硝苯地平-聚乙烯吡咯烷酮固体分散物的制备及其体外溶出度的研究

 目的 采用制剂技术提高难溶性药物硝苯地平体外溶出速率。方法 以聚乙烯吡咯烷酮（PVP-K30）为载体，制备了药物与载体不同比例的固体分散物及机械混合物，并采用差示热分析（DTA）和X-射线衍射方法，比较了二者及药物的结晶形态，并进行体外药物溶出度的测定。结果 固体分散物体外溶出速率明显高于机械混合物及硝苯地平原料药的体外溶出速率，且随载体比例增加而增大。固体分散物的X-射线衍射及DTA图谱确定了硝苯地平以无定形态分散在载体中，放置6个月后，固体分散物X-射线衍时图谱无明显变化。结论 药物与载体合适比例的固体分散物明显提高其体外溶出速率。

Studies on preparation and dissolution of the solid dispersions of nifedipine-polyvinylpyrrolidone

OBJECTIVE The solid dispersion method was adopted to enhance the dissolution rate of nifedipine (NFDP) which is a poorly water-soluble drug.METHOD Solid dispersions and physical mixtures with different proportion of weight of NFDP and PVP were prepared by using polyvinylpyrrolidone (PVP) as a carrier.The physical states of NFDP were investigated by X-ray powder diffraction analysis and DTA. The dissolution rate of NFDP from solid dispersions and from physical mixtures were also compared.RESULTS The dissolution rate of NFDP-PVP solid dispersions was much faster than that of the physical mixtures, and tended to increase with the increase of the proportion of the carrier. The X-ray power diffraction and DTA showed that the drug in the solid dispersion existed in amorphous form, and there were no significant changes for the solid dispersion kept in dry place for six months.CONCLUSION The dissolution rate of NFDP can be improved greatly by solid dispersions with proper ratio of drug and carrier.