Floating microspheres bearing acetohydroxamic acid for the treatment of Helicobacter pylori.

This investigation is part of our ongoing effort to develop effective drug delivery systems for the treatment of Helicobacter pylori infection using polycarbonate (PC) floating microspheres as drug carriers. In an effort to augment the anti-H. pylori effect of acetohydroxamic acid (AHA), floating PC microspheres, which have the ability to reside in the gastrointestinal (GI) tract for an extended period, were prepared by emulsion (O/W) solvent evaporation technique. The effect of PC concentration on the morphology, particle size, entrapment efficiency and drug release rate was studied. In-vitro studies confirmed the excellent floating properties of PC microspheres. In-vitro and in-vivo growth inhibition studies were performed on developed system(s) taking isolated cultures of H. pylori and H. pylori-infected Mongolian gerbils, respectively. The drug and PC microspheres both showed anti-H. pylori activity in vivo, but the required dose of AHA was effectively reduced by a factor of 10 in the case of PC microspheres. In conclusion, the floating microspheres more effectively cleared H. pylori from the GI tract than the drug because of the prolonged gastric residence time resulting from the excellent buoyancy of the PC.