Vessel Validation
Vessel design is something that is often overlooked by the analyst. The USP allows for a significant variation in the specification of the vessels with a height of 160-170mm and an ID of 98-106mm. This variation means that if vessels are changed in the bath then the paddle height and centering measurements need to be rechecked. If the vessels are serialised then they should be kept in the same position. As well as the physical dimensions the vessels should be smooth and scrupulously clean. Small ridges on the inside of the vessel can greatly increase the dissolution rate whilst scratches and sticky or gummy patches can reduce them.