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Updated: Sep 11, 2025

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The Diffusion of Passive Tracers in Laminar Shear Flow
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在双相扩散装置中对粒子漂移效应的质量运输分析
Saurav Adhikari1, Da Hye Yang1, Na Li2
1Department of Pharmaceutical Sciences, University of Connecticut, 69 North Eagleville Road Unit 3092, Storrs, CT 06269, United States.
Journal of pharmaceutical sciences
|August 15, 2025
概括
这项研究引入了一种新的模型,以了解无形药物纳米颗粒如何通过降低阻隔电阻来改善口服吸收. 该模型准确预测药物吸收,有助于开发更好的药物输送系统.
科学领域:
- 制药科学 制药科学
- 药物运输 药物运输 药物运输
- 物理化学 物理化学
背景情况:
- 合式配方 (小粒,纳米晶体,无形药物纳米颗粒) 增强了难溶药物的口服吸收.
- 粒子漂移效应,减少吸收点附近的扩散电阻,是拟议的机制.
- 准确地解释和预测这种效应仍然具有挑战性.
研究的目的:
- 开发一个综合溶解-透模型,用于对粒子漂移效应的定量分析.
- 用双相实验设置评估无形药物纳米粒子.
- 提供机理性理解和改善口服生物可用性预测.
主要方法:
- 开发了一种集成的溶解-透模型,将Wang-Flanagan粒子溶解模型与停滞膜透模型相结合.
- 利用双相实验设置来评估不溶性药物的无形药物纳米粒子.
- 将大众运输模型与用于体内预测的药理动力学模型集成.
主要成果:
- 低颗粒度没有改变扩散形状或透系数.
- 高颗粒度显示流量平原 (非沉溶解) 和增加界面透性.
- 颗粒物的存在改变了由于水界层中的和效应而适合的分区系数.
结论:
- 开发的模型量化分析了粒子漂移效应,证实了在高颗粒度下降的扩散电阻.
- 该模型准确地预测了对具有挑战性的系统 (高度,极难溶解的药物) 的粒子漂移效应.
- 这项工作增强了对扩散形状的理解,并有助于预测纳米粒子配方的口服生物可用性.
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