CONTROLLED-RELEASE DOSAGE FORM OF IBUPROF EN WHICH WAS LAYERED BY TALC WITH ETHYLCELLULOSE BINDER - II - INFLUENCE OF SCALE-UP

In this study we examined the influence of scale-up of the controlled- release dosage form of ibuprofen (IB), which was layered by talc using an ethylcellulose (EC) binder. We found that the rate of release of I B was markedly delayed by the scale-up. The mean pore size of the talc layer prepared by an experimental centrifugal fluidizing granulator w as 0.6 mu m, while that prepared by an industrial centrifugal fluidizi ng granulator was 0.16 mu m. The mean pore size of the talc layer was not influenced by the amount of the layered talc. It was previously re ported that the identification of granules could be expressed by the e fficiency of frictional wear. We, therefore, examined a correlation be tween the rate of release of IB and the efficiency of frictional wear. A. good correlation was found between them. These findings suggested that the amount of the layered talc and the efficiency of frictional w ear determined the rate of release of IB.