Floating in situ gelling system of acetohydroxamic acid for clearance of H. pylori

The objective of this study was to develop a novel floating in situ gel system for sustained drug delivery of acetohydroxamic acid (FIGA) for eradication of Helicobacter pylori (H. pylori). The FIGA was prepared by dissolving the different concentration of gellan in deionized water at 80 degrees C. Different concentration of drug and calcium carbonate as floating agents were dispersed with stirring. In vitro results revealed that in situ gelling formulation forms rigid gels instantaneously and floated for longed period time of time in SGF pH 1.2. The formulation parameters, such as concentration of polymer, concentration of calcium carbonate, and concentration of drug, affected the in vitro drug release characteristic significantly. Absence of drug-polymer interaction was confirmed by differential scanning calorimetry analysis. The in vivo H. pylori clearance efficacy of prepared FIGA in reference to acetohydroxamic acid suspension following repeated oral administration to H. pylori-infected Mongolian gerbils was examined by microbial culture method. FIGA showed a significant anti-H. pylori effect in the in vivo gerbil model. It was noted that the required amount of acetohydroxamic acid for eradication of H. pylori was very less in FIGA than in the corresponding acetohydroxamic acid suspension. From the above results, it was concluded that the floating in situ gelling system has feasibility for forming rigid gels in the stomach and eradicated H. pylori from the gastrointestinal tract more effectively than acetohydroxamic acid suspension because of the prolonged gastrointestinal residence time of the formulation.