Formulation and Evaluation of Floating Microcapsules of Cefpodoxime Proxetil

Introduction: Floating drug delivery system is widely used technique to obtain higher bioavailability for drugs which have an absorption window in the stomach. Floating microcapsule is one approach to improve gastroretention for oral sustained release dosage forms. Cefpodoxime Proxetil has a biological half life of 2.5 h and is degraded at higher pH. Objective: Aim of this study was to develop floating microcapsules of Cefpodoxime Proxetil by solvent evaporation technique using Eudragit S100 as a release retarding material. Experimental: A 32 full factorial design was employed to investigate the relationship between concentration of Eudragit and stirring speed on percent release at 12 h, percent entrapment efficiency and particle size. The microcapsules were also characterized for drug content, percentage yield, floatability and surface morphology. Results: The particle size of all batches was found to be in the range of 150-290 μm. Increase in concentration of Eudragit S100 was found to increase the entrapment efficiency and mean particle size of the microcapsules. The percent release was found to be higher for microcapsules prepared at higher stirring speed which could be due to lower particle size of microcapsules and hence reduced diffusional path length. All batches of microcapsules remained buoyant for 12 h. It was observed that increasing the polymer concentration caused a decrease in the rate of drug release. The optimum formulation was subjected to pharmacokinetic studies. In vivo studies revealed a 1.6 fold increase in relative bioavailability of Cefpodoxime Proxetil as microcapsules.