2002 Volume 62 Issue 2 Pages 67-79
Pressure swing granulation is a novel fluidized bed granulation method for fine cohesive powders requiring no binders or other additives. In this study we applied the pressure swing granulation for the first time to the granulation of pharmaceutical powders. The preparation of theophylline (TP) granules by the pressure swing granulation method was attempted, and the effects of granulation conditions on the granule properties were investigated. The utility of the TP granules as dry powder inhaler (DPI) was studied. It was feasible to granulate the TP particles using no binders by the pressure swing method. The granulation process varied, depending on granulation conditions, causing a change in the hardness of granules. The amount of TP remaining in a capsule at the inhalation study of the TP granules was greatly decreased compared with the TP powder. In the granule with lower hardness, the deposition percent of TP to respirable fraction increased. These results show that it is feasible to produce the DPI granules by the pressure swing granulation method, and the utility of the DPI can be raised by using the granule of low hardness.
