...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Microencapsulation: Microcapsules Liposomes Nanoparticles Microcells Microspheres >Oxprenolol-loaded bioadhesive microspheres:preparation and in vitro/in vivo characterization
【24h】

Oxprenolol-loaded bioadhesive microspheres:preparation and in vitro/in vivo characterization

机译：载有氧戊烯醇的生物粘附微球：制备及体外/体内表征

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Biologically adhesive delivery systems offer important advantages over conventional drug-delivery systems.In this paper,microspheres intended as a sustained release carrier for oral or nasal administration have been prepared by associating a known bioadhesive polymer,poly(acrylic acid),in gelatin microspheres.A model drug oxprenolol hydrochloride was chosen.It was found that some of the formulation variables can influence the characteristics of the beads in a controlled manner.The internal structure of the microspheres studied by X-ray diffraction,thermal analysis and optical microscopy showed the absence of drug crystals in microspheres and a lowering in the glass transition temperature.The dynamic swelling of the beads obeyed the square root of time and a shift from the diffusional to the relaxational process dependent on the content of poly(acrylic acid)in gelatin microspheres was observed.As expected,drug release from gelatin/poly(acrylic acid)micro- spheres was influenced by the poly(acrylic acid)content in beads,by the particle size of microspheres and by the pH of the medium.The mechanism of release was analysed by applying the empirical exponential equation and by calculation of the approximate contribution of the diffusional and relaxational mechanisms to the anomalous release process by fitting the data to the coupled Fickian/Case II equation.In vitro and in vivo experiments in rats showed good adhesive characteristics of the gelatin/poly(acrylic acid)microspheres,which were greater if the poly(acrylic acid)content was greater.A significant retardation in gastric and intestinal emptying time of the beads was observed.This was also suggested by the bioavailability of the model drug after intragastric and intranasal administration of the microspheres.The pharmacokinetic parameters after microsphere administration were more appropriate to a slow release drug-delivery system.The work suggests the potential of this pharmaceutical delivery system as an alternative controlled-release dosage form,either for oral or nasal administration.
机译：生物粘合剂递送系统提供了优于常规药物递送系统的重要优势。在本文中，通过将已知的生物粘合剂聚合物聚丙烯酸与明胶微球缔合，制备了用于口服或鼻腔给药的缓释载体的微球。选择了模型药物盐酸盐酸戊烯诺尔，发现一些制剂变量可以控制方式影响微珠的特性。X射线衍射，热分析和光学显微镜研究的微球内部结构表明不存在微球中的药物晶体含量降低，玻璃化转变温度降低。珠粒的动态溶胀服从时间的平方根，并且从扩散到松弛过程的转变取决于明胶微球中聚丙烯酸的含量。如预期的那样，明胶/聚（丙烯酸）微球中的药物释放受到p的影响。通过微球的粒径和介质的pH值，可以确定珠粒中oly（丙烯酸）的含量。通过经验指数方程，并通过计算扩散和弛豫机制对颗粒的近似贡献，分析了释放机理。通过将数据拟合为耦合的Fickian / Case II方程来进行异常释放过程。大鼠体内和体外实验表明，明胶/聚（丙烯酸）微球具有良好的粘附特性，如果聚（丙烯酸）含量更高观察到珠子的胃和肠排空时间显着延迟，这也由模型药物在胃内和鼻内给药微球后的生物利用度所暗示，微球给药后的药代动力学参数更适合缓慢释放药物递送系统。这项工作表明该药物递送系统作为替代产品的潜力ve控释剂型，用于口服或鼻腔给药。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号