Thesis (M.Sc.)--Chulalongkorn University, 2007

This work focused on the development of gastroretentive dosage forms of amoxicillin using alginate and gelatin as a matrix polymers and chitosan as a mucoadhesive polymer coating for the effective eradication of Helicobacter Pylori, a major causative agent of peptic ulcer. In all cases, an incorporation of gelatin in the alginate matrix presented only minor effect to the beads properties. The amoxicillin-loaded alginate beads coated with 0.5% (w/v) chitosan (ALG/0.5%CHI) showed the excellent floating ability as well as the in vitro mucoadhesive test. The beads were able to adhere strongly to the gastric mucosal layer. The in vitro release profiles revealed that amoxicillin released faster in pH 1.2 hydrochloric acid (HCl) than in pH 7.4 phosphate buffer. However, the result showed that ALG/0.5%CHI was able to sustain the release of amoxicillin for over 6 hours in the simulated gastric fluid (pH 1.2 HCl). In summary, it can be concluded that amoxicillin-loaded alginate beads coated with 0.5% (w/v) chitosan offer a novel alternative for the effective treatment of peptic ulcer.