University of Otago, New Zealand


Te Tari Hua-Ruanuku

Supramolecular and Polymer group

Medical Gels

Our chitosan-dextran gel has proved itself to be a real winner, and has just been licensed to Medtronic for ENT applications. It stops bleeding, infection, and dramatically reduces adhesions. The two pot mixture sets within a minute to form a firm gel that slowly is degraded in the body. We are currently looking into the biochemistry of the gel. In another project, we are developing tough glues for surgery and skin repairs.

The Chemistry:

The gel is in two parts. The first is a succinylated chitosan which is soluble at neutral pH. The second component is an oxidized dextran containing aldehyde groups, which provides for cross-linking and appears to be the main biochemically active component.


The gel has shown useful bioactivity. For instance, it is active against a wide range of bacterial, attacking the cell wall. In addition it shows mild temporary suppression of fibroblasts, which may be the key to its anti-adhesion effect.

healthy e-coli
healthy E Coli

E Coli after exposure to dextran aldehyde
E Coli after exposure to dextran aldehyde