Chitosan-based drug nanocarriers: where do we stand?

Chitosan-based nanocarriers have become one of the most intensively studied transmucosal nanometric drug delivery platforms. This is due to a number of factors, including their simple and mild preparation technique as well as their capacity to associate macromolecules and facilitate their transport across mucosal barriers. In this review, we first describe our contribution to the origin of chitosan nanocarriers in the mid 90s, and summarize the early work that has impacted the development of this delivery technology. Secondly, we present our perspective regarding the potential of chitosan nanocarriers for some relevant applications: (i) vaccination, (ii) transmucosal protein delivery and (iii) gene therapy. Finally, we offer our perspective on the plausible advances in this area in the near future.