在冷和冷化后,甘氨酸和L-histidine缓冲剂,曼尼托尔及其混合物中的酸度变化
Lukáš Veselý1, Jan Ryšávka1, Radim Štůsek1
1Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic.
International journal of pharmaceutics
|January 10, 2026
概括
冷和冷可以改变配方的pH值,影响分子稳定性. 这项研究表明,虽然结稍微增加了pH值,但冷化会导致显著的酸化,特别是在L-histidine缓冲区.
科学领域:
- 制药科学 制药科学
- 生物化学 生物化学
- 物理化学 物理化学
背景情况:
- 冷和冷是常见的稳定技术,用于制药和生物化学配方.
- 冷引起的压力,特别是pH值的变化,可以破坏活性分子的稳定,导致聚合和完整性丧失.
- 标准缓冲器在冷时可能无法保持pH值,甚至可以加剧酸度变化.
研究的目的:
- 研究冷却速率,初始pH值,曼尼托度和冷化对甘氨酸和L-histidine缓冲系统中的酸度的影响.
- 了解玻璃化和冷引起的酸度变化之间的关系,使用哈梅特酸度函数.
- 为设计敏感配方的改进稳定策略提供见解.
主要方法:
- 使用UV-VIS光谱和差分扫描热度计来分析冷和冷缓冲系统中的酸度变化.
- 该研究在不同的条件下检查了甘氨酸和L-histidine缓冲系统,包括冷却速度,初始pH值和曼尼托度.
- 哈梅特酸度函数 (H2-) 用于量化酸度变化并将其与玻璃化相关联.
主要成果:
- 氨基酸缓冲区的结导致pH值略微增加 (基化).
- 酸度的变化不仅在冷过程中观察到,而且在冷过程中也观察到.
- 在pH 7下,L-histidine与曼尼托尔的冷化诱导了显著的酸化 (高达4个单位),与冷时看到的基化形成鲜明对比.
结论:
- 结和冷都对制药缓冲系统的酸度产生重大影响.
- 冷可以诱导大量的pH值变化,这取决于配方,并且可能与冷时观察到的相反.
- 了解这些pH动态对于合理设计经过冷干燥的稳定制药和生物化学配方至关重要.
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