(470f) Hydrodynamics Investigation of USP Dissolution Testing Apparatus I (Basket Apparatus) and Effect of the Basket Mesh Size on Hydrodynamic Characteristics

The United States Pharmacopoeia (USP) develops and disseminates compendial quality standards for drug products and other pharmaceutical products, including the dissolution testing methods routinely used in industry and typically accepted by FDA. The USP Dissolution Testing Apparatus I is commonly used as an analytical tool to evaluate the performance of solid drug products and to determine if a drug formulation is within the acceptance standard criteria. In this test the drug oral dosage form, typically a tablet, is placed in a perforated basket immersed in a small volume-vessel and rotating at constant fixed speed. The tablet dissolution process is followed over time by taking samples from the liquid and determining the dissolved drug concentration. Several reports in the literature have indicated that there is considerable variability in the dissolution profiles obtained with this dissolution testing apparatus. One of the most likely reasons for this is the susceptibility of the apparatus to small variation in the system’s geometry often introduced through minor deviations of the actual system from perfect symmetry or the use of baskets of different mesh sizes. The objective of this work was to determine the fluid flow in the dissolution apparatus with standard basket mesh size under different operating conditions using Particle Image Velocimetry (PIV) as an experimental tool and to investigate and compare the velocity distribution profiles obtained using different basket mesh sizes. The results indicate that variation in geometric parameters and operating variables within standard criteria appear to significantly affect the hydrodynamics of these systems contributing to the variability of dissolution testing results. The results of this work can provide a better understanding of the hydrodynamic factors affecting the dissolution process in this apparatus and indicate possible approaches to minimize variation in dissolution test results.