There’s a dire need to find alternatives to opioids – the highly effective but highly addictive medications. And now local engineers are going directly to the source to stop the pain.

At a lab at Northwestern University, it’s all about tiny devices that make a big impact. From sensors that measure vital signs for babies in the neonatal intensive care unit to devices that track recovery in stroke patients, Professor John Rogers’ latest project is pain.

“Managing and treating pain is an important part of patient care,” Rogers said. “Drug-based approaches such as those that rely on opioids are spectacularly effective, but they have side effects including extreme levels of addiction.”

Instead of popping a pill, Rogers wants to implant this flexible strip.

“It’s an implantable device. It’s a soft rubbery device that gently envelops a targeted nerve,” he said. “It could be a nerve bundle it could be an individual nerve fiber.”

The devices – tested on the sciatic nerve in animal models — contain microfluid channels that deliver a cooling liquid directly to selected peripheral nerves. The coolant slows pain signals, eventually stopping them from traveling to the brain.

“There are a whole number of different processes that decrease and slow down when you reduce the temperature of the tissue and the net effect of that is the nerve signals can no longer propagate,” Rogers said.

An electrical conduction system, made onsite in the lab, controls the flow of coolant and measures temperature. Think of it like an on/off switch.

“You can dial in the magnitude of the pain relief that is being provided,” Rogers said. “So we think that is an important, powerful distinction between an engineering approach and a chemistry approach.”

Encased in flexible polymer, the device is designed to be implanted at the time of a surgery. It stays in the body for days to weeks then dissolves.

“It’s designed to naturally melt away and dissolve and disappear in the body much like a resorbable suture,” Rogers said. “Treating pain is such a challenging thing. It’s so essential to patient care. If we can kind of move the needle and add to the set of options physicians have around relieving pain. That could be a good way for us to contribute as engineers.”

The next step is to test the coolant for longer periods of time to determine how much is needed to be effective without damaging the nerve.