There could be hope for diabetics who are tired of giving themselves insulin injections on a daily basis. Researchers at North Carolina State University and the University of North Carolina at Chapel Hill are developing a system in which a single injection of nanoparticles could deliver insulin internally for days at a time – with a little help from pulses of ultrasound.
The biocompatible and biodegradable nanoparticles are made of poly(lactic-co-glycolic acid), and contain a payload of insulin. Each particle has either a positively-charged chitosan coating, or a negatively-charged alginate coating. When the two types of particles are mixed together, these oppositely-charged coatings cause them to be drawn to each other by electrostatic force.