Evaluation of mathematical models describing drug release from lipophilic matrices

Potassium chloride, as a highly watersoluble model drug was embedded into wax to produce sustained release dosage form. Samples were coated with different core:wall ratios to control the dissolution profile. The drug release from coated samples was tested by the rotating paddle method of USP and the dissolution data were analyzed assuming different kinetic models. Increasing the quantity of coating material may modify the drug liberation which was demonstrated by the correlation between proportion of the embedding material and mean dissolution time. It can be concluded that changing the quantity of embedding material both the dissolution rate and kinetic profile can be controlled.