Effect of processing technique of different dosage forms on dissolution rate of caffeine and salicylamide

The dissolution rate of caffeine (Cf) and salicylamide (SA) from the mixtures of powders, granulate and tablets, obtained by the direct compression and wet granulation methods, has been investigated. The results presented in plots show, that the dissolution process of Cf and SA follows the first-order kinetics. The kinetic equations are used for the calculation of the dissolution rate contants (K) for the compounds of different solubility. Chromatography did not give an evidence for the formation of an adduct of Cf and SA in the granulate and tablets prepared by the wet granulation method.