Insulin is a hormone controlling the metabolism of glucose and fat. When this hormone is lacking or the body does not respond to it, a severe disease known as diabetes develops. Although regular insulin injections can control the glucose levels in diabetic patients, this therapy is often associated with pain and microbial infections.

To overcome these limitations, Jin Di, University of North Carolina, Chapel Hill, and North Carolina State University, Raleigh, NC, USA, developed a novel insulin-delivery system. The researchers mixed together nanoparticles coated with cationic polysaccharide chitosan and those coated with anionic polysaccharide alginate. In this way, the scientists obtained a three-dimensional gel-like nano-network able to encapsulate insulin.

This nanostructure works as a biocompatible insulin arsenal because it can be retained underneath the skin and it dissociates upon stimulation with ultrasound, thereby releasing insulin. As a consequence, this new insulin-delivery system efficiently regulated blood glucose levels in diabetic mice.

• Ultrasound-Triggered Regulation of Blood Glucose Levels Using Injectable Nano-Network
  Advanced Healthcare Materials,
  Jin Di, Jennifer Price, Xiao Gu, Xiaoning Jiang, Yun Jing, Zhen Gu,
  Adv. Healthcare Mater. 2013
  DOI: 10.1002/adhm.201300490