期刊
BIOMATERIALS
卷 23, 期 13, 页码 2795-2801出版社
ELSEVIER SCI LTD
DOI: 10.1016/S0142-9612(02)00016-9
关键词
silica gel microparticles; spray drying; dexmedetomidine; in vivo
The objective of this study was to evaluate the possibilities to control the release rate of dexmedetomidine (DMED) from different spray-dried silica gel microparticle formulations. Microparticles were prepared by spray drying a silica sot polymer solution containing the drug. Drug release was investigated both in vitro and in vivo. The influence of sol-gel synthesis parameters like pH and the water/alkoxide ratio (r) of the sot, on the release behaviour of the drug, vas studied. Silica gel microparticles had a smooth surface. Microparticles prepared from diluted sot, however were more aggregated and clustered. The drug release conformed to zero order release from microparticles prepared near the isoelectric point of silica (pH 2.3 and pH 3) and to the square root of time kinetics from microparticles prepared at pH 1 and pH 5. The release also showed a dual-phasic profile with an initial burst and after that a slower release period. The dexmedetomidine release conformed to zero order kinetics from microparticles prepared at water/alkoxide ratios between r = 6 and r = 35 (at pH 13). The release rate was the slowest from microparticles prepared with water alkoxide ratio 35. The bioavailability of dexmedetomidine in dogs showed that the release was sustained from silica gel microparticles as compared with a subcutaneously administered reference dose of 0.1 mg. (C) 2002 Elsevier Science Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据