Abstract
The aim of the present study is to develop and evaluate gastro-retentive floating beads and floating in situ gels of griseofulvin (GF) in order enhance the dissolution rate and the bioavailability of GF. Different formulae of GF floating beads and floating in situ gels were prepared using sodium alginate, hydroxypropylmethyl cellulose (HPMC), carbopol, xanthan gum and pectin as polymers. The prepared formulae were evaluated for their physiochemical properties including the drug encapsulation efficiency, particle size, morphology, swelling, floating, density, gelation and viscosity behavior. Furthermore, the in vitro release pattern was examined. The results indicated that for GF floating beads; as the concentration of polymer increased, the encapsulation efficiency, particle size and floating lag time were increased. Swelling study showed that all GF floating formulae remained intact during the time of the experiment in buffered solution (pH, 1.2). Floating beads containing pectin showed rapid swelling rate, while the beads prepared with HPMC showed slower rate of swelling. For the floating in situ gels the results revealed that floating duration was more than 24 hours and all prepared floating in situ gels shown a decrease in viscosity with the increase in the shear rate. It was also found that the release rate of GF from all floating beads and floating in situ gels was significantly higher than its release from powder.