The aim of this study was the optimization of the gallic acid (GA) encapsulation efficiency within calcium alginate microparticles by the ionotropic gelation technique, using Box-Behnken design for the surface methodology response. For this purpose, three independent variables were selected: sodium alginate concentration (X1), calcium chloride concentration (X2), and gallic acid concentrations (X3). The influence of each variable on the encapsulation efficiency was evaluated. The optimum conditions to reach maximum encapsulation efficiency were found to be: X1 = 30 g/l (3%, w/v), X2 = 21.63 g/l (2.163%, w/v) and X3 = 15 g/l (1.5%, w/v), respectively. The encapsulation efficiency was determined to be 42.8%. The obtained microbeads were further examined using differential scanning calorimetry (DSC) and Fourier transform infrared (ATR-FTIR), and the inclusion of gallic acid was confirmed. The gallic acid concentration (X3) is the statistically significant factor in the optimization process. In addition, no autoxidation of the gallic acid compound was observed in the formulated calcium alginate microbeads. Scanning electron microscope (SEM) analysis showed that the shape of the particle was spherical for all formulations and their surface is wrinkled. The release study of the gallic acid carried out in an aqueous medium at pH value 6.8, showed that the GA release pattern was fast for all systems studied (85% at 20 min), and the profile of the release was influenced by the size of the calcium alginate microbeads. The obtained results reveal that the calcium alginate microbeads prepared through the ionotropic gelation technique possess great prominent for gallic acid encapsulation as well as its liberation.

中文翻译：

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使用 Box-Behnken 实验设计优化海藻酸钙微珠中没食子酸的包封

本研究的目的是通过离子型凝胶技术优化海藻酸钙微粒中没食子酸 (GA) 的封装效率，使用 Box-Behnken 设计进行表面方法响应。为此，选择了三个自变量：海藻酸钠浓度 (X1)、氯化钙浓度 (X2) 和没食子酸浓度 (X3)。评估了每个变量对封装效率的影响。发现达到最大包封效率的最佳条件是：X1 = 30 g/l (3%, w/v), X2 = 21.63 g/l (2.163%, w/v) 和 X3 = 15 g/l ( 1.5%，w/v)，分别。包封效率确定为42.8%。使用差示扫描量热法 (DSC) 和傅里叶变换红外 (ATR-FTIR) 进一步检查获得的微珠，并确认含有没食子酸。没食子酸浓度 (X3) 是优化过程中的统计显着因素。此外，在配制的海藻酸钙微珠中没有观察到没食子酸化合物的自氧化。扫描电子显微镜 (SEM) 分析表明，所有配方的颗粒形状均为球形，其表面有皱纹。在 pH 值为 6.8 的水性介质中进行的没食子酸的释放研究表明，所有研究的系统的 GA 释放模式都很快（20 分钟时为 85%），并且释放曲线受藻酸钙微珠。