Polyelectrolyte Coated Multilayered Liposomes (Nanocapsules) for the Treatment of Helicobacter pylori Infection

Abstract
Helicobacter pylori infection is one of the major causes of gastric cancers. A number of systems have already been reported, but 100% eradication has never been achieved. The present invention designs a gastro-retentive drug delivery system incorporated with amoxicillin and metronidazole, specifically suited for the eradication of Helicobacter pylori infections due to its mucoadhesiveness in the presence of polyelectrolyte polymers. The system possesses the advantages of both vesicular and particulate carriers, and it was prepared by alternative coating of polyanion (poly(acrylic acid), PAA) and polycation (poly(allylamine hydrochloride), PAH) using liposomes as the core. Compared with the conventional liposomes, the polyelectrolyte based multilayered system (nanocapsules) gave prolonged drug release in simulated gastric fluid, which is well suited for drug delivery against H. pylori infection in the stomach. In vitro growth inhibition study, agglutination assay, and in situ adherence assay in cultured H. pylori suggested the successful in vitro activity and binding propensity of the system. In vivo bacterial clearance study carried out in a H. pylori infected mouse model finally confirmed the success of the developed novel nanocapsule system. Thus, the newly developed composite nanocapsules along with the use of combination therapy proved to have commendable potential in Helicobacter pylori eradication as compared to already existing conventional and novel drug delivery systems.