...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>European journal of pharmaceutics and biopharmaceutics: official journal of Arbeitsgemeinschaft fuer Pharmazeutische Verfahrenstechnik e.V >Determination of ice interface temperature, sublimation rate and the dried product resistance, and its application in the assessment of microcollapse using through-vial impedance spectroscopy
【24h】

Determination of ice interface temperature, sublimation rate and the dried product resistance, and its application in the assessment of microcollapse using through-vial impedance spectroscopy

机译：冰界面温度，升华速率和干燥产品抗性的测定及其在使用通过小瓶阻抗光谱法评估微污觉的应用

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

Through-vial impedance spectroscopy (TVIS) is a new approach for characterizing product attributes during freeze-drying process development. In this study, a pair of copper foil electrodes was attached to the external surface of a Type I glass tubing vial, of nominal capacity 10 mL and containing 3.5 g of an aqueous solution of 5% w/v lactose, and the impedance spectrum of the vial and contents recorded during a lyophilization cycle. The cycle included a temperature ramp in the primary drying stage in order to induce a collapse event in the dry layer. Using the peak in the dielectric loss spectrum, associated with the dielectric relaxation of ice, methods were developed to predict the sublimation rate and the ice interface temperature at the sublimation front, from which the dry layer resistance was then calculated. A four-fold increase in sublimation rate and a reduction in the dry layer resistance wereobserved once the ice interface temperature reached -33 degrees C, which coincides with the onset of the glass transition (as determined by DSC) and the time point at which micro-collapse occurred (as evidenced by SEM images at the end of the cycle). This work suggests a prospective application of impedance measurements in driving process efficiencies by operating the dryer at the highest achievable temperature (i.e. the collapse temperature) whilst avoiding macro-collapse.
机译：通过小瓶阻抗光谱（TVIS）是一种新方法，用于在冻干过程开发期间表征产品属性。在该研究中，将一对铜箔电极连接到I型玻璃管小瓶的外表面，标称容量10mL，含有3.5g的5％w / v乳糖的水溶液，以及阻抗谱在冻干循环期间记录的小瓶和内容物。该循环包括初级干燥阶段的温度斜坡，以便在干燥层中诱导塌陷事件。在介电损耗光谱中使用与冰介电弛豫相关的峰值，开发了方法以预测升华前沿的升华速率和冰界面温度，然后计算干燥层电阻。一旦冰界面温度达到-33℃，升华率的升华速率增加和干燥层电阻的减少，这与玻璃转变的开始（如DSC确定）和微量微量的时间点一致-Collapse发生（如循环结束时的SEM图像所证明）。这项工作表明，在避免宏崩溃时，通过在最高可实现的温度（即塌陷温度）下通过操作干燥器来驾驶过程效率的预期应用。

著录项

相似文献

  • 外文文献
  • 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