...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of pharmaceutical sciences. >Feasibility of Atomic Force Microscopy for Determining Crystal Growth Rates of Nifedipine at the Surface of Amorphous Solids with and Without Polymers
【24h】

Feasibility of Atomic Force Microscopy for Determining Crystal Growth Rates of Nifedipine at the Surface of Amorphous Solids with and Without Polymers

机译：用原子力显微镜测定硝苯地平在有或没有聚合物的非晶态固体表面的晶体生长速率的可行性

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

Amorphous nifedipine (NFD), which has a smooth surface immediately after preparation, was shown to have structures resembling clusters of curling and branching fibers approximately 1 mum wide by atomic force microscopy (AFM) after storage at 25°C. The size of the cluster-like structures increased with storage over time, implying crystal growth. The average elongation rate of the fibers determined by AFM at ambient room temperature was 1.1 x 10~(-9) m/s, and this agreed well with the crystal growth rate of 1.6 x 10~(-9) m/s determined by polarized light microscopy. The crystal growth rate of NFD in solid dispersions with 5% polyethylene glycol (PEG) was found to be 5.0 x 10~8 m/s by AFM. Although this value was approximately the same as that obtained by polarized light microscopy, three-dimensional information obtained by AFM for the crystallization of NFD in a solid dispersion with PEG revealed that the changes in topography were not a consequence of surface crystal growth, but rather attributable to the growth of crystals formed in the amorphous bulk. For solid dispersions with alpha,Beta-poly(N-5-hydroxypentyl)-L-aspartamide, acceleration of NFD crystallization by tapping with an AFM probe was observed. The present study has demonstrated the feasibility and application of AFM for interpretation of surface crystallization data.
机译：制备后立即具有光滑表面的无定形硝苯地平（NFD），在25°C储存后，通过原子力显微镜（AFM）具有类似于卷曲和分支纤维簇的结构，约1毫米宽。簇状结构的尺寸随时间的推移而增加，这意味着晶体生长。 AFM在室温下测得的平均纤维伸长率为1.1 x 10〜（-9）m / s，与晶体生长速率为1.6 x 10〜（-9）m / s吻合得很好。偏光显微镜。通过AFM发现NFD在具有5％聚乙二醇（PEG）的固体分散体中的晶体生长速率为5.0×10〜8m / s。尽管该值与通过偏光显微镜获得的值大致相同，但是通过AFM获得的NFD在PEG固体分散体中结晶的三维信息表明，形貌变化不是表面晶体生长的结果，而是表面晶体生长的结果。这归因于无定形体中形成的晶体的生长。对于具有α，β-聚（N-5-羟基戊基）-L-天冬酰胺的固体分散体，观察到通过用AFM探针敲击加速了NFD结晶。本研究证明了AFM解释表面结晶数据的可行性和应用。

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