The nanochannel delivery system (nDS) allows control over infusion rate, a boon for therapies designed to be delivered in regularly timed bursts. Chronobiology studies have also shown that hormone fluctuation in the body over the course of the day makes some drugs more effective when they can be delivered at specific times, such as dawn or sunset.
The system also allows doctors to stop or start drug delivery quickly and remotely in response to changes in patient health.
Delivery in space
The nDS device is the work of Texan biotech NanoMedical Systems and the Houston Methodist Research Institute (HMRI). The five-year project cost $1.92m (€1.5m), mostly granted by the Kennedy Space Center, part of the Center for the Advancement of Science in Space (CASIS).
"The prospect of developing and demonstrating a remotely controlled drug delivery implant excites us," said the head of the project at HMRI’s Department of Nanomedicine, Alessandro Grattoni. "If we are able to show the technology works in vivo and is safe, it could have an enormous impact on drug delivery and patient care."
As well as testing the limits of telemedicine, scientists chose to trial the device in space to model bone and muscle wastage. "Here the device will provide an agile means for controlling drug release where animal handling is extremely limited," said Grattoni. "Also, in microgravity, it will be possible to study the device in rapid and spontaneous models of osteoporosis and muscle atrophy."
If the technology proves successful, CASIS plans to use it to help other studies at the international space station. The team said it imagines other applications, “such as military emergency care, pre-clinical studies of newly discovered drugs, and care for astronauts on long space missions."
The delivery device is an 18mm-wide (two-thirds of an inch) cylinder with a reservoir for drugs and a silicon membrane housing 615,342 channels for drug release. These channels, some as small as 2.5nm, use nanotechnology to tune the rate of drug delivery using surface electrodes.
Using a radio-frequency remote control, the electrodes (and a battery below the drug reservoir) can be activated to influence the rate drugs seep through the porous membrane.
Grattoni said currently available drug infusion tech – external pumps, polymer implants that erode in the body, and implantable metal-gated devices – are limited because they can risk infections, are not adjustable once implanted, or have limited drug storage capacity.