A common query with regard to a dissolution test is how one should conduct the test for a drug. Further, in response to such queries, different suggestions are made for choosing the apparatus, rpm, medium etc. However, unfortunately, such queries and the responses lack scientific merit and logical thinking. The reason is that a dissolution test is conducted for a product and not for a drug (active ingredient). That is why pharmacopeial monographs, in particular USP, do not have dissolution tests under drugs (active ingredients) but products.
Therefore, one can only suggest a testing procedure for products and not for drugs. Further, a testing procedure is not, or should not, be linked to a product, because testing is done to evaluate product. Therefore, the procedure must be product independent. The question then becomes how one should set up the experimental conditions. The answer is that the dissolution testing conditions should be reflective of the GI tract environment, in particular intestinal. As the GI tract environment does not change from product to product, the testing procedure therefore should be fixed as well.
A common testing environment may be based on water maintained at 37 °C, with some solubiliser to dissolve low aqueous solubility drugs, and a simple stirring mechanism which should provide efficient/thorough product-medium interaction. Hope this suggestion will help in answering the common and frequent queries.
