目的 探究甘草酸凝胶的流变学性质及其对疏水性药物橙皮苷的增溶作用。方法 采用旋转流变仪对不同制备条件得到的甘草酸凝胶进行应变扫描实验与稳态流动实验，探究甘草酸质量浓度、溶剂pH值、金属离子种类和质量浓度对甘草酸凝胶流变学性质的影响；考察甘草酸凝胶对橙皮苷的增溶效应及其对橙皮苷释放行为的影响。结果 在质量浓度5～60 mg/mL时，甘草酸凝胶的黏度、零剪切黏度、剪切稀化指数、剪切应力和黏弹性与甘草酸质量浓度间存在较高的相关性，甘草酸质量浓度的改变亦影响凝胶向溶胶转换时的模量的大小与应变值。此外，甘草酸凝胶的流变学性质还受到体系pH值、Na⁺质量浓度、Ca²⁺质量浓度的影响；橙皮苷在室温下的平衡溶解度为（21.47±1.10）μg/mL，橙皮苷-甘草酸凝胶中橙皮苷质量浓度为（126.95±2.83）μg/mL，甘草酸凝胶能够增大橙皮苷溶解度，提高其体外释放率，并对橙皮苷溶液发挥缓释作用。结论 基于不同制备条件下甘草酸凝胶流变学性质的可调节性及其对疏水性药物优异的增溶效果，甘草酸凝胶有望作为药物载体用于外用制剂及新型递药系统的开发。

Objective To investigate the rheological properties of glycyrrhizic acid gel and its solubilization effect on the hydrophobic drug hesperidin. Methods The rotational rheometer was used to carry out the strain scanning experiment and steady flow experiment on the glycyrrhizic acid gel obtained under different preparation conditions. The effects of the concentration of glycyrrhizic acid, the pH of solvent, the type and concentration of metal ions on the rheological properties of glycyrrhizic acid gel were investigated; The solubilization effect of glycyrrhizic acid gel on hesperidin and its effect on hesperidin release behavior were investigated. Results In the concentration range of 5—60 mg/mL, the viscosity, zero shear viscosity, shear thinning index, shear stress and viscoelasticity of glycyrrhizic acid gel are highly correlated with the concentration of glycyrrhizic acid, and the change of the concentration of glycyrrhizic acid also affects the modulus and strain value when the gel converts to sol. In addition, the rheological properties of glycyrrhizic acid gel were also affected by pH, Na⁺ concentration and Ca²⁺ concentration of the system; The equilibrium solubility of hesperidin at room temperature is (21.47 ± 1.10) μg/mL, the concentration of hesperidin in hesperidin glycyrrhizic acid gel is (126.95 ± 2.83) μg/mL, glycyrrhizic acid gel can increase the solubility of hesperidin, improve its in vitro release rate, and play a sustained release role on hesperidin solution. Conclusion Based on the adjustability of the rheological properties of glycyrrhizic acid gel under different preparation conditions and its excellent solubilization effect on hydrophobic drugs, glycyrrhizic acid gel is expected to be used as a drug carrier in the development of external preparations and new drug delivery systems.

R283.6

国家自然科学基金资助项目（82274111）