FORMULATION, OPTIMIZATION & EVALUATION OF SOLID DISPERSION BASED GASTRORETENTIVE FLOATING TABLETS OF CEFPODOXIME PROXETIL

The objective of present study was to preclude of poor dissolution of relatively water insoluble and poorly permeable drug by formulating gastroretentive floating tablet using solid dispersion (SD) of the drug. It aimed to increase the drug solubility and gastric retention of the drug for better absorption profile. Cefpodoxime proxetil is an orally absorbed third generation cephalosporin antibiotic. The oral bioavailability and biological half life is 50% and 2.09 to 2.84 hrs respectively. Two grades of Polyethylene glycol (PEG); PEG 4000 and PEG 6000 in combination were used for the formulation of solid dispersion. Formulation batch SD8 was found to be optimized according to the face centred cube design (FCCD). Solubility and the drug release from batch SD8 was maximum in 0.1N HCL, 18.93mg/ml and 94.66% respectively as compared to physical mixtures (PM) and pure drug. The physical mixture having same carrier ratio (PEG 4000+PEG 6000) that is PM8 has solubility and drug release 13.93mg/ml and 76.34% respectively. The study showed that solubility and drug release has linear relationship with PEG concentration. The optimized batch of the SD was further used for the formulation of the gastroretentive floating tablets by using HPMC K15 M as the hydrophilic polymer and sodium bicarbonate as gas generating agent. The gastroretentive floating tablets was formulated by direct compression method and tested for various physicochemical parameters for tablets like tablet weight variation, thickness, hardness, friability, content uniformity, in vitro buoyancy studies, swelling index and in vitro drug release.