Natural polymers vaccine delivery

However, being a natural polymer, chitosan has aU disadvantages of natural materials mentioned earlier (see Section 11. A). Presently, a lot of other polyplexes based on cationic synthetic polymers have been described in the literature. Among others, we could mention rather new DNA delivery nanoparticles based on poly(2-dimethylamino)ethyl methacrylate-co-poly(ethylene glycol) (PDMAEMA) [70,71] and PEGylated polyethylenimine (PEI/DNA) [72]. The last polyplexes have been encapsulated in PLGA microparticles and proposed for mucosal (oral) polyplex-based vaccination of Wistar rats. 

In order to establish the extent to which the native conformation of the protein is retained when in contact with functional silicones, proteins are entrapped within water-in-silicone oil emulsions and their biological activity assessed. The objective is to elucidate the nature of the interaction between the biological and synthetic polymers, the role of different polar groups on the silicones, the denaturation rate of the proteins in contact with the functionalised silicones, and the role of different polar groups on the silicone polymer. Through the use of modified silicones in conjunction with proteins at these water-oil interfaces, it may possible to increase the stability of not only the interface, but of the protein as well. The results presented, combined with the ability to entrap more than one protein in the emulsion droplets at time, offers a great potential for using these systems as delivery vehicles in oral vaccinations. 9 refs. 

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