Abstract
The dissolution step of practically insoluble drugs plays an important role in drug absorption. In this paper, the pharmaceutical properties of a ground mixture of nifedipine are described. A ground mixture of nifedipine was prepared by grinding with casein, magnesium silicate, and cellulose acetate phthalate in a vibrational ball mill. The X-ray powder diffraction patterns and differential scanning calorimetry data thereafter suggested that nifedipine was present in its amorphous form in the ground mixture. The wettability of the ground mixture was better than that of the physical mixture. The solubility of amorphous nifedipine in water was also better than that in crystalline. Both the dissolution rate and the bioavailability of amorphous nifedipine in the ground mixture were significantly greater than those of the physical mixture. The above results thus suggest that a mixture grinding method not only improves the solubility of nifedipine and the dissolution profile of its preparation but also enhances its bioavailability after oral administration.
