Computational determination of hydrodynamics in the USP dissolution testing Apparatus 1 (rotating basket)

The USP Apparatus 1 is a common analytical tool used to evaluate drug release profiles in pharmaceutical research and development and for formulation-predictive dissolution testing. Different basket mesh sizes can be selected to ensure the most discriminatory method between formulations. In this work the velocity distributions, strain rates, dissipation rates, and flow rates in the rotating basket (10- and 20-mesh) dissolution apparatus operating at 100 rpm in 900-mL liquid fill were predicted using Computational Fluid Dynamics (CFD). The predictions were compared with previous experimental results. In general, substantial agreement between the CFD predictions and the experimental PIV measurements was obtained. The velocity profiles in most regions of the vessel were found to depend on the opening of the basket mesh. The flow rate through the basket was predicted and found to be strongly correlated to the basket mesh size.