(563e) Investigations of Intra-Tablet Coating Variability in a Side-Vented Pan Coater Via Digital Video Analysis

Coatings are applied to pharmaceutical tablets for a number of reasons ranging from aesthetic purposes to providing protection of the tablet cores from the environment or controlling the release profiles and ultimately bioavailability of the drug (i.e. functional coatings). Usually these coatings are sprayed onto tablet batches contained within horizontal rotating pans. A successfully coated tablet batch will have a prescribed coating thickness on each tablet's surface with little inter- and intra-tablet variability.

A method for estimating the intra-tablet coating variability from video-based experiments and analyses is presented. The orientation of bi-convex tablets passing through the spray zone for a range of processing conditions is measured and expressed in terms of an orientation index. The orientation index is in turn related to the intra-tablet coating variability. Predictions of intra-tablet coating variability from video-based experiments are found to closely match measurements from actual coating experiments. Data from the video-based method may also be used to investigate the effects of pan speed, tablet load, baffle design, and drying air and can also monitor transitions in the tablet bed dynamic behavior.