尼莫地平固体分散体在速释制剂中的溶出性质(英)

为了提高难溶性药物尼莫地平的溶出度，并在此基础上研制出其速释制剂，本研究选用PVP（k30）为载体制备了尼莫地平的固体分散体及机械混合物，比较了二者体外药物溶出度及药物的结晶形态，并考查了共沉淀物的稳定性。进而进行了尼莫地平速释片剂处方的筛选，并按最优处方制备了胶囊剂。比较了自制速释胶囊剂与市售片剂的释药情况。体外实验结果表明，固体分散体对尼莫地平溶出度的提高大大优于机械混合物，5分钟的释药量，前者为89％，而后者仅为45％。X-射线衍射实验表明，尼莫地平在以PVP为载体的固体分散体中是以非晶体形式存在，并且在室温并密封于玻璃瓶中放置一年后仍无结晶出现。本研究制备的片剂和胶囊剂都具有速释性质，而以胶囊剂为优，说明压片压力可能影响溶出。速释胶囊的释药速率大大高于市售普通片剂。

The Dissolution Properties of Nimodipine Solid Dispersion Used in Fast Release Formulations

in the Present study, nimodipine-PVP solid dispersion was investigated toenhance the dissolution rate of nimodipine (NMDP), a poorly water-soluble substance, and toformulaiC the dosage forms with fast-release properties. The dissolution properties of NMDP-PVPcoprecipitate and physical mixture were compared. The physical states of NMDP in both newly-madeand one-yak-old samples of solid dispersion were also investigated by X-ray diffraction analysis.The dissolution rate of NMDP from the tablets and capsules of coprecipitate was compared with thatof two kinds of commercial tablets. The resultS shoWed that solid dispersion gave much higherimprovement than Physical mixture in the dissolution rate. In 5 min, 89% of the ding was releasedfrom solid dispersion, and 45% from physical mixture.Powder X-ray diffraction pattern showed thatNMDP was present in amorphous or molecular form in the solid dispersion while it was in crystallineform in physical mixture.There was no appearanCe of crystallization in solid diSPersion after oneyear storage in a sealed glass bottle under room temperature. Capsules and tablets of coprecipitateboth showed fast-release propefties, and the drug dissolution fate from the former was greater thanthat from the latter, suggesting that the compressing pressure could influence the dissolution rate. Itwas also demonstrated that the dissolution rate of NMDP from the selected capsules was muchgreater (about three to four times) than that from the two kinds of commercial tablets.