Formulation and invitro evaluation of buoyant drug delivery system of Glipizide using acrylic polymer

Recently, several technical advancements have led to the development of several novel drug delivery systems (NDDS) that could release the active ingredient over an extended period of time and further deliver the drug directly to the site of action, thus minimizing or eliminating side effects. In the present study8 formulations of Glipizide floating microspheres were prepared using varying concentrations of Eudragit RS100 and HPMC by Emulsification solvent diffusion method. The floating microspheres were evaluated for percentage yield, drug loading,in-vitrobuoyancy behavior as well as drug polymer compatibility, scanning electron microscopy, and in-vitro drug release. The micrometric properties were found to be good and scanning electron microscopy shows that the microspheres were spherical with smooth surface and a hallow cavity inside microspheres. The practical yield was found to be in the range of 69.88-95.98% and with a particle size range of 617.19-882.75 μm. The percent entrapment is about 60.24% to 90.68% and percent drug loading is about 18.21 to 30.85% which decreased with increase in HPMC concentration in the formulations. The microspheres with high concentrations of Eudragit showed higher buoyancy. The in-vitrorelease was slow and extended to more than 12 hours which increased with significant increasein HPMC concentration but decreased in buoyancy character. Release obeys zero order kinetics and the drug release was diffusion controlled. Hence it can be concluded that the floating microsphere of Glipizide may prolong drug release thereby improving bioavailability and enhance opportunity of absorption in stomach