Dissolution studies with a multichannel continuous-flow apparatus.

A multichannel continuous-flow apparatus for dissolution rate measurements is described. Typical data are presented to demonstrate its utility for studies with bulk drug powders as well as with tablets and capsules without any change of setup. Procedures are given for the preparation of powder samples for dissolution studies and for a simple method of changing pH for "retard" tablets. The precision in dissolution rates obtained with this apparatus and method is 1-10% mean RSD. The advantages of the method are flexibility, reproducibility, and ability to obtain data in integral or differential form.