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Updated: May 3, 2026

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Generation of Alginate Microspheres for Biomedical Applications
Published on: August 12, 2012
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对酸盐/Ca2+和酸盐/Fe3+珠子进行比较研究:密度函数计算和香油释放
Renata P Sanches1, Luis Octavio de Araujo2, Letícia F Balcewicz1
1Grupo de Pesquisa em Macromoléculas e Interfaces, Department of Chemistry, Universidade Federal do Paraná, Curitiba, Paraná, Brazil.
International journal of biological macromolecules
|December 13, 2025
概括
铁酸盐珠子提供较慢的精油释放比酸盐珠子由于更强的相互作用. 这种结构差异影响释放动力学,特别是在不同的pH值水平.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 甲基酸盐 (SA) 珠子被广泛用于封装.
- 像 (Ca2+) 和铁III (Fe3+) 这样的交联剂会影响珠子的结构和释放特性.
- 了解酸盐-酸盐相互作用对于控制精油释放至关重要.
研究的目的:
- 为了比较研究与Ca2+或Fe3+交联的SA珠的结构组织,相互作用能量和精油释放行为.
- 用密度函数理论 (DFT) 阐明热力学稳定和结构特征背后的机制.
- 评估pH值对阴离子稳定性和精油释放的影响.
主要方法:
- 密度函数理论 (DFT) 用于表征离子-酸盐相互作用.
- 在SA珠子中封装贝加莫特精油 (BEO).
- 珠子形态和阴离子分布的表征 (ICP-OES).
- 在不同的pH条件下分析BEO释放动力学.
主要成果:
- 铁酸盐珠比Ca酸盐珠具有更强的共价性质,具有更紧的结构.
- 与Ca-alginate珠子相比,Fe-alginate珠子的BEO释放速度较慢,特别是在中性pH下.
- 在酸性pH条件下,珠子的Ca2+损失更高,而在酸性条件下,Fe3+损失更高,表明pH依赖的稳定性.
- 封装产量对于Ca2+珠子 (80.9重%) 比Fe3+珠子 (54.3重%) 高.
- BEO的释放采用了扩散控制机制 (Korsmeyer-Peppas模型),并且在酸性pH下更快.
结论:
- 铁酸盐珠中的更强的共价相互作用导致增强的结构稳定性和受控的BEO释放.
- pH显著影响了阴离子稳定性和离子交换,影响了封装精油的释放率.
- DFT 提供了对电子属性的有价值的见解,这些属性控制了酸-酸相互作用和珠子性能.
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