Dissolution behaviour of drugs from binary and ternary systems

Abstract

Dissolution profiles of oxodipine and griseofulvin were obtained from binary and ternary systems prepared with PEG 6000 and PEG 6000/Tween 20, respectively. The improvement obtained in drug dissolution from physical mixtures prepared in several proportions with PEG 6000 is due to the disaggregant action of the hydrophilic carrier. This agent reduces the electrostatic forces that maintain the drug particles united together. During the preparation of solid dispersions an interaction between the two components is produced; this phenomenon explains the enhancement in the dissolution profile of the incorporated drug. Also, an increase in drug dissolution rate is observed to increase the proportion of carrier in these binary systems, since it also increases the amount of drug that interacts with PEG 6000 during preparation. The dissolution of drugs (oxodipine or griseofulvin) from ternary systems, drug/PEG 6000/Tween 20, is better than that obtained from the respective binary systems, since in the former the wetting action of surfactant agent and the solubilizing effect of PEG 6000 over drug are additive.