Researchers at North Carolina State University and the University of North Carolina at Chapel Hill have are looking at nanoparticles and ultrasound as a way to do away with the need for daily injections of insulin via syringes and needles.
Instead, people with diabetes would be injected under the skin with ultra-small insulin-carrying nanoparticles. The porous particles leak insulin that forms a reservoir that is contained by the particles’ electrostatic properties. Until the insulin is needed, that electrostatic force prevents it from entering the bloodstream.
Then, when diabetes patients want an insulin dose, they use a small ultrasound-emitting device to weaken the electrostatic force and allow the insulin reservoir to enter the bloodstream. When the ultrasound is removed and the electrostatic force is restored, the nanoparticles resume seeping insulin and form a new reservoir.
In experiments with lab mice, a single injection of insulin-bearing nanoparticles provided 10 days worth of blood glucose control. Once the biodegradable nanoparticles are depleted, they are easily absorbed by the body.
Although the technology would not do away completely with the need for injections, it would reduce their frequency substantially, freeing insulin users from the drudgery and pain of daily, often multiple, injections by syringe or pen.
Next steps include testing this approach on human subjects and perfecting the ultrasound device in terms of size and reliability.
An abstract of the study is available at http://onlinelibrary.wiley.com/doi/10.1002/adhm.201300490/abstract.