Taiwanese researchers reported development of a nanoparticle drug delivery system that shows promise as a potential way to administer insulin by mouth rather than through injection, infusion or nasal sprays.

The scientists at the National Tsing Hua University, the Chinese Naval Academy and the National Health Research Institute point out that stomach acid and different digestive enzymes degrade insulin and other protein-based drugs, making them ineffective.

And if there was a way insulin taken orally could be protected from damage in the stomach, the challenge becomes how to get it through the epithelial barrier in the small intestine so it could be absorbed in the bloodstream.

In their research, published Jan. 8 in the American Chemical Society's monthly journal Biomacromolecules, the researchers said they loaded insulin into nanospheres made from chitosan, a natural carbohydrate polymer material obtained from shells of shrimp that is nontoxic and biocompatible.

When given to diabetic laboratory rats, the insulin-loaded nanoparticles seemed to make it through the stomach and into the bloodstream, successfully reducing blood sugar levels in the animals, the researchers reported.