A dissolving implantable device has vee developed to relieve pain without drugs. The new approach could provide an alternative to opioids and other highly addictive drugs.
The bioelectronic device, from a Northwestern University-led team, takes the form of a soft, flexible implant and it uses cooling, instead of drugs, to silence pain signals. The device is made up of an integrated sensor, which monitors temperature at the affected nerves. An advantage of the device is that when it is no longer needed, it is harmlessly absorbed by the body.
The biocompatible, water-soluble device functions by softly wrapping around nerves to deliver precise, targeted cooling, which numbs nerves and blocks pain signals to the brain. There is an element of user control, via an external pump. This allows the user to remotely activate the device and then increase or decrease its intensity. device is just 5 millimeters wide.
According to lead research John A. Rogers: “Although opioids are extremely effective, they also are extremely addictive. As engineers, we are motivated by the idea of treating pain without drugs — in ways that can be turned on and off instantly, with user control over the intensity of relief.”
At present the device has only been tested using animals, however the results are encouraging. In the animal study, the device successfully and reversibly blocked pain signals without side effects.
The developers hope the device will be useful for patients who undergo routine surgeries or traumatic events like amputations, as part of the post-operative medication regime. In these circumstances, surgeons would be able to implant the device during the procedure to manage the patient’s post-operative pain.
The basis of the device is evaporation. The device contains a liquid coolant that is induced to evaporate at the specific location of a sensory nerve. This is a similar concept to how sweat cools down the body during hot periods. With the device acting on the nerve, the signals that travel through the nerve become slower and slower and eventually the signals will stop completely.
The cooling effect can occur by delivering the signal to only one or two targeted nerves. By selecting specific nerves, different sites within the body can be targeted.
The device contains microfluidic channels. In one channel is a liquid coolant (perfluoropentane); in the second channel is nitrogen gas. As the liquid and gas flow into a shared chamber, a reaction occurs that causes the liquid to promptly evaporate.
The development of the device appears in the journal Science. The research paper is titled “Soft, bioresorbable coolers for reversible conduction block of peripheral nerves.”