Dissolution rates of corticoid solutions dispersed on silicas

Two nonporous and three porous amorphous silicas were used as dispersion media to convert corticoid solutions into free-flowing powders. The corticoids (prednisone, prednisolone, and hydrocortisone) were dissolved in N,N-dimethylacetamide-polyethylene glycol 400 (7:3 v/v) and their 10% (w/v) solutions were mixed with the silicas (1:3 v/w). Dissolution rates of the corticoids from such powdered solutions were more rapid than their micronized powders in various aqueous media.