The effect of blending time on particle adhesion in a model interactive system.

The adhesive tendency of drug particles in a model drug carrier interactive system increased with blending time. The degree of interaction was measured using a centrifuge technique; the resultant adhesion profile of per cent retained on the carrier versus the square of the speed of rotation was a logarithmic normal function that allowed the determination of the S50 to characterize the adhesion tendency. The relative degree of adhesion of the drug particles in the interactive mixtures and the rate to attain adhesion saturation in the interactive system during the mixing process was markedly different for the three mixtures studied. The increased adhesive tendencies during blending were probably associated with triboelectrification of the drug and carrier particles.