchers believe this can further help patients regain nerve function since near-infrared light can penetrate tissues.
The study appears in the journal ACS Nano.