Silica-Chitosan Peptic Ulcer Treatment

ISTN is currently developing a composite drug delivery system for treating peptic ulcers that is made by encapsulating the biopolymer chitosan with surface-modified silica nanoparticles. In addition to being biocompatible and biodegradable, chitosan is highly suitable to drug delivery because of its permeation enhancement, mucoadhesiveness and ability to perform sustained controlled release. Because silica gel is very stable in acid, a silica-chitosan nanocomposite would significantly retard leaching in acidic environments. Therefore, in the gastric environment, this composite would control the drug release rate more effectively than chitosan could on a standalone basis.

This new drug-carrying material would be ingested into the stomach where the mucoadhesive properties of the chitosan would allow it to attach itself to the stomach lining. The acidic environment of the stomach would then cause the chitosan to swell, releasing the drug. This system would provide a more direct delivery of antibiotics to combat the H. Pylori bacteria, which has been shown to be the major cause of stomach ulcers. By delivering antibiotics directly to the stomach lining there would be an increase in the effectiveness over other treatments, which rely on the drug being diffused throughout the stomach.

In addition to peptic ulcer treatment, a silica-chitosan nanocomposite also has the potential to be utilized for the non-invasive administration of therapeutic peptides. The choice of the appropriate colloidal gel system could create enabling technologies for implants, nasal sprays and other delivery methods that require blood compatibility.