Systematic error associated with apparatus 2 of the USP dissolution test V: Interaction of two tableted prednisone...

Recently marketed glass vessels that are uniform and pass USP specifications were compared with uniform plastic vessels that also pass USP specifications. Two lots of prednisone tablets, Tablet 1 and Tablet 2, were tested in both types of vessels. Tablet 1 gave higher results (+12.7% of label claim) in glass vessels at 50 rpm but gave equivalent results in either vessel at 75 rpm. Tablet 2 gave equivalent results in either vessel at 50 rpm but gave higher results (+22% of label claim) in glass vessels at 75 rpm. The type of vessel used to obtain dissolution results for tablets should be specified.