Understanding disintegrant action by visualization.

The aim of this study was to utilize high-speed video imaging for understanding the disintegrability of compacts and disintegrant action upon wetting. High-speed video imaging was used to visualize the disintegration of compacts and effect of wetting on free disintegrant particles. Acquired images were processed using MATLAB, and changes in the compact area and instantaneous motion of compacted particles on contact with water were analyzed. The capillary action of compacts was also determined for various disintegrants. Finally, the breakdown behavior of compacts prepared with selected disintegrants was analyzed at different compression forces to evaluate recovery of compaction strain. Water-insoluble inert diluent, dicalcium phosphate, was used as a comparator. The results from this visualization study provided an in-depth understanding of the disintegrant behavior of free and compacted disintegrant particles upon wetting. The mechanisms of swelling, capillary action, disruption of particle-particle bonds and strain recovery were successfully monitored by video imaging. The disintegration of compacts containing crospovidone appeared to be less influenced by swelling or wicking action. The influence of compression force on the disintegration of selected disintegrants confirmed that strain recovery is the dominant mechanism for the disintegrant action of crospovidone.