Abstract
A novel gastro-mucoadhesive delivery system based on a kind of anion ion-exchange fiber has been developed. Furosemide (FM), which is site-specifically absorbed from the upper gastrointestinal (GI) tract, was used as model drug. A novel-modified dissolution system, which can also be called “flow through diffusion cell,” was used to study the drug release from the drug fibers. The GI transit studies of the FM fiber complexes in rats and gamma imaging studies in volunteers were carried out to evaluate the gastro-mucoadhesive behavior of the fiber. The pharmacokinetic profile and parameters of the FM suspension and FM fiber in fasted and fed rats were measured, respectively. Studies on rats and volunteers provided evidence for the validity of the hypothesis that the drug fiber provided better gastro-mucoadhesive properties in vivo.