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Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
预测微气候的pH值在多 (乳酸-co-甘油酸) 薄膜
Amy G Ding1, Anna Shenderova, Steven P Schwendeman
1Department of Pharmaceutical Sciences, The University of Michigan, Ann Arbor, Michigan 48109-1065, USA.
Journal of the American Chemical Society
|April 20, 2006
概括
一个新的数学模型准确地预测了聚乳糖合糖酸 (PLGA) 薄膜中的微气候pH值. 这种模型对于控制可生物降解聚合物的pH敏感药物的释放至关重要.
科学领域:
- 生物材料科学 生物材料科学
- 聚合物化学 聚合物化学
- 数学建模的数学建模
背景情况:
- 像PLGA这样的可生物降解聚合物在药物输送中被广泛使用.
- 控制这些聚合物内的微环境pH值对于封装物质的稳定性和释放至关重要.
- 现有的模型往往缺乏准确预测微气候pH (mupH) 的精度.
研究的目的:
- 开发和验证一个平衡数学模型来预测PLGA膜中的muphH.
- 确定生物可降解聚合物的mupH动态的关键因素.
- 建立一个框架来预测降解产品的分区行为.
主要方法:
- 在pH玻璃电极上涂层PLGA聚合物,用于电位测量mupH测量.
- 使用预衍生物化的高性能液态染色学 (HPLC) 来量化水溶性酸的含量和分布.
- 开发了一个数学模型,其中包含了水溶性酸动力学和聚合物/水分区系数 (P(i)).
主要成果:
- mupH模型准确地预测了各种PLGA组合和时间点的实验值.
- 聚合物降解产品显示出有利的分离到聚合物相 (P(i) 范围:6-100).
- 分割系数 (P(i)) 与酸性物种的疏水性正相关.
结论:
- 开发的数学模型可以准确地预测PLGA膜中的muph.
- 了解降解产品分离是控制聚合物微气候的关键.
- 该模型可以帮助设计使用PLGA的pH敏感生物活性物质的可控释放系统.
相关概念视频
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