Fast Release and Physicochemical Characteristics of Nifedipine Solid Dispersions with Poloxamers

抄録

Solid dispersions of nifedipine (NP) with three types of poloxamers (PXMs), namely, PXM 188, PXM 288 and PXM 407, were prepared by melting, solvent and kneading methods to improve the NP dissolution characteristics. The melting method gave the highest enhancing effect to the dissolution rate (p<0.05), followed by the solvent and kneading methods. The highest dissolution rate was obtained from PXM 188 prepared by the melting method at the 1:10 drug:carrier mixing ratio. The possible mechanisms for dissolution improvement obtained from the X-ray diffraction and differential scanning calorimetric studies were discussed. The amorphization of the drug at the higher mixing ratio, the improvement of the wettability and the solubility seemed to participate in the fast release mechanisms of NP. Moreover, the infrared spectra showed the presence of intermolecular hydrogen bonding between drug molecules and poloxamers.