目的 针对黄芩Scutellaria baicalensis黄酮类化合物水溶性不佳的问题，探索合理的解决策略。方法 通过变换溶剂类型，分别选用甲醇、乙醇、水及75%乙醇作为提取溶剂，采用超声辅助技术提取黄芩饮片中的有效成分。利用冷场发射扫描电子显微镜（scanning electron microscope，SEM）观察不同溶剂所得提取物的微观结构，通过紫外分光光度法与标准曲线法对黄芩饮片中黄芩黄酮进行定量分析。进一步采用¹H-NMR法明确组装体中主要化合物的结构。通过自组装与物理交联技术，制备了黄芩黄酮调控结构的水凝胶，利用SEM对比分析了基底水凝胶与黄芩黄酮复合水凝胶的形貌特征。采用流变学方法评估了2类水凝胶的流变性能，同时运用红外光谱技术分析了相互作用方式。通过溶胀性测试和缓释性能测试实验，分别探究了复合水凝胶中黄芩黄酮的调控作用和释放行为，并利用自由基清除实验评估了黄芩黄酮调控水凝胶的抗氧化性能。结果 在超声辅助提取过程中，黄芩黄酮展现出与溶剂种类及超声功率密切相关的自组装特性。壳聚糖弱酸溶液（pH 3.0～3.5）的引入，显著提升了黄芩黄酮的溶解度，并通过氢键作用实现了对高分子网络结构的浓度相关性调控。随着黄芩黄酮质量浓度的增加，水凝胶的网络结构变得更加致密且均匀，比表面积增大，孔隙尺寸介于微米与亚微米之间，这一结构特征有效延长了黄芩黄酮的释放时间。释放出的黄芩黄酮表现出高效的自由基清除能力，制备的水凝胶敷料能够显著促进大鼠慢性炎症伤口愈合。结论 展示了黄芩黄酮提取过程中的溶剂效应，为合理选择提取溶剂提供了依据；提供了制备结构可调控水凝胶敷料的方法，为提高中药活性成分的生物利用度及设计高性能止血水凝胶敷料提供了理论基础。

Objective Exploring an effective method to tackle the poor water solubility of Huangqin (Scutellaria baicalensis) flavonoids is necessary. Methods We conducted an extraction of S. baicalensis slices flavonoids using four different solvents: methanol, ethanol, water, and 75% ethanol, all assisted by ultrasonication. To observe the morphological structures of the extracts obtained with these solvents, scanning electron microscopy (SEM) was employed. For quantitative analysis of the flavonoids from S. baicalensis slices, we utilized ultraviolet spectrophotometry in conjunction with the standard curve method. The structural analysis of the main compounds in the extracts was performed using ¹H-NMR spectroscopy . Furthermore, we prepared hydrogels with controlled structures incorporating flavonoids through self-assembly and physical crosslinking techniques. The morphologies of both the plain hydrogel and the flavonoid-incorporated composite hydrogel were analyzed using SEM. Rheological assessments were performed to evaluate the rheological properties of these two types of hydrogels. To gain insights into the interactions within the hydrogels, Fourier transform infrared spectroscopy (FT-IR) was applied. Additionally, we conducted the release behavior of flavonoids from the composite hydrogel. To assess the antioxidant properties of the hydrogel regulated by flavonoids, free radical scavenging experiments were also performed. Results During ultrasound-assisted extraction, the flavonoids from S. baicalensis exhibited self-assembly behavior dependent on solvent type and ultrasonic power. Dissolution was notably enhanced in chitosan (CS) weak acid solution (pH 3.0—3.5). Through hydrogen bonding interactions, we achieved concentration-dependent structural regulation of the polymer network. As the concentration of flavonoids increased, both the network density and uniformity of the resulting hydrogel improved, accompanied by an increase in its specific surface area. Observed pore sizes from micro- to submicron scale prolonged the release of encapsulated flavonoids. Furthermore, the released flavonoids exhibited a high capacity for free radical scavenging, and the prepared hydrogel dressing can significantly promoted the healing of chronic inflammatory wounds in rats. Conclusion This work demonstrates the solvent effect in the extraction process of traditional Chinese medicines, providing a basis for the rational selection of extraction solvents. Moreover, it presents a method for preparing hydrogel dressings with controllable structures, offering a useful theoretical foundation for enhancing the bioavailability of flavonoids in traditional Chinese medicines and designing high-performance hemostatic hydrogel dressings.

R283.6

国家自然科学基金资助（22405231）；河南省自然科学基金资助（2300420388）；河南省大学生创新创业培训计划（202410477039）；河南省大学生创新创业培训计划（202410477041）；南湖青年学者计划（202509）；河南省高等学校重点科研项目（25B350006）