EFFECT OF BINDER LEVEL AND GRANULATING LIQUID ON PHENYLBUTAZONE PELLETS PREPARED BY EXTRUSION-SPHERONIZATION

The effects of type and amount of binding agent and different amounts of granulating liquid on the physical properties of uncoated beads of phenylbutazone were investigated. The binders used were polyvinylpyrro lidone (PVP) and gelatin/starch (G/S) at two levels, and each formulat ion at two percentages of granulating liquid; water/ethanol at 60/40 r atio. The ability of these binders to produce pellets of phenylbutazon e by the extrusion-spheronization method was evaluated by two criteria . The first was physical properties such as particle size, yield betwe en 710 and 1400 mu m, friability, and density. The other criterion was the drug release profile. Generally 5% of gelatin/starch with 80% of solvent produced more uniform pellets with a narrower particle size ra nge and a high yield of spheres between 710 and 1000 mu m. Changing th e type of the binder, its percentage, and the amount of granulating li quid had no significant effect on the pellet density. Changing the typ e of the binder or/and its percentage and also the effect of granulati ng liquid in combination with the other mentioned variables had signif icant effects on the friability of the pellets. The results show that the amount of granulating liquid and binder amount have the same influ ence on the drug release from pellets. A slower release rate was obser ved with increased amounts of these two variables. These differences i n the release profiles were parallel to the differences in hardness an d structure of the pellets. The difference between particle diameter a nd the percentage of drug released within 30 min was significant in al l formulations.