To understand the abilities of Ca-alginate microcapsules and their specific applications in different fields, it is necessary to determine the physicochemical and structural properties of those formulated microcapsules. In this work, we aimed to study the effect of alginate concentration in the improvement of the encapsulation efficiency (EE) and on the release of phenolic and flavonoid substances. The relationship between the structure of the encapsulated bioactive substance and Ca-alginate network and their effect on the EE and release kinetics have been investigated. The incorporation, structure, morphology, and phase properties of all elaborated materials were characterized by UV-spectroscopy, Fourier transform infrared (ATR-FTIR), scanning electron microscope (SEM), and X-ray diffraction (DRX). The results indicate that increasing the polymer concentration increases the EE and decreases the loading capacity (LC), whereas the effect of alginate polymer concentration on the release was not observed. The release study of bioactive substances showed that the release kinetics is relatively dependent on the structure and the physicochemical characteristics of the bioactive substance, which became clear when the encapsulated compounds were released from the core of calcium alginate microcapsules. Thus, it could be concluded that the pores size of the Ca-alginate network is smaller than the volume of the crocin molecule (2794.926 ų) and higher than the volume of the gallic acid molecule (527.659 ų). For the same microcapsules system, the release mechanism is affected by the structure and physicochemical properties of the encapsulated molecules.

中文翻译：

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海藻酸钠浓度对微胶囊性能的影响预测生物活性物质的保护和控制释放

要了解海藻酸钙微胶囊的能力及其在不同领域的具体应用，有必要确定这些配方微胶囊的理化和结构特性。在这项工作中，我们旨在研究海藻酸盐浓度对提高包封效率 (EE) 和酚类和黄酮类物质释放的影响。已经研究了封装的生物活性物质的结构和海藻酸钙网络之间的关系及其对 EE 和释放动力学的影响。通过紫外光谱、傅里叶变换红外 (ATR-FTIR)、扫描电子显微镜 (SEM) 和 X 射线衍射 (DRX) 对所有精心制作的材料的结合、结构、形态和相特性进行了表征。结果表明，增加聚合物浓度会增加 EE 并降低负载能力 (LC)，而未观察到藻酸盐聚合物浓度对释放的影响。生物活性物质的释放研究表明，释放动力学相对依赖于生物活性物质的结构和理化特性，当包封的化合物从海藻酸钙微胶囊的核心释放时，这一点变得清晰。因此，可以得出结论，Ca-藻酸盐网络的孔径小于藏红素分子的体积（2794.926 Å 生物活性物质的释放研究表明，释放动力学相对依赖于生物活性物质的结构和理化特性，当包封的化合物从海藻酸钙微胶囊的核心释放时，这一点变得清晰。因此，可以得出结论，Ca-藻酸盐网络的孔径小于藏红素分子的体积（2794.926 Å 生物活性物质的释放研究表明，释放动力学相对依赖于生物活性物质的结构和理化特性，当包封的化合物从海藻酸钙微胶囊的核心释放时，这一点变得清晰。因此，可以得出结论，Ca-藻酸盐网络的孔径小于藏红素分子的体积（2794.926 ų ) 并且高于没食子酸分子的体积 (527.659 Å ³ )。对于相同的微胶囊系统，其释放机制受被包封分子的结构和理化性质的影响。