Terminator-style liquid metal connects severed nerves

Hasta la vista, nerve damage. Experiments with bullfrog nerves show that a Terminator-style liquid metal alloy could one day be placed in the body to help severed nerves reconnect.

The alloy would stay in place until the nerve has healed, before being slurped back out with a syringe.

The peripheral nervous system consists of nerves that carry electrical signals from the brain to the rest of the body. Because they aren't protected by the spine or the skull, peripheral nerves are more vulnerable to injuries than those in the central nervous system.

Severed nerves can reconnect if treated quickly enough, but at a rate of just 1 millimetre per day. Also, existing methods for grafting nerve ends back together have serious shortcomings. For instance, most existing scaffolds for grafts must ultimately be removed, requiring risky follow-up surgery. Even more worrisome, if the nerves don't pass signals to muscles during the healing process, the muscles can atrophy to the point where they never fully recover.

"Taking the functional recovery into consideration during the regeneration is of great significance for patients," says Jing Liu at Tsinghua University in Beijing, China.

Liu and his colleagues wondered if liquid metal could act as a backup system for damaged nerves, helping signals pass through a graft while the nerve healed. They used an alloy of gallium, indium and selenium, which is a very good electrical conductor. The alloy is liquid at room temperature, allowing it to be removed with a syringe when it's no longer needed.